65b77c975b
I was seeing internal pages grow to contain over 70,000 entries. Which makes reconciliation of child pages very expensive. Be more aggressive about splitting internal pages.
1059 lines
49 KiB
Python
1059 lines
49 KiB
Python
# This file is a python script that describes the WiredTiger API.
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class Method:
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def __init__(self, config):
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self.config = config
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class Config:
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def __init__(self, name, default, desc, subconfig=None, **flags):
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self.name = name
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self.default = default
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self.desc = desc
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self.subconfig = subconfig
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self.flags = flags
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def __cmp__(self, other):
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return cmp(self.name, other.name)
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# Metadata shared by all schema objects
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common_meta = [
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Config('app_metadata', '', r'''
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application-owned metadata for this object'''),
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Config('collator', 'none', r'''
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configure custom collation for keys. Permitted values are \c "none"
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or a custom collator name created with WT_CONNECTION::add_collator'''),
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Config('columns', '', r'''
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list of the column names. Comma-separated list of the form
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<code>(column[,...])</code>. For tables, the number of entries
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must match the total number of values in \c key_format and \c
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value_format. For colgroups and indices, all column names must
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appear in the list of columns for the table''',
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type='list'),
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]
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source_meta = [
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Config('source', '', r'''
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set a custom data source URI for a column group, index or simple
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table. By default, the data source URI is derived from the \c
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type and the column group or index name. Applications can
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create tables from existing data sources by supplying a \c
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source configuration''', undoc=True),
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Config('type', 'file', r'''
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set the type of data source used to store a column group, index
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or simple table. By default, a \c "file:" URI is derived from
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the object name. The \c type configuration can be used to
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switch to a different data source, such as LSM or an extension
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configured by the application'''),
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]
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format_meta = common_meta + [
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Config('key_format', 'u', r'''
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the format of the data packed into key items. See @ref
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schema_format_types for details. By default, the key_format is
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\c 'u' and applications use WT_ITEM structures to manipulate
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raw byte arrays. By default, records are stored in row-store
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files: keys of type \c 'r' are record numbers and records
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referenced by record number are stored in column-store files''',
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type='format', func='__wt_struct_confchk'),
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Config('value_format', 'u', r'''
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the format of the data packed into value items. See @ref
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schema_format_types for details. By default, the value_format
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is \c 'u' and applications use a WT_ITEM structure to
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manipulate raw byte arrays. Value items of type 't' are
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bitfields, and when configured with record number type keys,
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will be stored using a fixed-length store''',
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type='format', func='__wt_struct_confchk'),
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]
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lsm_config = [
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Config('lsm', '', r'''
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options only relevant for LSM data sources''',
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type='category', subconfig=[
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Config('auto_throttle', 'true', r'''
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Throttle inserts into LSM trees if flushing to disk isn't
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keeping up''',
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type='boolean'),
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Config('bloom', 'true', r'''
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create bloom filters on LSM tree chunks as they are merged''',
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type='boolean'),
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Config('bloom_config', '', r'''
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config string used when creating Bloom filter files, passed
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to WT_SESSION::create'''),
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Config('bloom_bit_count', '16', r'''
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the number of bits used per item for LSM bloom filters''',
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min='2', max='1000'),
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Config('bloom_hash_count', '8', r'''
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the number of hash values per item used for LSM bloom
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filters''',
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min='2', max='100'),
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Config('bloom_oldest', 'false', r'''
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create a bloom filter on the oldest LSM tree chunk. Only
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supported if bloom filters are enabled''',
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type='boolean'),
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Config('chunk_count_limit', '0', r'''
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the maximum number of chunks to allow in an LSM tree. This
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option automatically times out old data. As new chunks are
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added old chunks will be removed. Enabling this option
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disables LSM background merges''',
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type='int'),
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Config('chunk_max', '5GB', r'''
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the maximum size a single chunk can be. Chunks larger than this
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size are not considered for further merges. This is a soft
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limit, and chunks larger than this value can be created. Must
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be larger than chunk_size''',
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min='100MB', max='10TB'),
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Config('chunk_size', '10MB', r'''
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the maximum size of the in-memory chunk of an LSM tree. This
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limit is soft - it is possible for chunks to be temporarily
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larger than this value. This overrides the \c memory_page_max
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setting''',
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min='512K', max='500MB'),
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Config('merge_max', '15', r'''
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the maximum number of chunks to include in a merge operation''',
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min='2', max='100'),
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Config('merge_min', '0', r'''
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the minimum number of chunks to include in a merge operation. If
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set to 0 or 1 half the value of merge_max is used''',
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max='100'),
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]),
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]
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# Per-file configuration
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file_config = format_meta + [
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Config('block_allocation', 'best', r'''
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configure block allocation. Permitted values are \c "first" or
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\c "best"; the \c "first" configuration uses a first-available
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algorithm during block allocation, the \c "best" configuration
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uses a best-fit algorithm''',
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choices=['first', 'best',]),
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Config('allocation_size', '4KB', r'''
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the file unit allocation size, in bytes, must a power-of-two;
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smaller values decrease the file space required by overflow
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items, and the default value of 4KB is a good choice absent
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requirements from the operating system or storage device''',
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min='512B', max='128MB'),
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Config('block_compressor', 'none', r'''
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configure a compressor for file blocks. Permitted values are \c "none"
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or custom compression engine name created with
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WT_CONNECTION::add_compressor. If WiredTiger has builtin support for
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\c "bzip2", \c "snappy", \c "lz4" or \c "zlib" compression, these names
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are also available. See @ref compression for more information'''),
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Config('cache_resident', 'false', r'''
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do not ever evict the object's pages from cache. Not compatible with
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LSM tables; see @ref tuning_cache_resident for more information''',
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type='boolean'),
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Config('checksum', 'uncompressed', r'''
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configure block checksums; permitted values are <code>on</code>
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(checksum all blocks), <code>off</code> (checksum no blocks) and
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<code>uncompresssed</code> (checksum only blocks which are not
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compressed for any reason). The \c uncompressed setting is for
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applications which can rely on decompression to fail if a block
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has been corrupted''',
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choices=['on', 'off', 'uncompressed']),
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Config('dictionary', '0', r'''
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the maximum number of unique values remembered in the Btree
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row-store leaf page value dictionary; see
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@ref file_formats_compression for more information''',
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min='0'),
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Config('encryption', '', r'''
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configure an encryptor for file blocks. When a table is created,
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its encryptor is not implicitly used for any related indices
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or column groups''',
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type='category', subconfig=[
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Config('name', 'none', r'''
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Permitted values are \c "none"
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or custom encryption engine name created with
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WT_CONNECTION::add_encryptor.
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See @ref encryption for more information'''),
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Config('keyid', '', r'''
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An identifier that identifies a unique instance of the encryptor.
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It is stored in clear text, and thus is available when
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the wiredtiger database is reopened. On the first use
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of a (name, keyid) combination, the WT_ENCRYPTOR::customize
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function is called with the keyid as an argument.'''),
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]),
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Config('format', 'btree', r'''
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the file format''',
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choices=['btree']),
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Config('huffman_key', 'none', r'''
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configure Huffman encoding for keys. Permitted values are
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\c "none", \c "english", \c "utf8<file>" or \c "utf16<file>".
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See @ref huffman for more information'''),
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Config('huffman_value', 'none', r'''
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configure Huffman encoding for values. Permitted values are
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\c "none", \c "english", \c "utf8<file>" or \c "utf16<file>".
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See @ref huffman for more information'''),
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Config('internal_key_truncate', 'true', r'''
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configure internal key truncation, discarding unnecessary
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trailing bytes on internal keys (ignored for custom
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collators)''',
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type='boolean'),
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Config('internal_page_max', '4KB', r'''
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the maximum page size for internal nodes, in bytes; the size
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must be a multiple of the allocation size and is significant
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for applications wanting to avoid excessive L2 cache misses
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while searching the tree. The page maximum is the bytes of
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uncompressed data, that is, the limit is applied before any
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block compression is done''',
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min='512B', max='512MB'),
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Config('internal_item_max', '0', r'''
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historic term for internal_key_max''',
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min=0, undoc=True),
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Config('internal_key_max', '0', r'''
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the largest key stored in an internal node, in bytes. If set, keys
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larger than the specified size are stored as overflow items (which
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may require additional I/O to access). The default and the maximum
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allowed value are both one-tenth the size of a newly split internal
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page''',
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min='0'),
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Config('key_gap', '10', r'''
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the maximum gap between instantiated keys in a Btree leaf page,
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constraining the number of keys processed to instantiate a
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random Btree leaf page key''',
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min='0', undoc=True),
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Config('leaf_key_max', '0', r'''
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the largest key stored in a leaf node, in bytes. If set, keys
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larger than the specified size are stored as overflow items (which
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may require additional I/O to access). The default value is
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one-tenth the size of a newly split leaf page''',
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min='0'),
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Config('leaf_page_max', '32KB', r'''
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the maximum page size for leaf nodes, in bytes; the size must
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be a multiple of the allocation size, and is significant for
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applications wanting to maximize sequential data transfer from
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a storage device. The page maximum is the bytes of uncompressed
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data, that is, the limit is applied before any block compression
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is done''',
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min='512B', max='512MB'),
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Config('leaf_value_max', '0', r'''
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the largest value stored in a leaf node, in bytes. If set, values
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larger than the specified size are stored as overflow items (which
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may require additional I/O to access). If the size is larger than
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the maximum leaf page size, the page size is temporarily ignored
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when large values are written. The default is one-half the size of
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a newly split leaf page''',
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min='0'),
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Config('leaf_item_max', '0', r'''
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historic term for leaf_key_max and leaf_value_max''',
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min=0, undoc=True),
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Config('log', '', r'''
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the transaction log configuration for this object. Only valid if
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log is enabled in ::wiredtiger_open.''',
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type='category', subconfig=[
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Config('enabled', 'true', r'''
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if false, this object has checkpoint-level durability.''',
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type='boolean'),
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]),
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Config('memory_page_max', '5MB', r'''
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the maximum size a page can grow to in memory before being
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reconciled to disk. The specified size will be adjusted to a lower
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bound of <code>50 * leaf_page_max</code>, and an upper bound of
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<code>cache_size / 2</code>. This limit is soft - it is possible
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for pages to be temporarily larger than this value. This setting
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is ignored for LSM trees, see \c chunk_size''',
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min='512B', max='10TB'),
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Config('os_cache_max', '0', r'''
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maximum system buffer cache usage, in bytes. If non-zero, evict
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object blocks from the system buffer cache after that many bytes
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from this object are read or written into the buffer cache''',
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min=0),
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Config('os_cache_dirty_max', '0', r'''
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maximum dirty system buffer cache usage, in bytes. If non-zero,
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schedule writes for dirty blocks belonging to this object in the
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system buffer cache after that many bytes from this object are
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written into the buffer cache''',
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min=0),
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Config('prefix_compression', 'false', r'''
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configure prefix compression on row-store leaf pages''',
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type='boolean'),
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Config('prefix_compression_min', '4', r'''
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minimum gain before prefix compression will be used on row-store
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leaf pages''',
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min=0),
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Config('split_deepen_min_child', '0', r'''
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minimum entries in a page to consider deepening the tree. Once
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there are more than this many entries pages will be immediately
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considered for splitting''',
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type='int', undoc=True),
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Config('split_deepen_per_child', '0', r'''
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entries allocated per child when deepening the tree''',
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type='int', undoc=True),
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Config('split_pct', '75', r'''
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the Btree page split size as a percentage of the maximum Btree
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page size, that is, when a Btree page is split, it will be
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split into smaller pages, where each page is the specified
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percentage of the maximum Btree page size''',
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min='25', max='100'),
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]
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# File metadata, including both configurable and non-configurable (internal)
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file_meta = file_config + [
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Config('checkpoint', '', r'''
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the file checkpoint entries'''),
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Config('checkpoint_lsn', '', r'''
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LSN of the last checkpoint'''),
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Config('id', '', r'''
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the file's ID number'''),
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Config('version', '(major=0,minor=0)', r'''
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the file version'''),
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]
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table_only_config = [
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Config('colgroups', '', r'''
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comma-separated list of names of column groups. Each column
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group is stored separately, keyed by the primary key of the
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table. If no column groups are specified, all columns are
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stored together in a single file. All value columns in the
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table must appear in at least one column group. Each column
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group must be created with a separate call to
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WT_SESSION::create''', type='list'),
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]
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index_only_config = [
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Config('extractor', 'none', r'''
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configure custom extractor for indices. Permitted values are
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\c "none" or an extractor name created with
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WT_CONNECTION::add_extractor'''),
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Config('immutable', 'false', r'''
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configure the index to be immutable - that is an index is not changed
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by any update to a record in the table''', type='boolean'),
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]
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colgroup_meta = common_meta + source_meta
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index_meta = format_meta + source_meta + index_only_config + [
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Config('index_key_columns', '', r'''
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number of public key columns''', type='int', undoc=True),
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]
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table_meta = format_meta + table_only_config
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# Connection runtime config, shared by conn.reconfigure and wiredtiger_open
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connection_runtime_config = [
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Config('async', '', r'''
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asynchronous operations configuration options''',
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type='category', subconfig=[
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Config('enabled', 'false', r'''
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enable asynchronous operation''',
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type='boolean'),
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Config('ops_max', '1024', r'''
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maximum number of expected simultaneous asynchronous
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operations''', min='1', max='4096'),
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Config('threads', '2', r'''
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the number of worker threads to service asynchronous requests.
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Each worker thread uses a session from the configured
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session_max.''',
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min='1', max='20'), # !!! Must match WT_ASYNC_MAX_WORKERS
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]),
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Config('cache_size', '100MB', r'''
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maximum heap memory to allocate for the cache. A database should
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configure either \c cache_size or \c shared_cache but not both''',
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min='1MB', max='10TB'),
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Config('cache_overhead', '8', r'''
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assume the heap allocator overhead is the specified percentage, and
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adjust the cache usage by that amount (for example, if there is 10GB
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of data in cache, a percentage of 10 means WiredTiger treats this as
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11GB). This value is configurable because different heap allocators
|
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have different overhead and different workloads will have different
|
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heap allocation sizes and patterns, therefore applications may need to
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adjust this value based on allocator choice and behavior in measured
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workloads''',
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min='0', max='30'),
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Config('checkpoint', '', r'''
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periodically checkpoint the database. Enabling the checkpoint server
|
|
uses a session from the configured session_max''',
|
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type='category', subconfig=[
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Config('name', '"WiredTigerCheckpoint"', r'''
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the checkpoint name'''),
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Config('log_size', '0', r'''
|
|
wait for this amount of log record bytes to be written to
|
|
the log between each checkpoint. A database can configure
|
|
both log_size and wait to set an upper bound for checkpoints;
|
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setting this value above 0 configures periodic checkpoints''',
|
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min='0', max='2GB'),
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Config('wait', '0', r'''
|
|
seconds to wait between each checkpoint; setting this value
|
|
above 0 configures periodic checkpoints''',
|
|
min='0', max='100000'),
|
|
]),
|
|
Config('error_prefix', '', r'''
|
|
prefix string for error messages'''),
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Config('eviction_dirty_target', '80', r'''
|
|
continue evicting until the cache has less dirty memory than the
|
|
value, as a percentage of the total cache size. Dirty pages will
|
|
only be evicted if the cache is full enough to trigger eviction''',
|
|
min=5, max=99),
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Config('eviction_dirty_trigger', '95', r'''
|
|
trigger eviction when the cache is using this much memory for dirty
|
|
content, as a percentage of the total cache size. This setting only
|
|
alters behavior if it is lower than eviction_trigger''',
|
|
min=5, max=99),
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|
Config('eviction_target', '80', r'''
|
|
continue evicting until the cache has less total memory than the
|
|
value, as a percentage of the total cache size. Must be less than
|
|
\c eviction_trigger''',
|
|
min=10, max=99),
|
|
Config('eviction_trigger', '95', r'''
|
|
trigger eviction when the cache is using this much memory, as a
|
|
percentage of the total cache size''', min=10, max=99),
|
|
Config('file_manager', '', r'''
|
|
control how file handles are managed''',
|
|
type='category', subconfig=[
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|
Config('close_handle_minimum', '250', r'''
|
|
number of handles open before the file manager will look for handles
|
|
to close''', min=0),
|
|
Config('close_idle_time', '30', r'''
|
|
amount of time in seconds a file handle needs to be idle
|
|
before attempting to close it. A setting of 0 means that idle
|
|
handles are not closed''', min=0, max=100000),
|
|
Config('close_scan_interval', '10', r'''
|
|
interval in seconds at which to check for files that are
|
|
inactive and close them''', min=1, max=100000),
|
|
]),
|
|
Config('lsm_manager', '', r'''
|
|
configure database wide options for LSM tree management. The LSM
|
|
manager is started automatically the first time an LSM tree is opened.
|
|
The LSM manager uses a session from the configured session_max.''',
|
|
type='category', subconfig=[
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Config('worker_thread_max', '4', r'''
|
|
Configure a set of threads to manage merging LSM trees in
|
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the database. Each worker thread uses a session handle from
|
|
the configured session_max''',
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min='3', # !!! Must match WT_LSM_MIN_WORKERS
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max='20'), # !!! Must match WT_LSM_MAX_WORKERS
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Config('merge', 'true', r'''
|
|
merge LSM chunks where possible''',
|
|
type='boolean')
|
|
]),
|
|
Config('lsm_merge', 'true', r'''
|
|
merge LSM chunks where possible (deprecated)''',
|
|
type='boolean', undoc=True),
|
|
Config('eviction', '', r'''
|
|
eviction configuration options.''',
|
|
type='category', subconfig=[
|
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Config('threads_max', '1', r'''
|
|
maximum number of threads WiredTiger will start to help evict
|
|
pages from cache. The number of threads started will vary
|
|
depending on the current eviction load. Each eviction worker
|
|
thread uses a session from the configured session_max''',
|
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min=1, max=20),
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Config('threads_min', '1', r'''
|
|
minimum number of threads WiredTiger will start to help evict
|
|
pages from cache. The number of threads currently running will
|
|
vary depending on the current eviction load''',
|
|
min=1, max=20),
|
|
]),
|
|
Config('shared_cache', '', r'''
|
|
shared cache configuration options. A database should configure
|
|
either a cache_size or a shared_cache not both. Enabling a
|
|
shared cache uses a session from the configured session_max''',
|
|
type='category', subconfig=[
|
|
Config('chunk', '10MB', r'''
|
|
the granularity that a shared cache is redistributed''',
|
|
min='1MB', max='10TB'),
|
|
Config('name', 'none', r'''
|
|
the name of a cache that is shared between databases or
|
|
\c "none" when no shared cache is configured'''),
|
|
Config('quota', '0', r'''
|
|
maximum size of cache this database can be allocated from the
|
|
shared cache. Defaults to the entire shared cache size''',
|
|
type='int'),
|
|
Config('reserve', '0', r'''
|
|
amount of cache this database is guaranteed to have
|
|
available from the shared cache. This setting is per
|
|
database. Defaults to the chunk size''', type='int'),
|
|
Config('size', '500MB', r'''
|
|
maximum memory to allocate for the shared cache. Setting
|
|
this will update the value if one is already set''',
|
|
min='1MB', max='10TB')
|
|
]),
|
|
Config('statistics', 'none', r'''
|
|
Maintain database statistics, which may impact performance.
|
|
Choosing "all" maintains all statistics regardless of cost,
|
|
"fast" maintains a subset of statistics that are relatively
|
|
inexpensive, "none" turns off all statistics. The "clear"
|
|
configuration resets statistics after they are gathered,
|
|
where appropriate (for example, a cache size statistic is
|
|
not cleared, while the count of cursor insert operations will
|
|
be cleared). When "clear" is configured for the database,
|
|
gathered statistics are reset each time a statistics cursor
|
|
is used to gather statistics, as well as each time statistics
|
|
are logged using the \c statistics_log configuration. See
|
|
@ref statistics for more information''',
|
|
type='list', choices=['all', 'fast', 'none', 'clear']),
|
|
Config('statistics_log', '', r'''
|
|
log any statistics the database is configured to maintain,
|
|
to a file. See @ref statistics for more information. Enabling
|
|
the statistics log server uses a session from the configured
|
|
session_max''',
|
|
type='category', subconfig=[
|
|
Config('on_close', 'false', r'''log statistics on database close''',
|
|
type='boolean'),
|
|
Config('path', '"WiredTigerStat.%d.%H"', r'''
|
|
the pathname to a file into which the log records are written,
|
|
may contain ISO C standard strftime conversion specifications.
|
|
If the value is not an absolute path name, the file is created
|
|
relative to the database home'''),
|
|
Config('sources', '', r'''
|
|
if non-empty, include statistics for the list of data source
|
|
URIs, if they are open at the time of the statistics logging.
|
|
The list may include URIs matching a single data source
|
|
("table:mytable"), or a URI matching all data sources of a
|
|
particular type ("table:")''',
|
|
type='list'),
|
|
Config('timestamp', '"%b %d %H:%M:%S"', r'''
|
|
a timestamp prepended to each log record, may contain strftime
|
|
conversion specifications'''),
|
|
Config('wait', '0', r'''
|
|
seconds to wait between each write of the log records; setting
|
|
this value above 0 configures statistics logging''',
|
|
min='0', max='100000'),
|
|
]),
|
|
Config('verbose', '', r'''
|
|
enable messages for various events. Only available if WiredTiger
|
|
is configured with --enable-verbose. Options are given as a
|
|
list, such as <code>"verbose=[evictserver,read]"</code>''',
|
|
type='list', choices=[
|
|
'api',
|
|
'block',
|
|
'checkpoint',
|
|
'compact',
|
|
'evict',
|
|
'evictserver',
|
|
'fileops',
|
|
'log',
|
|
'lsm',
|
|
'lsm_manager',
|
|
'metadata',
|
|
'mutex',
|
|
'overflow',
|
|
'read',
|
|
'reconcile',
|
|
'recovery',
|
|
'salvage',
|
|
'shared_cache',
|
|
'split',
|
|
'temporary',
|
|
'transaction',
|
|
'verify',
|
|
'version',
|
|
'write']),
|
|
]
|
|
|
|
session_config = [
|
|
Config('isolation', 'read-committed', r'''
|
|
the default isolation level for operations in this session''',
|
|
choices=['read-uncommitted', 'read-committed', 'snapshot']),
|
|
]
|
|
|
|
common_wiredtiger_open = [
|
|
Config('buffer_alignment', '-1', r'''
|
|
in-memory alignment (in bytes) for buffers used for I/O. The
|
|
default value of -1 indicates a platform-specific alignment value
|
|
should be used (4KB on Linux systems when direct I/O is configured,
|
|
zero elsewhere)''',
|
|
min='-1', max='1MB'),
|
|
Config('checkpoint_sync', 'true', r'''
|
|
flush files to stable storage when closing or writing
|
|
checkpoints''',
|
|
type='boolean'),
|
|
Config('direct_io', '', r'''
|
|
Use \c O_DIRECT to access files. Options are given as a list,
|
|
such as <code>"direct_io=[data]"</code>. Configuring
|
|
\c direct_io requires care, see @ref
|
|
tuning_system_buffer_cache_direct_io for important warnings.
|
|
Including \c "data" will cause WiredTiger data files to use
|
|
\c O_DIRECT, including \c "log" will cause WiredTiger log files
|
|
to use \c O_DIRECT, and including \c "checkpoint" will cause
|
|
WiredTiger data files opened at a checkpoint (i.e: read only) to
|
|
use \c O_DIRECT''',
|
|
type='list', choices=['checkpoint', 'data', 'log']),
|
|
Config('encryption', '', r'''
|
|
configure an encryptor for system wide metadata and logs.
|
|
If a system wide encryptor is set, it is also used for
|
|
encrypting data files and tables, unless encryption configuration
|
|
is explicitly set for them when they are created with
|
|
WT_SESSION::create''',
|
|
type='category', subconfig=[
|
|
Config('name', 'none', r'''
|
|
Permitted values are \c "none"
|
|
or custom encryption engine name created with
|
|
WT_CONNECTION::add_encryptor.
|
|
See @ref encryption for more information'''),
|
|
Config('keyid', '', r'''
|
|
An identifier that identifies a unique instance of the encryptor.
|
|
It is stored in clear text, and thus is available when
|
|
the wiredtiger database is reopened. On the first use
|
|
of a (name, keyid) combination, the WT_ENCRYPTOR::customize
|
|
function is called with the keyid as an argument.'''),
|
|
Config('secretkey', '', r'''
|
|
A string that is passed to the WT_ENCRYPTOR::customize function.
|
|
It is never stored in clear text, so must be given to any
|
|
subsequent ::wiredtiger_open calls to reopen the database.
|
|
It must also be provided to any "wt" commands used with
|
|
this database.'''),
|
|
]),
|
|
Config('extensions', '', r'''
|
|
list of shared library extensions to load (using dlopen).
|
|
Any values specified to an library extension are passed to
|
|
WT_CONNECTION::load_extension as the \c config parameter
|
|
(for example,
|
|
<code>extensions=(/path/ext.so={entry=my_entry})</code>)''',
|
|
type='list'),
|
|
Config('file_extend', '', r'''
|
|
file extension configuration. If set, extend files of the set
|
|
type in allocations of the set size, instead of a block at a
|
|
time as each new block is written. For example,
|
|
<code>file_extend=(data=16MB)</code>''',
|
|
type='list', choices=['data', 'log']),
|
|
Config('hazard_max', '1000', r'''
|
|
maximum number of simultaneous hazard pointers per session
|
|
handle''',
|
|
min='15'),
|
|
Config('log', '', r'''
|
|
enable logging. Enabling logging uses three sessions from the
|
|
configured session_max''',
|
|
type='category', subconfig=[
|
|
Config('archive', 'true', r'''
|
|
automatically archive unneeded log files''',
|
|
type='boolean'),
|
|
Config('compressor', 'none', r'''
|
|
configure a compressor for log records. Permitted values are
|
|
\c "none" or custom compression engine name created with
|
|
WT_CONNECTION::add_compressor. If WiredTiger has builtin support
|
|
for \c "bzip2", \c "snappy", \c "lz4" or \c "zlib" compression,
|
|
these names are also available. See @ref compression for more
|
|
information'''),
|
|
Config('enabled', 'false', r'''
|
|
enable logging subsystem''',
|
|
type='boolean'),
|
|
Config('file_max', '100MB', r'''
|
|
the maximum size of log files''',
|
|
min='100KB', max='2GB'),
|
|
Config('path', '', r'''
|
|
the path to a directory into which the log files are written.
|
|
If the value is not an absolute path name, the files are created
|
|
relative to the database home'''),
|
|
Config('prealloc', 'true', r'''
|
|
pre-allocate log files.''',
|
|
type='boolean'),
|
|
Config('recover', 'on', r'''
|
|
run recovery or error if recovery needs to run after an
|
|
unclean shutdown.''',
|
|
choices=['error','on']),
|
|
]),
|
|
Config('mmap', 'true', r'''
|
|
Use memory mapping to access files when possible''',
|
|
type='boolean'),
|
|
Config('multiprocess', 'false', r'''
|
|
permit sharing between processes (will automatically start an
|
|
RPC server for primary processes and use RPC for secondary
|
|
processes). <b>Not yet supported in WiredTiger</b>''',
|
|
type='boolean'),
|
|
Config('session_max', '100', r'''
|
|
maximum expected number of sessions (including server
|
|
threads)''',
|
|
min='1'),
|
|
Config('session_scratch_max', '2MB', r'''
|
|
maximum memory to cache in each session''',
|
|
type='int', undoc=True),
|
|
Config('transaction_sync', '', r'''
|
|
how to sync log records when the transaction commits''',
|
|
type='category', subconfig=[
|
|
Config('enabled', 'false', r'''
|
|
whether to sync the log on every commit by default, can be
|
|
overridden by the \c sync setting to
|
|
WT_SESSION::commit_transaction''',
|
|
type='boolean'),
|
|
Config('method', 'fsync', r'''
|
|
the method used to ensure log records are stable on disk, see
|
|
@ref tune_durability for more information''',
|
|
choices=['dsync', 'fsync', 'none']),
|
|
]),
|
|
]
|
|
|
|
cursor_runtime_config = [
|
|
Config('append', 'false', r'''
|
|
append the value as a new record, creating a new record
|
|
number key; valid only for cursors with record number keys''',
|
|
type='boolean'),
|
|
Config('overwrite', 'true', r'''
|
|
configures whether the cursor's insert, update and remove
|
|
methods check the existing state of the record. If \c overwrite
|
|
is \c false, WT_CURSOR::insert fails with ::WT_DUPLICATE_KEY
|
|
if the record exists, WT_CURSOR::update and WT_CURSOR::remove
|
|
fail with ::WT_NOTFOUND if the record does not exist''',
|
|
type='boolean'),
|
|
]
|
|
|
|
methods = {
|
|
'file.meta' : Method(file_meta),
|
|
|
|
'colgroup.meta' : Method(colgroup_meta),
|
|
|
|
'index.meta' : Method(index_meta),
|
|
|
|
'table.meta' : Method(table_meta),
|
|
|
|
'WT_CURSOR.close' : Method([]),
|
|
|
|
'WT_CURSOR.reconfigure' : Method(cursor_runtime_config),
|
|
|
|
'WT_SESSION.close' : Method([]),
|
|
|
|
'WT_SESSION.compact' : Method([
|
|
Config('timeout', '1200', r'''
|
|
maximum amount of time to allow for compact in seconds. The
|
|
actual amount of time spent in compact may exceed the configured
|
|
value. A value of zero disables the timeout''',
|
|
type='int'),
|
|
]),
|
|
|
|
'WT_SESSION.create' : Method(file_config + lsm_config + source_meta +
|
|
index_only_config + table_only_config + [
|
|
Config('exclusive', 'false', r'''
|
|
fail if the object exists. When false (the default), if the
|
|
object exists, check that its settings match the specified
|
|
configuration''',
|
|
type='boolean'),
|
|
]),
|
|
|
|
'WT_SESSION.drop' : Method([
|
|
Config('force', 'false', r'''
|
|
return success if the object does not exist''',
|
|
type='boolean'),
|
|
Config('remove_files', 'true', r'''
|
|
should the underlying files be removed?''',
|
|
type='boolean'),
|
|
]),
|
|
|
|
'WT_SESSION.log_flush' : Method([
|
|
Config('sync', 'on', r'''
|
|
forcibly flush the log and wait for it to achieve the synchronization
|
|
level specified. The \c background setting initiates a background
|
|
synchronization intended to be used with a later call to
|
|
WT_SESSION::transaction_sync. The \c off setting forces any
|
|
buffered log records to be written to the file system. The
|
|
\c on setting forces log records to be written to the storage device''',
|
|
choices=['background', 'off', 'on']),
|
|
]),
|
|
|
|
'WT_SESSION.log_printf' : Method([]),
|
|
|
|
'WT_SESSION.open_cursor' : Method(cursor_runtime_config + [
|
|
Config('bulk', 'false', r'''
|
|
configure the cursor for bulk-loading, a fast, initial load
|
|
path (see @ref tune_bulk_load for more information). Bulk-load
|
|
may only be used for newly created objects and cursors
|
|
configured for bulk-load only support the WT_CURSOR::insert
|
|
and WT_CURSOR::close methods. When bulk-loading row-store
|
|
objects, keys must be loaded in sorted order. The value is
|
|
usually a true/false flag; when bulk-loading fixed-length
|
|
column store objects, the special value \c bitmap allows
|
|
chunks of a memory resident bitmap to be loaded directly into
|
|
a file by passing a \c WT_ITEM to WT_CURSOR::set_value where
|
|
the \c size field indicates the number of records in the
|
|
bitmap (as specified by the object's \c value_format
|
|
configuration). Bulk-loaded bitmap values must end on a byte
|
|
boundary relative to the bit count (except for the last set
|
|
of values loaded)'''),
|
|
Config('checkpoint', '', r'''
|
|
the name of a checkpoint to open (the reserved name
|
|
"WiredTigerCheckpoint" opens the most recent internal
|
|
checkpoint taken for the object). The cursor does not
|
|
support data modification'''),
|
|
Config('dump', '', r'''
|
|
configure the cursor for dump format inputs and outputs: "hex"
|
|
selects a simple hexadecimal format, "json" selects a JSON format
|
|
with each record formatted as fields named by column names if
|
|
available, and "print" selects a format where only non-printing
|
|
characters are hexadecimal encoded. These formats are compatible
|
|
with the @ref util_dump and @ref util_load commands''',
|
|
choices=['hex', 'json', 'print']),
|
|
Config('next_random', 'false', r'''
|
|
configure the cursor to return a pseudo-random record from
|
|
the object; valid only for row-store cursors. Cursors
|
|
configured with \c next_random=true only support the
|
|
WT_CURSOR::next and WT_CURSOR::close methods. See @ref
|
|
cursor_random for details''',
|
|
type='boolean'),
|
|
Config('raw', 'false', r'''
|
|
ignore the encodings for the key and value, manage data as if
|
|
the formats were \c "u". See @ref cursor_raw for details''',
|
|
type='boolean'),
|
|
Config('readonly', 'false', r'''
|
|
only query operations are supported by this cursor. An error is
|
|
returned if a modification is attempted using the cursor. The
|
|
default is false for all cursor types except for log and metadata
|
|
cursors''',
|
|
type='boolean'),
|
|
Config('skip_sort_check', 'false', r'''
|
|
skip the check of the sort order of each bulk-loaded key''',
|
|
type='boolean', undoc=True),
|
|
Config('statistics', '', r'''
|
|
Specify the statistics to be gathered. Choosing "all" gathers
|
|
statistics regardless of cost and may include traversing on-disk files;
|
|
"fast" gathers a subset of relatively inexpensive statistics. The
|
|
selection must agree with the database \c statistics configuration
|
|
specified to ::wiredtiger_open or WT_CONNECTION::reconfigure. For
|
|
example, "all" or "fast" can be configured when the database is
|
|
configured with "all", but the cursor open will fail if "all" is
|
|
specified when the database is configured with "fast", and the cursor
|
|
open will fail in all cases when the database is configured with
|
|
"none". If "size" is configured, only the underlying size of the
|
|
object on disk is filled in and the object is not opened. If \c
|
|
statistics is not configured, the default configuration is the database
|
|
configuration. The "clear" configuration resets statistics after
|
|
gathering them, where appropriate (for example, a cache size statistic
|
|
is not cleared, while the count of cursor insert operations will be
|
|
cleared). See @ref statistics for more information''',
|
|
type='list', choices=['all', 'fast', 'clear', 'size']),
|
|
Config('target', '', r'''
|
|
if non-empty, backup the list of objects; valid only for a
|
|
backup data source''',
|
|
type='list'),
|
|
]),
|
|
|
|
'WT_SESSION.rename' : Method([]),
|
|
'WT_SESSION.reset' : Method([]),
|
|
'WT_SESSION.salvage' : Method([
|
|
Config('force', 'false', r'''
|
|
force salvage even of files that do not appear to be WiredTiger
|
|
files''',
|
|
type='boolean'),
|
|
]),
|
|
'WT_SESSION.strerror' : Method([]),
|
|
'WT_SESSION.transaction_sync' : Method([
|
|
Config('timeout_ms', '1200000', r'''
|
|
maximum amount of time to wait for background sync to complete in
|
|
milliseconds. A value of zero disables the timeout and returns
|
|
immediately.''',
|
|
type='int'),
|
|
]),
|
|
|
|
'WT_SESSION.truncate' : Method([]),
|
|
'WT_SESSION.upgrade' : Method([]),
|
|
'WT_SESSION.verify' : Method([
|
|
Config('dump_address', 'false', r'''
|
|
Display addresses and page types as pages are verified,
|
|
using the application's message handler, intended for debugging''',
|
|
type='boolean'),
|
|
Config('dump_blocks', 'false', r'''
|
|
Display the contents of on-disk blocks as they are verified,
|
|
using the application's message handler, intended for debugging''',
|
|
type='boolean'),
|
|
Config('dump_offsets', '', r'''
|
|
Display the contents of specific on-disk blocks,
|
|
using the application's message handler, intended for debugging''',
|
|
type='list'),
|
|
Config('dump_pages', 'false', r'''
|
|
Display the contents of in-memory pages as they are verified,
|
|
using the application's message handler, intended for debugging''',
|
|
type='boolean'),
|
|
Config('dump_shape', 'false', r'''
|
|
Display the shape of the tree after verification,
|
|
using the application's message handler, intended for debugging''',
|
|
type='boolean'),
|
|
Config('strict', 'false', r'''
|
|
Treat any verification problem as an error; by default, verify will
|
|
warn, but not fail, in the case of errors that won't affect future
|
|
behavior (for example, a leaked block)''',
|
|
type='boolean')
|
|
]),
|
|
|
|
'WT_SESSION.begin_transaction' : Method([
|
|
Config('isolation', '', r'''
|
|
the isolation level for this transaction; defaults to the
|
|
session's isolation level''',
|
|
choices=['read-uncommitted', 'read-committed', 'snapshot']),
|
|
Config('name', '', r'''
|
|
name of the transaction for tracing and debugging'''),
|
|
Config('priority', 0, r'''
|
|
priority of the transaction for resolving conflicts.
|
|
Transactions with higher values are less likely to abort''',
|
|
min='-100', max='100'),
|
|
Config('snapshot', '', r'''
|
|
use a named, in-memory snapshot, see
|
|
@ref transaction_named_snapshots'''),
|
|
Config('sync', '', r'''
|
|
whether to sync log records when the transaction commits,
|
|
inherited from ::wiredtiger_open \c transaction_sync''',
|
|
type='boolean'),
|
|
]),
|
|
|
|
'WT_SESSION.commit_transaction' : Method([
|
|
Config('sync', '', r'''
|
|
override whether to sync log records when the transaction commits,
|
|
inherited from ::wiredtiger_open \c transaction_sync.
|
|
The \c background setting initiates a background
|
|
synchronization intended to be used with a later call to
|
|
WT_SESSION::transaction_sync. The \c off setting does not
|
|
wait for record to be written or synchronized. The
|
|
\c on setting forces log records to be written to the storage device''',
|
|
choices=['background', 'off', 'on']),
|
|
]),
|
|
'WT_SESSION.rollback_transaction' : Method([]),
|
|
|
|
'WT_SESSION.checkpoint' : Method([
|
|
Config('drop', '', r'''
|
|
specify a list of checkpoints to drop.
|
|
The list may additionally contain one of the following keys:
|
|
\c "from=all" to drop all checkpoints,
|
|
\c "from=<checkpoint>" to drop all checkpoints after and
|
|
including the named checkpoint, or
|
|
\c "to=<checkpoint>" to drop all checkpoints before and
|
|
including the named checkpoint. Checkpoints cannot be
|
|
dropped while a hot backup is in progress or if open in
|
|
a cursor''', type='list'),
|
|
Config('force', 'false', r'''
|
|
by default, checkpoints may be skipped if the underlying object
|
|
has not been modified, this option forces the checkpoint''',
|
|
type='boolean'),
|
|
Config('name', '', r'''
|
|
if set, specify a name for the checkpoint (note that checkpoints
|
|
including LSM trees may not be named)'''),
|
|
Config('target', '', r'''
|
|
if non-empty, checkpoint the list of objects''', type='list'),
|
|
]),
|
|
|
|
'WT_SESSION.snapshot' : Method([
|
|
Config('drop', '', r'''
|
|
if non-empty, specifies which snapshots to drop. Where a group
|
|
of snapshots are being dropped, the order is based on snapshot
|
|
creation order not alphanumeric name order''',
|
|
type='category', subconfig=[
|
|
Config('all', 'false', r'''
|
|
drop all named snapshots''', type='boolean'),
|
|
Config('before', '', r'''
|
|
drop all snapshots up to but not including the specified name'''),
|
|
Config('names', '', r'''
|
|
drop specific named snapshots''', type='list'),
|
|
Config('to', '', r'''
|
|
drop all snapshots up to and including the specified name.'''),
|
|
]),
|
|
Config('name', '', r'''specify a name for the snapshot'''),
|
|
]),
|
|
|
|
'WT_CONNECTION.add_collator' : Method([]),
|
|
'WT_CONNECTION.add_compressor' : Method([]),
|
|
'WT_CONNECTION.add_data_source' : Method([]),
|
|
'WT_CONNECTION.add_encryptor' : Method([]),
|
|
'WT_CONNECTION.add_extractor' : Method([]),
|
|
'WT_CONNECTION.async_new_op' : Method([
|
|
Config('append', 'false', r'''
|
|
append the value as a new record, creating a new record
|
|
number key; valid only for operations with record number keys''',
|
|
type='boolean'),
|
|
Config('overwrite', 'true', r'''
|
|
configures whether the cursor's insert, update and remove
|
|
methods check the existing state of the record. If \c overwrite
|
|
is \c false, WT_CURSOR::insert fails with ::WT_DUPLICATE_KEY
|
|
if the record exists, WT_CURSOR::update and WT_CURSOR::remove
|
|
fail with ::WT_NOTFOUND if the record does not exist''',
|
|
type='boolean'),
|
|
Config('raw', 'false', r'''
|
|
ignore the encodings for the key and value, manage data as if
|
|
the formats were \c "u". See @ref cursor_raw for details''',
|
|
type='boolean'),
|
|
Config('timeout', '1200', r'''
|
|
maximum amount of time to allow for compact in seconds. The
|
|
actual amount of time spent in compact may exceed the configured
|
|
value. A value of zero disables the timeout''',
|
|
type='int'),
|
|
]),
|
|
'WT_CONNECTION.close' : Method([
|
|
Config('leak_memory', 'false', r'''
|
|
don't free memory during close''',
|
|
type='boolean'),
|
|
]),
|
|
'WT_CONNECTION.reconfigure' : Method(connection_runtime_config),
|
|
|
|
'WT_CONNECTION.load_extension' : Method([
|
|
Config('config', '', r'''
|
|
configuration string passed to the entry point of the
|
|
extension as its WT_CONFIG_ARG argument'''),
|
|
Config('entry', 'wiredtiger_extension_init', r'''
|
|
the entry point of the extension, called to initialize the
|
|
extension when it is loaded. The signature of the function
|
|
must match ::wiredtiger_extension_init'''),
|
|
Config('terminate', 'wiredtiger_extension_terminate', r'''
|
|
an optional function in the extension that is called before
|
|
the extension is unloaded during WT_CONNECTION::close. The
|
|
signature of the function must match
|
|
::wiredtiger_extension_terminate'''),
|
|
]),
|
|
|
|
'WT_CONNECTION.open_session' : Method(session_config),
|
|
|
|
'WT_SESSION.reconfigure' : Method(session_config),
|
|
|
|
# There are 4 variants of the wiredtiger_open configurations.
|
|
# wiredtiger_open:
|
|
# Configuration values allowed in the application's configuration
|
|
# argument to the wiredtiger_open call.
|
|
# wiredtiger_open_basecfg:
|
|
# Configuration values allowed in the WiredTiger.basecfg file (remove
|
|
# creation-specific configuration strings and add a version string).
|
|
# wiredtiger_open_usercfg:
|
|
# Configuration values allowed in the WiredTiger.config file (remove
|
|
# creation-specific configuration strings).
|
|
# wiredtiger_open_all:
|
|
# All of the above configuration values combined
|
|
'wiredtiger_open' : Method(
|
|
connection_runtime_config +
|
|
common_wiredtiger_open + [
|
|
Config('config_base', 'true', r'''
|
|
write the base configuration file if creating the database. If
|
|
\c false in the config passed directly to ::wiredtiger_open, will
|
|
ignore any existing base configuration file in addition to not creating
|
|
one. See @ref config_base for more information''',
|
|
type='boolean'),
|
|
Config('create', 'false', r'''
|
|
create the database if it does not exist''',
|
|
type='boolean'),
|
|
Config('exclusive', 'false', r'''
|
|
fail if the database already exists, generally used with the
|
|
\c create option''',
|
|
type='boolean'),
|
|
Config('use_environment_priv', 'false', r'''
|
|
use the \c WIREDTIGER_CONFIG and \c WIREDTIGER_HOME environment
|
|
variables regardless of whether or not the process is running
|
|
with special privileges. See @ref home for more information''',
|
|
type='boolean'),
|
|
]),
|
|
'wiredtiger_open_basecfg' : Method(
|
|
connection_runtime_config +
|
|
common_wiredtiger_open + [
|
|
Config('version', '(major=0,minor=0)', r'''
|
|
the file version'''),
|
|
]),
|
|
'wiredtiger_open_usercfg' : Method(
|
|
connection_runtime_config +
|
|
common_wiredtiger_open
|
|
),
|
|
'wiredtiger_open_all' : Method(
|
|
connection_runtime_config +
|
|
common_wiredtiger_open + [
|
|
Config('config_base', 'true', r'''
|
|
write the base configuration file if creating the database. If
|
|
\c false in the config passed directly to ::wiredtiger_open, will
|
|
ignore any existing base configuration file in addition to not creating
|
|
one. See @ref config_base for more information''',
|
|
type='boolean'),
|
|
Config('create', 'false', r'''
|
|
create the database if it does not exist''',
|
|
type='boolean'),
|
|
Config('exclusive', 'false', r'''
|
|
fail if the database already exists, generally used with the
|
|
\c create option''',
|
|
type='boolean'),
|
|
Config('use_environment_priv', 'false', r'''
|
|
use the \c WIREDTIGER_CONFIG and \c WIREDTIGER_HOME environment
|
|
variables regardless of whether or not the process is running
|
|
with special privileges. See @ref home for more information''',
|
|
type='boolean'),
|
|
Config('version', '(major=0,minor=0)', r'''
|
|
the file version'''),
|
|
]),
|
|
}
|