MediaWiki master
|
RDBMS-based caching module. More...
Inherits Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Public Member Functions | |
__construct ( $params) | |
Create a new backend instance from parameters injected by ObjectCache::newFromParams() | |
createTables () | |
Create the shard tables on all databases. | |
deleteAll () | |
Delete content of shard tables in every server. | |
deleteObjectsExpiringBefore ( $timestamp, ?callable $progress=null, $limit=INF, ?string $tag=null) | |
Delete all objects expiring before a certain date. | |
doChangeTTLMulti (array $keys, $exptime, $flags=0) | |
doLock ( $key, $timeout=6, $exptime=6) | |
doUnlock ( $key) | |
expireAll () | |
Public Member Functions inherited from Wikimedia\ObjectCache\MediumSpecificBagOStuff | |
__construct (array $params=[]) | |
add ( $key, $value, $exptime=0, $flags=0) | |
Insert an item if it does not already exist. | |
changeTTL ( $key, $exptime=0, $flags=0) | |
Change the expiration on a key if it exists. | |
changeTTLMulti (array $keys, $exptime, $flags=0) | |
Change the expiration of multiple keys that exist. | |
delete ( $key, $flags=0) | |
Delete an item if it exists. | |
deleteMulti (array $keys, $flags=0) | |
Delete a batch of items. | |
get ( $key, $flags=0) | |
Get an item with the given key. | |
getMulti (array $keys, $flags=0) | |
Get an associative array containing the item for each of the keys that have items. | |
getQoS ( $flag) | |
getSegmentationSize () | |
getSegmentedValueMaxSize () | |
incrWithInit ( $key, $exptime, $step=1, $init=null, $flags=0) | |
Increase the value of the given key (no TTL change) if it exists or create it otherwise. | |
lock ( $key, $timeout=6, $exptime=6, $rclass='') | |
merge ( $key, callable $callback, $exptime=0, $attempts=10, $flags=0) | |
Merge changes into the existing cache value (possibly creating a new one) | |
set ( $key, $value, $exptime=0, $flags=0) | |
Set an item. | |
setMulti (array $valueByKey, $exptime=0, $flags=0) | |
Batch insertion/replace. | |
unlock ( $key) | |
Release an advisory lock on a key string. | |
Public Member Functions inherited from Wikimedia\ObjectCache\BagOStuff | |
clearLastError () | |
Clear the "last error" registry. | |
getCurrentTime () | |
getLastError ( $watchPoint=0) | |
Get the "last error" registry. | |
getLogger () | |
getScopedLock ( $key, $timeout=6, $exptime=30, $rclass='') | |
Get a lightweight exclusive self-unlocking lock. | |
getWithSetCallback ( $key, $exptime, $callback, $flags=0) | |
Get an item, regenerating and setting it if not found. | |
isKeyGlobal ( $key) | |
Check whether a cache key is in the global keyspace. | |
makeGlobalKey ( $keygroup,... $components) | |
Make a cache key from the given components, in the "global" keyspace. | |
makeKey ( $keygroup,... $components) | |
Make a cache key from the given components, in the default keyspace. | |
setLogger (LoggerInterface $logger) | |
setMockTime (&$time) | |
watchErrors () | |
Get a "watch point" token that can be used to get the "last error" to occur after now. | |
Protected Member Functions | |
doAdd ( $key, $value, $exptime=0, $flags=0) | |
Insert an item if it does not already exist. | |
doCas ( $casToken, $key, $value, $exptime=0, $flags=0) | |
Set an item if the current CAS token matches the provided CAS token. | |
doChangeTTL ( $key, $exptime, $flags) | |
doDelete ( $key, $flags=0) | |
Delete an item. | |
doDeleteMulti (array $keys, $flags=0) | |
doGet ( $key, $flags=0, &$casToken=null) | |
Get an item. | |
doGetMulti (array $keys, $flags=0) | |
Get an associative array containing the item for each of the keys that have items. | |
doIncrWithInit ( $key, $exptime, $step, $init, $flags) | |
doSet ( $key, $value, $exptime=0, $flags=0) | |
Set an item. | |
doSetMulti (array $data, $exptime=0, $flags=0) | |
makeKeyInternal ( $keyspace, $components) | |
Make a cache key for the given keyspace and components. | |
requireConvertGenericKey () | |
Whether ::proxyCall() must re-encode cache keys before calling read/write methods. | |
serialize ( $value) | |
unserialize ( $value) | |
Protected Member Functions inherited from Wikimedia\ObjectCache\MediumSpecificBagOStuff | |
cas ( $casToken, $key, $value, $exptime=0, $flags=0) | |
Set an item if the current CAS token matches the provided CAS token. | |
debug ( $text) | |
getExpirationAsTimestamp ( $exptime) | |
Convert an optionally relative timestamp to an absolute time. | |
getExpirationAsTTL ( $exptime) | |
Convert an optionally absolute expiry time to a relative time. | |
getSerialized ( $value, $key) | |
Get the serialized form a value, logging a warning if it involves custom classes. | |
isInteger ( $value) | |
Check if a value is an integer. | |
isRelativeExpiration ( $exptime) | |
makeLockKey ( $key) | |
makeValueOrSegmentList ( $key, $value, $exptime, $flags, &$ok) | |
Make the entry to store at a key (inline or segment list), storing any segments. | |
mergeViaCas ( $key, callable $callback, $exptime, $attempts, $flags) | |
resolveSegments ( $key, $mainValue) | |
Get and reassemble the chunks of blob at the given key. | |
tokensMatch ( $value, $otherValue) | |
updateOpStats (string $op, array $keyInfo) | |
Protected Member Functions inherited from Wikimedia\ObjectCache\BagOStuff | |
fieldHasFlags ( $field, $flags) | |
mergeFlagMaps (array $bags) | |
Merge the flag maps of one or more BagOStuff objects into a "lowest common denominator" map. | |
proxyCall (string $method, int $arg0Sig, int $resSig, array $genericArgs, BagOStuff $wrapper) | |
Call a method on behalf of wrapper BagOStuff instance. | |
setLastError ( $error) | |
Set the "last error" registry due to a problem encountered during an attempted operation. | |
Protected Attributes | |
Exception[] | $connFailureErrors = [] |
Map of (shard index => Exception) | |
float[] | $connFailureTimes = [] |
Map of (shard index => UNIX timestamps) | |
IMaintainableDatabase[] | $conns |
Map of (shard index => DB handle) | |
string false null | $dbDomain |
DB name used for keys using the LoadBalancer. | |
float | $lastGarbageCollect = 0 |
UNIX timestamp. | |
ILoadBalancer null | $loadBalancer |
callable null | $loadBalancerCallback |
Injected function which returns a LoadBalancer. | |
bool | $multiPrimaryMode |
Whether multi-primary mode is enabled. | |
int | $numTableShards = 1 |
Number of table shards to use on each server. | |
int | $purgeLimit = 100 |
Max expired rows to purge during randomized garbage collection. | |
int | $purgePeriod = 10 |
Average number of writes required to trigger garbage collection. | |
array[] | $serverInfos = [] |
(server index => server config) | |
string[] | $serverTags = [] |
(server index => tag/host name) | |
string | $tableName = 'objectcache' |
bool | $useLB = false |
Whether to use the LoadBalancer. | |
int | $writeBatchSize = 100 |
Protected Attributes inherited from Wikimedia\ObjectCache\MediumSpecificBagOStuff | |
array< string, array > | $locks = [] |
Map of (key => (class LOCK_* constant => value) | |
float | $maxLockSendDelay = 0.05 |
Seconds; maximum expected seconds for a lock ping to reach the backend. | |
int | $segmentationSize |
Bytes; chunk size of segmented cache values. | |
int | $segmentedValueMaxSize |
Bytes; maximum total size of a segmented cache value. | |
const | LOCK_DEPTH = 1 |
const | LOCK_EXPIRY = 3 |
const | LOCK_RCLASS = 0 |
const | LOCK_TIME = 2 |
const | METRIC_OP_ADD = 'add' |
const | METRIC_OP_CAS = 'cas' |
const | METRIC_OP_CHANGE_TTL = 'change_ttl' |
const | METRIC_OP_DECR = 'decr' |
const | METRIC_OP_DELETE = 'delete' |
const | METRIC_OP_GET = 'get' |
const | METRIC_OP_INCR = 'incr' |
const | METRIC_OP_SET = 'set' |
const | PASS_BY_REF = -1 |
Idiom for doGet() to return extra information by reference. | |
Protected Attributes inherited from Wikimedia\ObjectCache\BagOStuff | |
callable null | $asyncHandler |
int[] | $attrMap = [] |
Map of (BagOStuff:ATTR_* constant => BagOStuff:QOS_* constant) | |
string | $keyspace |
Default keyspace; used by makeKey() | |
int | $lastError = self::ERR_NONE |
BagOStuff:ERR_* constant of the last error that occurred. | |
int | $lastErrorId = 0 |
Error event sequence number of the last error that occurred. | |
LoggerInterface | $logger |
StatsFactory | $stats |
Additional Inherited Members | |
Public Attributes inherited from Wikimedia\ObjectCache\BagOStuff | |
const | MAX_CONFLICTS_ONE = 1 |
Abort after the first merge conflict. | |
const | READ_LATEST = 1 |
Bitfield constants for get()/getMulti(); these are only advisory. | |
const | READ_VERIFIED = 2 |
Promise that the caller handles detection of staleness. | |
const | WRITE_ALLOW_SEGMENTS = 16 |
Allow partitioning of the value if it is a large string. | |
const | WRITE_BACKGROUND = 64 |
If supported, do not block on write operation completion; instead, treat writes as succesful based on whether they could be buffered. | |
const | WRITE_CACHE_ONLY = 8 |
Bitfield constants for set()/merge(); these are only advisory. | |
const | WRITE_PRUNE_SEGMENTS = self::WRITE_ALLOW_SEGMENTS |
Delete all the segments if the value is partitioned. | |
Public Attributes inherited from Wikimedia\LightweightObjectStore\StorageAwareness | |
const | ATTR_DURABILITY = 2 |
Durability of writes; see QOS_DURABILITY_* (higher means stronger) | |
const | ATTR_EMULATION = 1 |
const | ERR_NO_RESPONSE = 1 |
Storage medium failed to yield a complete response to an operation. | |
const | ERR_NONE = 0 |
No storage medium error. | |
const | ERR_UNEXPECTED = 3 |
Storage medium operation failed due to usage limitations or an I/O error. | |
const | ERR_UNREACHABLE = 2 |
Storage medium could not be reached to establish a connection. | |
const | QOS_DURABILITY_DISK = 4 |
Data is saved to disk and writes do not usually block on fsync() | |
const | QOS_DURABILITY_NONE = 1 |
Data is never saved to begin with (blackhole store) | |
const | QOS_DURABILITY_RDBMS = 5 |
Data is saved to disk and writes usually block on fsync(), like a standard RDBMS. | |
const | QOS_DURABILITY_SCRIPT = 2 |
Data is lost at the end of the current web request or CLI script. | |
const | QOS_DURABILITY_SERVICE = 3 |
Data is lost once the service storing the data restarts. | |
const | QOS_UNKNOWN = INF |
Generic "unknown" value; useful for comparisons (always "good enough") | |
Static Protected Attributes inherited from Wikimedia\ObjectCache\BagOStuff | |
static int | $nextErrorMonitorId = 1 |
Next sequence number to use for watch/error events. | |
RDBMS-based caching module.
The following database sharding schemes are supported:
The following database replication topologies are supported:
Definition at line 54 of file SqlBagOStuff.php.
SqlBagOStuff::__construct | ( | $params | ) |
Create a new backend instance from parameters injected by ObjectCache::newFromParams()
The database servers must be provided by either the "server" parameter, the "servers" parameter or the "loadBalancer" parameter.
The parameters are as described at \\MediaWiki\\MainConfigSchema::ObjectCaches
except that:
array | $params |
|
Definition at line 144 of file SqlBagOStuff.php.
References $params.
SqlBagOStuff::createTables | ( | ) |
Create the shard tables on all databases.
This is typically called manually by a sysadmin via eval.php, e.g. for ParserCache:
This is different from $services->getParserCache()->getCacheStorage()->createTables()
, which would use the backend set via $wgParserCacheType, which shouldn't be set yet for the backend you are creating shard tables on. The expectation is to first add the new backend to $wgObjectCaches, run the above, and then enable it for live ParserCache traffic by setting $wgParserCacheType.
Definition at line 1802 of file SqlBagOStuff.php.
References Wikimedia\Rdbms\IReadableDatabase\getType(), Wikimedia\Rdbms\IDatabase\query(), and Wikimedia\Rdbms\Platform\ISQLPlatform\tableName().
SqlBagOStuff::deleteAll | ( | ) |
Delete content of shard tables in every server.
Return true if the operation is successful, false otherwise.
Definition at line 1537 of file SqlBagOStuff.php.
References Wikimedia\Rdbms\IDatabase\newDeleteQueryBuilder(), and wfDeprecated().
SqlBagOStuff::deleteObjectsExpiringBefore | ( | $timestamp, | |
?callable | $progress = null, | ||
$limit = INF, | |||
?string | $tag = null ) |
Delete all objects expiring before a certain date.
string | int | $timestamp | The reference date in MW or TS_UNIX format |
callable | null | $progress | Optional, a function which will be called regularly during long-running operations with the percentage progress as the first parameter. [optional] |
int | float | $limit | Maximum number of keys to delete [default: INF] |
string | null | $tag | Tag to purge a single shard only. This is only supported when server tags are used in configuration. |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 1367 of file SqlBagOStuff.php.
References Wikimedia\Rdbms\IDatabase\lock(), and Wikimedia\Rdbms\IDatabase\unlock().
Referenced by expireAll().
|
protected |
Insert an item if it does not already exist.
string | $key | |
mixed | $value | |
int | $exptime | |
int | $flags | Bitfield of BagOStuff::WRITE_* constants (since 1.33) |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 225 of file SqlBagOStuff.php.
|
protected |
Set an item if the current CAS token matches the provided CAS token.
mixed | $casToken | CAS token from an existing version of the key |
string | $key | |
mixed | $value | |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 239 of file SqlBagOStuff.php.
|
protected |
string | $key | |
int | $exptime | |
int | $flags |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 253 of file SqlBagOStuff.php.
References Wikimedia\ObjectCache\BagOStuff\getCurrentTime().
SqlBagOStuff::doChangeTTLMulti | ( | array | $keys, |
$exptime, | |||
$flags = 0 ) |
string[] | $keys | List of keys |
int | $exptime | TTL or UNIX timestamp |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 332 of file SqlBagOStuff.php.
References Wikimedia\ObjectCache\BagOStuff\getCurrentTime().
|
protected |
Delete an item.
string | $key | |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 215 of file SqlBagOStuff.php.
References Wikimedia\ObjectCache\BagOStuff\getCurrentTime().
|
protected |
string[] | $keys | List of keys |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 322 of file SqlBagOStuff.php.
References Wikimedia\ObjectCache\BagOStuff\getCurrentTime().
|
protected |
Get an item.
The CAS token should be null if the key does not exist or the value is corrupt
string | $key | |
int | $flags | Bitfield of BagOStuff::READ_* constants [optional] |
mixed | &$casToken | CAS token if MediumSpecificBagOStuff::PASS_BY_REF [returned] |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 184 of file SqlBagOStuff.php.
References unserialize(), and Wikimedia\ObjectCache\MediumSpecificBagOStuff\updateOpStats().
|
protected |
Get an associative array containing the item for each of the keys that have items.
string[] | $keys | List of keys |
int | $flags | Bitfield; supports READ_LATEST [optional] |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 282 of file SqlBagOStuff.php.
References unserialize(), and Wikimedia\ObjectCache\MediumSpecificBagOStuff\updateOpStats().
|
protected |
string | $key | |
int | $exptime | |
int | $step | |
int | $init | |
int | $flags |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 263 of file SqlBagOStuff.php.
References Wikimedia\ObjectCache\BagOStuff\getCurrentTime().
SqlBagOStuff::doLock | ( | $key, | |
$timeout = 6, | |||
$exptime = 6 ) |
string | $key | |
int | $timeout | Lock wait timeout; 0 for non-blocking [optional] |
int | $exptime | Lock time-to-live 1 day maximum [optional] |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 1558 of file SqlBagOStuff.php.
References Wikimedia\Rdbms\IDatabase\lock().
|
protected |
Set an item.
string | $key | |
mixed | $value | |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 205 of file SqlBagOStuff.php.
References Wikimedia\ObjectCache\BagOStuff\getCurrentTime().
|
protected |
mixed[] | $data | Map of (key => value) |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 307 of file SqlBagOStuff.php.
References Wikimedia\ObjectCache\BagOStuff\getCurrentTime().
SqlBagOStuff::doUnlock | ( | $key | ) |
string | $key |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 1579 of file SqlBagOStuff.php.
References Wikimedia\Rdbms\IDatabase\unlock().
SqlBagOStuff::expireAll | ( | ) |
Definition at line 1362 of file SqlBagOStuff.php.
References deleteObjectsExpiringBefore(), Wikimedia\ObjectCache\BagOStuff\getCurrentTime(), and wfDeprecated().
|
protected |
Make a cache key for the given keyspace and components.
Subclasses may override this method in order to apply different escaping, or to deal with size constraints (such as MemcachedBagOStuff). For example by converting long components into hashes.
If you override this method, you MUST override ::requireConvertGenericKey() to return true. This ensures that wrapping classes (e.g. MultiWriteBagOStuff) know to re-encode keys before calling read/write methods. See also ::proxyCall().
string | $keyspace | |
string[] | int[] | $components | Key group and other components |
Reimplemented from Wikimedia\ObjectCache\BagOStuff.
Definition at line 1596 of file SqlBagOStuff.php.
References Wikimedia\ObjectCache\BagOStuff\$keyspace.
|
protected |
Whether ::proxyCall() must re-encode cache keys before calling read/write methods.
Reimplemented from Wikimedia\ObjectCache\BagOStuff.
Definition at line 1622 of file SqlBagOStuff.php.
|
protected |
mixed | $value |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 1626 of file SqlBagOStuff.php.
|
protected |
string | int | false | $value |
Reimplemented from Wikimedia\ObjectCache\MediumSpecificBagOStuff.
Definition at line 1640 of file SqlBagOStuff.php.
Referenced by doGet(), and doGetMulti().
|
protected |
Map of (shard index => Exception)
Definition at line 88 of file SqlBagOStuff.php.
|
protected |
Map of (shard index => UNIX timestamps)
Definition at line 86 of file SqlBagOStuff.php.
|
protected |
Map of (shard index => DB handle)
Definition at line 84 of file SqlBagOStuff.php.
|
protected |
DB name used for keys using the LoadBalancer.
Definition at line 60 of file SqlBagOStuff.php.
|
protected |
UNIX timestamp.
Definition at line 69 of file SqlBagOStuff.php.
|
protected |
Definition at line 58 of file SqlBagOStuff.php.
|
protected |
Injected function which returns a LoadBalancer.
Definition at line 56 of file SqlBagOStuff.php.
|
protected |
Whether multi-primary mode is enabled.
Definition at line 81 of file SqlBagOStuff.php.
|
protected |
Number of table shards to use on each server.
Definition at line 75 of file SqlBagOStuff.php.
|
protected |
Max expired rows to purge during randomized garbage collection.
Definition at line 73 of file SqlBagOStuff.php.
|
protected |
Average number of writes required to trigger garbage collection.
Definition at line 71 of file SqlBagOStuff.php.
|
protected |
(server index => server config)
Definition at line 65 of file SqlBagOStuff.php.
|
protected |
(server index => tag/host name)
Definition at line 67 of file SqlBagOStuff.php.
|
protected |
Definition at line 79 of file SqlBagOStuff.php.
|
protected |
Whether to use the LoadBalancer.
Definition at line 62 of file SqlBagOStuff.php.
|
protected |
Definition at line 77 of file SqlBagOStuff.php.