* Keys that take a long time to generate would run into
the MAX_SNAPSHOT_LAG check and have set() no-op. This
would be fine except that leaves no key there to figure
out the time since expiry and therefore whether to use
the mutex, so it didn't. This now saves the keys but with
a FLG_STALE bit set, making the next caller that sees it
perform a regeneration (unless it can't get the mutex).
* Bumped LOCK_TTL so that keys can stay locked much longer.
* This is easy to test via sleep(5) in tagUsageStatistics()
and two Special:Tags browser tabs.
Bug: T91535
Change-Id: I549e70ace3d2e7da40d3c4346ebacc36024cd522
Also consistently use self:: instead of BagOStuff:: for constants
referenced within the BagOStuff class.
Change-Id: I20fde9fa5cddcc9e92fa6a02b05dc7effa846742
* In the common ~0 second lag case, transactions up to ~7 seconds
long will have normal set() behavior (instead of just ~5 seconds).
* Like wise with ~0 second transactions tolerating ~7 seconds of
lag (instead of just ~5).
* The lower hold-off time lets caching resume 3 seconds sooner.
Change-Id: I21e2a0a6915492cec422b6a6af5541937745c15b
This generally only effects wikis with no slave DBs,
but also matters if the master has non-zero LB load.
If the master ends up being used for DB_SLAVE, care
should be shown for cache-aside writes
Interesting WAN cache events are now logged.
Change-Id: I2cd8e84138263c13ea23beb9ab3d7562340e1fd3
Also removed a few MW dependencies from MemcachedPeclBagOStuff.
It still uses an IP class method, so it has to stay for now.
Change-Id: I8c5c83046c58fb58091d6ce11b2385208262460f
For the sake of safety and correctness, the following BagOStuff::makeKey()
invocations should return distinct keys:
$cache->makeKey( 'ab:', 'cd' );
$cache->makeKey( 'ab', ':cd' );
That is not currently the case, because while we use ':' as a key path
separator, we don't escape ':' in the input supplied to makeKey(). So, make
BagOStuff::makeKeyInternal() URL-encode colons.
To prevent this from messing up the max. key length calculations, reproduce
this logic in MemcachedBagOStuff::makeKeyInternal(), in lieu of having the
method call its parent.
Change-Id: I83ea7e7336a1c9e64aa42284c2517089a736efe5
* This blocks on writing to all replicas
and returns false if any failed.
* This is useful if ChronologyProtector is to work across
domains by having the writes go everywhere so that later
reads will see them (and be local at the same time).
* Redundant doc comments were also removed.
Change-Id: I9ed098d563c64dba605e7809bc96731da3b3e79d
* Add a string `keyspace` member to BagOStuff instances. The default
implementation, meant for simple key/value stores, treats the key space
as a string prefix to prepend to keys. By default, its value is `local`,
but any instance created via ObjectCache::newFromParams() (or or one of
its callers) will have that default to $wgCachePrefix / wfWikiID().
* Add `makeKey` and `makeGlobalKey` methods to the base BagOStuff class.
These methods are not static to allow for BagOStuff types which require
a configured instance to know the underlying storage engine's key semantics.
* Make wfMemcKey() and wfGlobalCacheKey() delegate to these methods on the main
ObjectCache instance.
Change-Id: Ib7fc2f939be3decfa97f66af8c2431c51039905f
* Make getWithSetCallback() accept a TTL field for this
* Make ChangeTag callers use this flag to avoid hundreds of
duplicate queries at Special:Tags
Change-Id: Ic1ed28294f5d557e02f39a7f20d36766244b9ded
This fixes the default $oldOpts value for the case when
$opts is given check keys and no $oldOpts value is passed
in. In that case, the getWithSetCallback() method
variable $opts would be null instead of array().
Change-Id: I825062533478b37766511aae1d06dd4b81f8dba1
* Put 'checkKeys' param in opts array instead of as a separate parameter.
It's neat to not have to skip unnamed/positional arguments that are optional.
* Move TTL to be before callback instead of after. This avoids dangling integers
toward the bottom of a large code block that have no obvious meaning.
Matches BagOStuff::getWithSetCallback.
Add unit test for lockTSE to confirm
Change-Id: I60d6b64fc5dff14108741bafe801fd1fde16d1df
This better handles values that take a long time to
generate. For example if it took 10 sec, then the old
value would not regenerate in time. 30 is a good, high,
value that is the default PHP timeout.
Change-Id: I2e4372bf4c6d28d09347012926d8c0a9deda4183
* Callers of get() no longer have to contend with
the annoying $casToken parameter, which is there
but totally unusable to non-BagOStuff code.
* The default get() now delegates to doGet(),
which callers must implement instead. They can
ignore the overhead of generating $casToken if
they do not implement cas(), which applies to
callers that use the stock merge(). If cas() is
used for merge(), then getWithToken() must be
implemented.
* Also add BagOStuff::READ_LATEST to mergeViaCas()
for sanity, as that missing before.
Likewise with mergeViaLock().
Change-Id: I4efce6a9ab4b1eadd2f161dff641004a7239c516
* This gets lag information that is useful when
the calling code is about to run queries that
will have their results cached.
* This is now used in place of trxTimestamp() for
WANObjectCache set() and getWithSetCallback().
* The WAN cache will use a low TTL if the lag is
too high to avoid caching stale data for weeks.
* Bumped MAX_COMMIT_DELAY as nothing enforces it.
Bug: T113204
Change-Id: I2a95b4088cff42d6e980351555f81a4b13519e24
* This lets multiwrite backends upgrade cached items
to higher tiers using UPGRADE_TTL.
* This is useful for memcached/sql tiers or apc/memcached.
Change-Id: I34b30ce8b54f8de36429d48c80f6768aed310272
* Doxygen needs this or the paragraph ends up in the
last bullet point
* Also removed some redundant comments
Change-Id: Ie4bf2b67fff27ecad5f24f55688161fe484c300d
* This can avoid some stale write race conditions
* Made use of this option in a few key places
* HOLDOFF_TTL was also bumped
Change-Id: I83505a59cce0119e456191c3100f7d97bc86bdbf
