*
* ### Deploying WANObjectCache
*
- * There are three supported ways to set up broadcasted operations:
+ * There are two supported ways to set up broadcasted operations:
*
- * - A) Configure the 'purge' EventRelayer to point to a valid PubSub endpoint
- * that has subscribed listeners on the cache servers applying the cache updates.
- * - B) Omit the 'purge' EventRelayer parameter and set up mcrouter as the underlying cache
- * backend, using a memcached BagOStuff class for the 'cache' parameter. The 'region'
- * and 'cluster' parameters must be provided and 'mcrouterAware' must be set to `true`.
+ * - A) Set up mcrouter as the underlying cache backend, using a memcached BagOStuff class
+ * for the 'cache' parameter. The 'region' and 'cluster' parameters must be provided
+ * and 'mcrouterAware' must be set to `true`.
* Configure mcrouter as follows:
* - 1) Use Route Prefixing based on region (datacenter) and cache cluster.
* See https://github.com/facebook/mcrouter/wiki/Routing-Prefix and
* configure 'set' and 'delete' operations to go to all servers in the cache
* cluster, instead of just one server determined by hashing.
* See https://github.com/facebook/mcrouter/wiki/List-of-Route-Handles.
- * - C) Omit the 'purge' EventRelayer parameter and set up dynomite as cache middleware
- * between the web servers and either memcached or redis. This will broadcast all
- * key setting operations, not just purges, which can be useful for cache warming.
- * Writes are eventually consistent via the Dynamo replication model.
- * See https://github.com/Netflix/dynomite.
+ * - B) Set up dynomite as a cache middleware between the web servers and either memcached
+ * or redis and use it as the underlying cache backend, using a memcached BagOStuff
+ * class for the 'cache' parameter. This will broadcast all key setting operations,
+ * not just purges, which can be useful for cache warming. Writes are eventually
+ * consistent via the Dynamo replication model. See https://github.com/Netflix/dynomite.
*
* Broadcasted operations like delete() and touchCheckKey() are done asynchronously
* in all datacenters this way, though the local one should likely be near immediate.
protected $cache;
/** @var MapCacheLRU[] Map of group PHP instance caches */
protected $processCaches = [];
- /** @var string Purge channel name */
- protected $purgeChannel;
- /** @var EventRelayer Bus that handles purge broadcasts */
- protected $purgeRelayer;
/** @bar bool Whether to use mcrouter key prefixing for routing */
protected $mcrouterAware;
/** @var string Physical region for mcrouter use */
/** @var float Unix timestamp of the oldest possible valid values */
protected $epoch;
- /** @var int ERR_* constant for the "last error" registry */
- protected $lastRelayError = self::ERR_NONE;
-
/** @var int Callback stack depth for getWithSetCallback() */
private $callbackDepth = 0;
/** @var mixed[] Temporary warm-up cache */
const PC_PRIMARY = 'primary:1000'; // process cache name and max key count
- const DEFAULT_PURGE_CHANNEL = 'wancache-purge';
-
/**
* @param array $params
* - cache : BagOStuff object for a persistent cache
- * - channels : Map of (action => channel string). Actions include "purge".
- * - relayers : Map of (action => EventRelayer object). Actions include "purge".
* - logger : LoggerInterface object
* - stats : LoggerInterface object
* - asyncHandler : A function that takes a callback and runs it later. If supplied,
*/
public function __construct( array $params ) {
$this->cache = $params['cache'];
- $this->purgeChannel = $params['channels']['purge'] ?? self::DEFAULT_PURGE_CHANNEL;
- $this->purgeRelayer = $params['relayers']['purge'] ?? new EventRelayerNull( [] );
$this->region = $params['region'] ?? 'main';
$this->cluster = $params['cluster'] ?? 'wan-main';
$this->mcrouterAware = !empty( $params['mcrouterAware'] );
* @return int ERR_* class constant for the "last error" registry
*/
final public function getLastError() {
- if ( $this->lastRelayError ) {
- // If the cache and the relayer failed, focus on the latter.
- // An update not making it to the relayer means it won't show up
- // in other DCs (nor will consistent re-hashing see up-to-date values).
- // On the other hand, if just the cache update failed, then it should
- // eventually be applied by the relayer.
- return $this->lastRelayError;
- }
-
$code = $this->cache->getLastError();
switch ( $code ) {
case BagOStuff::ERR_NONE:
*/
final public function clearLastError() {
$this->cache->clearLastError();
- $this->lastRelayError = self::ERR_NONE;
}
/**
$this->makePurgeValue( $this->getCurrentTime(), self::HOLDOFF_NONE ),
$ttl
);
- } elseif ( $this->purgeRelayer instanceof EventRelayerNull ) {
+ } else {
// This handles the mcrouter and the single-DC case
$ok = $this->cache->set(
$key,
$this->makePurgeValue( $this->getCurrentTime(), self::HOLDOFF_NONE ),
$ttl
);
- } else {
- $event = $this->cache->modifySimpleRelayEvent( [
- 'cmd' => 'set',
- 'key' => $key,
- 'val' => 'PURGED:$UNIXTIME$:' . (int)$holdoff,
- 'ttl' => max( $ttl, self::TTL_SECOND ),
- 'sbt' => true, // substitute $UNIXTIME$ with actual microtime
- ] );
-
- $ok = $this->purgeRelayer->notify( $this->purgeChannel, $event );
- if ( !$ok ) {
- $this->lastRelayError = self::ERR_RELAY;
- }
}
return $ok;
// See https://github.com/facebook/mcrouter/wiki/Multi-cluster-broadcast-setup
// Wildcards select all matching routes, e.g. the WAN cluster on all DCs
$ok = $this->cache->delete( "/*/{$this->cluster}/{$key}" );
- } elseif ( $this->purgeRelayer instanceof EventRelayerNull ) {
+ } else {
// Some other proxy handles broadcasting or there is only one datacenter
$ok = $this->cache->delete( $key );
- } else {
- $event = $this->cache->modifySimpleRelayEvent( [
- 'cmd' => 'delete',
- 'key' => $key,
- ] );
-
- $ok = $this->purgeRelayer->notify( $this->purgeChannel, $event );
- if ( !$ok ) {
- $this->lastRelayError = self::ERR_RELAY;
- }
}
return $ok;
dépôts / lhc / web / wiklou.git / blobdiff