Hi > According to the exception log of the following topic, a client node joins the cluster and blocks a SQL query on the transactional cache. Is this true? > Now it seems that the relevant explanations are confusing?
Looking at your stack traces it seems that the cache you accessed in the SQL query was stopped right before the new client node is joined. All topology events are processed one-by-one, so the initial blocking time was caused by cache stop PME rather than client node join. However, SQL and cache endpoints have different mechanisms for dealing with partitions affinity. My explanations in this topic were about only cache operations. For SQL it seems that client node join can still block SQL query for a time, but client PME is very fast, so its impact should be minimal. сб, 12 дек. 2020 г. в 04:34, 38797715 <38797...@qq.com>: > Hi, > > According to the exception log of the following topic, a client node joins > the cluster and blocks a SQL query on the transactional cache. Is this true? > > > http://apache-ignite-users.70518.x6.nabble.com/Failed-to-wait-for-affinity-ready-future-for-topology-version-AffinityTopologyVersion-td34823.html > > Now it seems that the relevant explanations are confusing? > 在 2020/12/11 下午8:21, Pavel Kovalenko 写道: > > Hi, > > I think it's wrong information on the wiki that PME is not triggered for > some cases. It should be fixed. > Actually, PME is triggered in all cases but for some of them it doesn't > block cache operations or the time of blocking is minimized. > Most optimizations for minimizing the blocking time of PME have been done > in Ignite 2.8. > > Thick client join/left PME - doesn't block operations at all. > > Other events can be ordered by their potential blocking time: > 1. Non-baseline node left/join - minimal > 2. Baseline node stop/left > 3. Baseline node join > 4. Baseline change - heaviest operation > > > *for the end user , is this invoked when we do ignite.getOrCreate( xx ) > and ignite.cache(xx )* > > Yes. > > пт, 11 дек. 2020 г. в 14:55, VeenaMithare <v.mith...@cmcmarkets.com>: > >> Hi , >> >> >> I can see the triggers for PME initiation here : >> >> https://cwiki.apache.org/confluence/display/IGNITE/%28Partition+Map%29+Exchange+-+under+the+hood >> >> Triggers >> Events which causes exchange >> >> Topology events: >> >> Node Join (EVT_NODE_JOINED) - new node discovered and joined topology >> (exchange is done after a node is included into the ring). This event >> doesn't trigger the PME if a thick client connects the cluster and an >> Ignite >> version is 2.8 or later. >> >> >> --> *This means in ignite 2.8 or higher, this is triggered only if nodes >> that participate in the baseline topology are added ?* >> >> >> Node Left (EVT_NODE_LEFT) - correct shutdown with call ignite.close. This >> event doesn't trigger the PME in Ignite 2.8 and later versions if a node >> belonging to an existing baseline topology leaves. >> >> --> *This means this is not triggered at all 2.8.1 or higher if shutdown >> cleanly ? i.e. if this is called : Ignition.stop(false) * >> >> >> Node Failed (EVT_NODE_FAILED) - detected unresponsive node, probably >> crashed >> and is considered failed >> >> --> *This means this is triggered at all 2.8.1 or higher for baseline >> nodes >> or any thick client node ?* >> >> Custom events: >> >> Activation / Deactivation / Baseline topology set - >> ChangeGlobalStateMessage >> Dynamic cache start / Dynamic cache stop - DynamicCacheChangeBatch >> >> --> *for the end user , is this invoked when we do ignite.getOrCreate( xx >> ) >> and ignite.cache(xx )* >> >> >> Snapshot create / restore - SnapshotDiscoveryMessage >> Global WAL enable / disable - WalStateAbstractMessage >> Late affinity assignment - CacheAffinityChangeMessage >> >> >> regards, >> Veena. >> >> >> >> -- >> Sent from: http://apache-ignite-users.70518.x6.nabble.com/ >> >
