Thanks, Edward, for clues. What bothers me is newSearcher start, warming, cache clear... all that CPU consuming stuff in my heavy-indexing scenario. With NRT I had autoSoftCommit: <maxTime>300000</maxTime>. So I had new Searcher no more than every 5 min on every replica. To have more or less the same effect with TLOG - PULL collection, I suppose, I have to have <autoCommit> : <maxTime>300000</maxTime> (yes, I understand that newSearchers start asynchronously on leader and replicas) Am I right? -- Vadim
> -----Original Message----- > From: Edward Ribeiro [mailto:edward.ribe...@gmail.com] > Sent: Sunday, December 09, 2018 12:42 AM > To: solr-user@lucene.apache.org > Subject: Re: Soft commit and new replica types > > Some insights in the new replica types below: > > On Sat, December 8, 2018 08:42, Vadim Ivanov < > vadim.iva...@spb.ntk-intourist.ru wrote: > > > > > From Ref guide we have: > > " NRT is the only type of replica that supports soft-commits..." > > "If TLOG replica does become a leader, it will behave the same as if it > > was a NRT type of replica." > > Does it mean, that if we do not have NRT replicas in the cluster then > > autoSoftCommit section in solconfig.xml Ignored completely (even on TLOG > > leader)? > > > > No, not completely. Both TLOG and PULL nodes will periodically poll the > leader for changes in index segments' files and download those segments > from the leader. If hard commit max time is defined in solrconfig.xml the > polling interval of each replica will be half that value. Or else if the > soft commit max time is defined then the replicas will use half the soft > commit max time as the interval. If neither are defined then the poll > interval will be 3 seconds (hard coded). See here: > https://github.com/apache/lucene- > solr/blob/75b183196798232aa6f2dcaaaab117f309119053/solr/core/src/java/o > rg/apache/solr/cloud/ReplicateFromLeader.java#L68-L77 > > If the TLOG is the leader it will index locally and append the doc to > transaction log as a NRT node would do as well as it will synchronously > replicate the data to other TLOG replicas' transaction logs (PULL nodes > don't have transaction logs). But TLOG/PULL replicas doesn't support soft > commits nor real time gets, afaik. > > > > > > <autoSoftCommit> > > <maxTime>60000</maxTime> > > </autoSoftCommit> > > > > Should we say that in autoCommit section openSearcher is always true in > > that case? > > > <autoCommit> > <maxDocs>10000</maxDocs> > <maxTime>30000</maxTime> > <maxSize>512m</maxSize> > <openSearcher>false</openSearcher> > </autoCommit> > > Does it mean that new Searcher always starts on all replicas when hard > commit happens on leader? > > > Nope. Or at least, the searcher is not synchronously created. Each non > leader replica will periodically fetch the index changes from the leader > and open a new searcher to reflect those changes as seen here: > https://github.com/apache/lucene- > solr/blob/75b183196798232aa6f2dcaaaab117f309119053/solr/core/src/java/o > rg/apache/solr/handler/IndexFetcher.java#L653 > But it's important to note that the potential delay between the leader's > hard commit and the other replicas fetching those changes from the leader > and opening a new searcher to reflect latest changes. > > PS: I am still digging these new replica types so I can have misunderstood > or missed some aspect of it. > > Regards, > Edward
