We have not set any shard.preference, and I also think preferLocal defaults to false, i.e random
Earlier we had 2 shares for the same collection (both existed on both nodes) and then requests were distributed to both nodes. That’s why, when we went to 1 shard, I was wondering if the “single-shard” code path perhaps never attempts to utilize replicas?? But have not looked in code yet. Guess next step is to setup a small local test cluster and see what happens. Jan Høydahl > 10. mar. 2021 kl. 15:46 skrev Michael Gibney <mich...@michaelgibney.net>: > > You say not "anything fancy" -- depending on how you define "fancy", if you > have an explicit `shards.preference` param, based on the version you're > running (8.4) you might also take a look at > https://issues.apache.org/jira/browse/SOLR-14471. (If SOLR-14471 is the > problem, removing the explicit `shards.preference` param should restore > default "shuffling" routing). > > I haven't dug too deep, but it looks like for 8.4 preferLocalShards > actually defaults to false? I might be missing something though: > https://github.com/apache/lucene-solr/blob/releases/lucene-solr/8.4.1/solr/solrj/src/java/org/apache/solr/client/solrj/routing/RequestReplicaListTransformerGenerator.java#L85 > > > >> On Wed, Mar 10, 2021 at 9:10 AM Houston Putman <houstonput...@gmail.com> >> wrote: >> >> I could be wrong, but i dont think preferLocalShards is the default in >> multi-shard use cases. >> >>> On Wed, Mar 10, 2021 at 9:07 AM Mike Drob <md...@mdrob.com> wrote: >>> >>> I believe a server will always try to prefer local cores. Can you do an >>> experiment with 3 nodes, and send http queries to the node not hosting >> any >>> replicas? That should confirm the balanced distribution. >>> >>> If you have multiple shards, the receiving server will forward the >> requests >>> for shards it doesn’t have, but would still prefer local shards when they >>> are available. >>> >>> On Wed, Mar 10, 2021 at 8:00 AM Jan Høydahl <jan....@cominvent.com> >> wrote: >>> >>>> Hi, >>>> >>>> A client has a SolrCloud 8.4 setup with two nodes, and one collection >>> with >>>> one shard and replicationFactor=2. >>>> Of course we want search traffic to be evenly distributed between the >> two >>>> replicas. >>>> The client is using plain HTTP requests, no SolrJ or anything fancy, >> and >>>> sends all requests to one of the two nodes. >>>> I was expecting Solr to forward about 50% of those requests to the >> other >>>> replica, but it is serving them all locally. >>>> >>>> I know we can setup an LB in front or re-program the client to do round >>>> robin, but that is not my question. >>>> Is the select-random-replica logic only active when we have a sharded >>>> oollection, and not for a single-shard? >>>> >>>> Jan >>> >>
