Re: Proposal to use AffinityPlacementFactory as default in 9.0

+1. > On 29 Apr 2021, at 17:30, Ilan Ginzburg wrote: > > Expliciting (I think) your suggestion from the Slack thread Jan: > Add support for a new solr.xml config called something like > forceDefaultLegacyPlacementStrategy > Do not add anything in solr.xml > At runtime: > If a placement plugin i

Re: Proposal to use AffinityPlacementFactory as default in 9.0

The new code has no notion of existing collections so that can’t be an issue. It relies on detailed knowledge of the collection for which the Collection API is working, a related collection when applicable, and per node metrics/system properties. Ilan On Thu 29 Apr 2021 at 19:27, Gus Heck wrote:

Re: Proposal to use AffinityPlacementFactory as default in 9.0

IIRC it wasn't the nodes calculated, but rather the number of collections already in the cluster that caused the issue. See https://issues.apache.org/jira/browse/SOLR-14665 On Thu, Apr 29, 2021 at 1:09 PM Ilan Ginzburg wrote: > Yes Gus, this was verified, AB did some work around this. > Slowdown

Re: Proposal to use AffinityPlacementFactory as default in 9.0

Yes Gus, this was verified, AB did some work around this. Slowdown is linear on all cardinalities IIRC and absolute values are low. For example computing placement of 10K replicas in less than 1 sec on 5000 nodes, less than 3 sec on a 20K nodes cluster, placing 200K replicas on 5000 nodes, most unf

Re: Proposal to use AffinityPlacementFactory as default in 9.0

Possibly it was discussed elsewhere or in related tickets and I missed it, but has the scaling scenario that caused problems (time to create collections increasing linearly with increasing number of collections) been tested and compared with the result that lead to deprecation of autoscaling? On T

Re: Proposal to use AffinityPlacementFactory as default in 9.0

Expliciting (I think) your suggestion from the Slack thread Jan: - Add support for a new solr.xml config called something like forceDefaultLegacyPlacementStrategy - Do not add anything in solr.xml At runtime: - If a placement plugin is explicitly configured (existing plugin config

Proposal to use AffinityPlacementFactory as default in 9.0

Bringing over a discussion from Slack In 9.0, the old Autoscaling is gone, and instead we have cluster level "Placement Plugins", see https://nightlies.apache.org/Solr/Solr-reference-guide-main/replica-placement-plugins.html The