CODEWITHSUNDEEP
performancesearchsolr8solrconfig
BReddy
BReddy

Reputation: 13

Solr 8 Performance issue on restart

I am trying to figure out why the solr core, doesn't respond upon a restart of solr daemon . I have multiple cores , and the configuration is a leader / follower approach, each core serving certain business needs.

When I restart solr on the server, the cores that have <100K documents, show up immediately when they are queried. But there are 2 specific cores, where we have around 2 to 3M documents, that takes around 2 minutes to be available for querying.

I know about the warmup / first searcher..etc. But those queries are commented out, so it should not be running the first searcher queries.

I noticed that when I turn this to "true" ( the default value is false)

<useColdSearcher>true</useColdSearcher>

The core that has 2M plus documents show up immediately on a restart of solr.

This never happened in solr 6.6 world, Is this something new in solr 8.x ?

Can someone who experienced this throw some light on this.

In solr 6.x we had the defaults and the cores were available right away. But the same settings in solr 8.11 , doesn't make the core available after a restart.

thanks in advance B

Upvotes: 0

Views: 261

Answers (1)

BReddy
BReddy

Reputation: 13

Since I did not get an answer ,I tried the following experiments.

Made a change to the useColdSearcher to true and restarted the core, then the core started right away and started serving the request.

I also ran a load test with the configuration "useColdSearcher=true", and I did not see that much of a difference. I tried this load test with both true and false.

The default option in the solrconfig is useColdSearcher is false , so the same index, similar configuration in solr 6 started the searcher quick, but not in solr 8, until I made the above change.

I experimented with questions on chatGPT as well. The response in bold. The "useColdSearcher" setting in Solr can potentially slow down the process of registering a new searcher in Solr 8.x, but it shouldn't have any effect on Solr 6.x.

It's important to note that useColdSearcher is only available for SolrCloud mode and not for standalone mode. This setting is not available in Solr 6.x, so it wouldn't have any impact on the registration of new searchers in that version.

Since my setup is a leader ->follower , I guess I should be good to set the useColdSearcher to true.

One should try the above tests before taking their course of action. But it worked for me. So wanted to post the answer.

Upvotes: 0

Related Questions