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https://issues.apache.org/jira/browse/SOLR-5986?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14062228#comment-14062228
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Jim Walker commented on SOLR-5986:
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Steve, I wonder why you would have to restart the replica? I presume this is
because that is your only recourse to stop a query that might take days to
complete?
If a query takes that long and is ignoring a specified timeout, that seems like
it's own issue that needs resolution.
IMHO, the primary goal should be to make SolrCloud clusters more resilient to
performance degradations caused by such nasty queries described above.
The circuit-breaker approach in the linked ES tickets is clever, but it does
not seem to be as generally applicable as the ability to view all running
queries with an option to stop them. For example, it seems the linked ES
circuit breaker will only trigger for issues deriving from loading too much
field data. The problem described above may result from this cause, or any
number of other causes.
My preference would be to have a response mechanism that 1) applies broadly and
2) a dev-ops guy can execute in a UI like Solr Admin, or even by API.
> Don't allow runaway queries from harming Solr cluster health or search
> performance
> ----------------------------------------------------------------------------------
>
> Key: SOLR-5986
> URL: https://issues.apache.org/jira/browse/SOLR-5986
> Project: Solr
> Issue Type: Improvement
> Components: search
> Reporter: Steve Davids
> Priority: Critical
> Fix For: 4.9
>
>
> The intent of this ticket is to have all distributed search requests stop
> wasting CPU cycles on requests that have already timed out or are so
> complicated that they won't be able to execute. We have come across a case
> where a nasty wildcard query within a proximity clause was causing the
> cluster to enumerate terms for hours even though the query timeout was set to
> minutes. This caused a noticeable slowdown within the system which made us
> restart the replicas that happened to service that one request, the worst
> case scenario are users with a relatively low zk timeout value will have
> nodes start dropping from the cluster due to long GC pauses.
> [~amccurry] Built a mechanism into Apache Blur to help with the issue in
> BLUR-142 (see commit comment for code, though look at the latest code on the
> trunk for newer bug fixes).
> Solr should be able to either prevent these problematic queries from running
> by some heuristic (possibly estimated size of heap usage) or be able to
> execute a thread interrupt on all query threads once the time threshold is
> met. This issue mirrors what others have discussed on the mailing list:
> http://mail-archives.apache.org/mod_mbox/lucene-solr-user/200903.mbox/%[email protected]%3E
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