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https://issues.apache.org/jira/browse/SOLR-5986?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Anshum Gupta updated SOLR-5986:
-------------------------------
    Attachment: SOLR-5986.patch

New patch with the same approach but a few things fixed.

This uses timeAllowed (also used by the TimeLimitingCollector) to timeout 
queries during rewrite. Here's the fine print though, both the 
TimeLimitingCollected manage their own counter for the clock i.e. The maximum 
time that a query could run for is (2 * timeAllowed + Delta), where Delta is 
the time used for anything other than query expansion and collection.

I think this should be ok, specially considering the intention is to make sure 
that the request is killed and doesn't run forever.
There's always room for improvement though and we might want to share the same 
counter/offset/timeout so it's more predictable.

P.S: I'm still running the pre-commit to check if I'm missing something and 
would then run the solr+lucene tests again.

> 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
>            Assignee: Anshum Gupta
>            Priority: Critical
>             Fix For: 4.10
>
>         Attachments: SOLR-5986.patch, SOLR-5986.patch
>
>
> 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/%3c856ac15f0903272054q2dbdbd19kea3c5ba9e105b...@mail.gmail.com%3E



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