Re: Why does Solr sort on _docid_ with rows=0 ?
Thanks Hoss. Yes, that jira seems like a good one to fix. And the variable name definitely does not explain why it will not cause any sort operation. -SG On Mon, Mar 2, 2020 at 10:06 AM Chris Hostetter wrote: > : docid is the natural order of the posting lists, so there is no sorting > effort. > : I expect that means “don’t sort”. > > basically yes, as documented in the comment right above hte lines of code > linked to. > > : > So no one knows this then? > : > It seems like a good opportunity to get some performance! > > The variable name is really stupid, but the 'solrQuery' variable you see > in the code is *only* ever used for 'checkAZombieServer()' ... which > should only be called when a server hasn't been responding to other (user > initiated requests) > > : >> I see a lot of such queries in my Solr 7.6.0 logs: > > If you are seeing a lot of those queries, then there are other problems in > your cluster you should investigate -- that's when/why LBSolrClient does > this query -- to see if the server is responding. > > : >> *path=/select > : >> > params={q=*:*=false=_docid_+asc=0=javabin=2} > : >> hits=287128180 status=0 QTime=7173* > > that is an abnormally large number of documents to have in a single shard. > > : >> If you want to check a zombie server, shouldn't there be a much less > : >> expensive way to do a health-check instead? > > Probably yes -- i've opened SOLR-14298... > > https://issues.apache.org/jira/browse/SOLR-14298 > > > > -Hoss > http://www.lucidworks.com/
Re: Why does Solr sort on _docid_ with rows=0 ?
: docid is the natural order of the posting lists, so there is no sorting effort. : I expect that means “don’t sort”. basically yes, as documented in the comment right above hte lines of code linked to. : > So no one knows this then? : > It seems like a good opportunity to get some performance! The variable name is really stupid, but the 'solrQuery' variable you see in the code is *only* ever used for 'checkAZombieServer()' ... which should only be called when a server hasn't been responding to other (user initiated requests) : >> I see a lot of such queries in my Solr 7.6.0 logs: If you are seeing a lot of those queries, then there are other problems in your cluster you should investigate -- that's when/why LBSolrClient does this query -- to see if the server is responding. : >> *path=/select : >> params={q=*:*=false=_docid_+asc=0=javabin=2} : >> hits=287128180 status=0 QTime=7173* that is an abnormally large number of documents to have in a single shard. : >> If you want to check a zombie server, shouldn't there be a much less : >> expensive way to do a health-check instead? Probably yes -- i've opened SOLR-14298... https://issues.apache.org/jira/browse/SOLR-14298 -Hoss http://www.lucidworks.com/
Re: Why does Solr sort on _docid_ with rows=0 ?
docid is the natural order of the posting lists, so there is no sorting effort. I expect that means “don’t sort”. Also, cross-posting is probably not good. I’m replying only to solr-user. wunder Walter Underwood wun...@wunderwood.org http://observer.wunderwood.org/ (my blog) > On Feb 28, 2020, at 5:42 PM, S G wrote: > > So no one knows this then? > It seems like a good opportunity to get some performance! > > On Tue, Feb 25, 2020 at 2:01 PM S G wrote: > >> Hi, >> >> I see a lot of such queries in my Solr 7.6.0 logs: >> >> >> *path=/select >> params={q=*:*=false=_docid_+asc=0=javabin=2} >> hits=287128180 status=0 QTime=7173* >> On some searching, this is the code seems to fire the above: >> >> https://github.com/apache/lucene-solr/blob/f80e8e11672d31c6e12069d2bd12a28b92e5a336/solr/solrj/src/java/org/apache/solr/client/solrj/impl/LBSolrClient.java#L89-L101 >> >> Can someone explain why Solr is doing this? >> Note that "hits" is a very large value and is something which could be >> impacting performance? >> >> If you want to check a zombie server, shouldn't there be a much less >> expensive way to do a health-check instead? >> >> Thanks >> SG >> >> >> >>
Re: Why does Solr sort on _docid_ with rows=0 ?
So no one knows this then? It seems like a good opportunity to get some performance! On Tue, Feb 25, 2020 at 2:01 PM S G wrote: > Hi, > > I see a lot of such queries in my Solr 7.6.0 logs: > > > *path=/select > params={q=*:*=false=_docid_+asc=0=javabin=2} > hits=287128180 status=0 QTime=7173* > On some searching, this is the code seems to fire the above: > > https://github.com/apache/lucene-solr/blob/f80e8e11672d31c6e12069d2bd12a28b92e5a336/solr/solrj/src/java/org/apache/solr/client/solrj/impl/LBSolrClient.java#L89-L101 > > Can someone explain why Solr is doing this? > Note that "hits" is a very large value and is something which could be > impacting performance? > > If you want to check a zombie server, shouldn't there be a much less > expensive way to do a health-check instead? > > Thanks > SG > > > >