Maybe also experiment with cache=false

On Fri, Nov 17, 2023 at 2:38 PM Mikhail Khludnev <m...@apache.org> wrote:

> >   What causes this issue?
> You may try to find an answer with distrib=false and debug=timing
>
>
> On Fri, Nov 17, 2023 at 8:49 PM rajani m <rajinima...@gmail.com> wrote:
>
> > Hi again,
> >
> >   Thank you for all the pointers, they were very helpful.  After digging
> in
> > enough, I figured that it is a certain text field that matches a large
> set
> > of docs for a given query. And it is the one adding to the latency.
> > Appreciate any suggestions to optimize it.
> >
> > An example query that matches a large set of documents.
> >
> > q=cats&defType=edismax&qf=keywords description title&fl=id&rows=10 |
> Qtime
> > = 531
> >
> > The query fields are the same field type(text_en).  I tried the following
> > variants and have included their respective QTime notes.
> > 1. rows=0 | Qtime = 518
> > 2. qf=keywords | Qtime = 323 - This is the field that matches 85% of
> total
> > docs and is adding to the overall latency of  the queries
> > 3. qf=description | Qtime= 144 - This field matches 25% of total docs
> > 4. qf=title | Qtime = 17 - This field matches 5% of total docs
> >
> > It is clear that whenever a query matches a large number of docs from any
> > query fields, which is often the keywords field in this case, it has high
> > latency.  What causes this issue?  What are my options to optimize such
> > queries latency?
> >
> > Thank you,
> > Rajani
> >
> > On Thu, Nov 2, 2023 at 12:30 PM Mikhail Khludnev <m...@apache.org>
> wrote:
> >
> > > On Thu, Nov 2, 2023 at 5:01 AM rajani m <rajinima...@gmail.com> wrote:
> > >
> > > > Sorry, it took too long to get back to this one.
> > > >
> > > >  The search query "http://host:8983/solr/v9/select?&q=*&rows=10";
> > > > consistently
> > > > took ~500 ms.  With "distrib=false" all the 96 shards have QTime 0-25
> > ms.
> > > > Does this mean aggregation of results from all the shards is taking
> > ~475
> > > > ms? I also tried shards.rows=5 and it still returned in ~475 ms query
> > > time.
> > > >
> > >
> > > Giving that. Don't you have any limits for ShardHandlerFactory set in
> > > solr.xml?
> > > debugQuery=true or debug=track can produce verbose shard request
> tracing
> > > info. Perhaps it might get some clue.
> > > Full fledged approach is
> > >
> > >
> >
> https://solr.apache.org/guide/solr/latest/deployment-guide/distributed-tracing.html
> > > for sure.
> > > Might it be a problem of slow dns names resolution?
> > > Does it still slow on rows=0?
> > > --
> > > Sincerely yours
> > > Mikhail Khludnev
> > >
> >
>
>
> --
> Sincerely yours
> Mikhail Khludnev
>

Reply via email to