On 9/22/16 5:59 AM, Shawn Heisey wrote:
On 9/22/2016 5:46 AM, Muhammad Zahid Iqbal wrote:
Did you find any solution to slow searches? As far as I know jetty
container default configuration is bit slow for large production
environment.
This might be true for the default configuration that comes with a
completely stock jetty downloaded from eclipse.org, but the jetty
configuration that *Solr* ships with is adequate for just about any Solr
installation. The Solr configuration may require adjustment as the
query load increases, but the jetty configuration usually doesn't.
Thanks,
Shawn
It turned out to be a "sequence of performance testing sessions" in
order to locate slowness. Though I am not completely done with it, here
are my finding so far. We are using NRT configuration (warm up count to
0 for caches and NRTCachingDirectoryFactory for index directory)
1. Essentially, solr searches (particularly with edismax and relevance)
generate lot of "garbage" that makes GC activity to kick in more often.
This becomes even more when facets are included. This has huge impact on
QTimes (I have 12g heap and configured 6g to NewSize).
2. After a fresh restart (or core reload) when searches are performed,
Solr would initially "populate" mmap entries and this is adding to total
QTimes (I have made sure that index files are cached at filesystem layer
using vmtouch - https://hoytech.com/vmtouch). When run the same test
again with mmap entries populated from previous tests, it shows improved
QTimes relative to previous test.
3. Seems the populated mmap entries are flushed away after certain idle
time (not sure if it is controlled by Solr or underlying OS). This will
make subsequent searches to fetch from "disk" (even though the disk
items are cached by OS).
So, what I am gonna try next is to tune the field(s) for facets to
reduce the index size if possible. Though I am not sure, if it will have
impact but would attempt to change the "caches" even though they will be
invalidated after a softCommit (every 10 minutes in my case).
Any other tips/clues/suggestions are welcome. Thanks.
