lucene-solr-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Toke Eskildsen>
Subject RE: how to debug solr performance degradation
Date Tue, 24 Feb 2015 20:34:24 GMT
Tang, Rebecca [] wrote:
[12-15 second response time instead of 0-3]
> Solr index size 183G
> Documents in index 14364201
> We just have single solr box
> It has 100G memory
> 500G Harddrive
> 16 cpus

The usual culprit is memory (if you are using spinning drive as your storage). It appears
that you have enough raw memory though. Could you check how much memory the machine has free
for disk caching? If it is a relative small amount, let's say below 50GB, then please provide
a breakdown of what the memory is used for (very large JVM heap for example).

> I want to pinpoint where the performance issue is coming from.  Could I have some suggestions/help
on how to benchmark/debug solr performance issues.

Rough checking of IOWait and CPU load is a fine starting point. If if is CPU load then you
can turn on debug in Solr admin, which should tell you where the time is spend resolving the
queries. It it is IOWait then ensure a lot of free memory for disk cache and/or improve your
storage speed (SSDs instead of spinning drives, local storage instead of remote).

- Toke Eskildsen, State and University Library, Denmark.

View raw message