lucene-solr-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Shawn Heisey <>
Subject Re: Solr Cloud reclaiming disk space from deleted documents
Date Mon, 20 Apr 2015 15:25:13 GMT
On 4/20/2015 8:44 AM, Rishi Easwaran wrote:
> Yeah I noticed that. Looks like optimize won't work since on some disks we are already
pretty full.
> Any thoughts on increasing/decreasing <mergeFactor>10</mergeFactor>  or ConcurrentMergeScheduler
to make solr do merges faster.

You don't have to do an optimize to need 2x disk space.  Even normal
merging, if it happens just right, can require the same disk space as a
full optimize.  Normal Solr operation requires that you have enough
space for your index to reach at least double size on occasion.

Higher merge factors are better for indexing speed, because merging
happens less frequently.  Lower merge factors are better for query
speed, at least after the merging finishes, because merging happens more
frequently and there are fewer total segments at any given moment. 
During a merge, there is so much I/O that query speed is often
negatively affected.


View raw message