Hi Shawn, Thanks for replying to my questions. So is it correct to assume that exposing merge metrics is not known to cause any performance degradation?
-suresh On Wed, Jan 10, 2018 at 5:40 PM, Shawn Heisey <apa...@elyograg.org> wrote: > On 1/10/2018 11:08 AM, S G wrote: > >> Last comment by Shawn on SOLR-10130 is: >> Metrics was just a theory, sounds like that's not it. >> >> It would be very interesting to know what really caused the slowdown and >> do >> we really need the config or not. >> > > That comment wasn't actually about SOLR-10130 itself.I commented on that > issue because it was semi-related to what I was looking into, so I figured > the developer who fixed it might have some insight to the question I needed > answered. > > I think that SOLR-10130 was probably handled correctly and that they did > indeed find/fix the problem. > > My comments were speculating about completely different performance issues > -- someone was seeing reduced performance upgrading from 4.x to a version > that included the fix for SOLR-10130. Because SOLR-10130 already indicated > that metrics could cause performance issues, I was wondering whether the > metrics that were added for keeping track of Jetty operation could possibly > be the source of the user's problems. The response I got indicated that it > was unlikely that the Jetty metrics were the cause. > > Performance regressions between 4.x and later versions have been noted by > many users. I think some of them were caused by changes in Lucene, and > it's possible that those who understand these issues have not yet found a > solution to fix them. > > Thanks, > Shawn > >
