I'm having two problems with Solr 4.9.1. I can't upgrade yet, because we are using a third-party plugin component that is not yet explicitly qualified for anything newer than 4.9.0. The point release upgrade seemed like a safe bet, because I know that we don't do API changes in point releases. These are transient problems, and do not seem to be affecting the index at this time.
Some background info: Ubuntu 14, Java 8u40 from the webupd8 PPA, Solr 4.9.1. It is *NOT* SolrCloud. Full rebuilds on my index involve building a new index in cores that I have designated "build" cores, then swapping those cores with "live" cores. This always worked flawlessly before I updated to Solr 4.9.1 and migrated the config to use core discovery. root@idxb4:~# cat /index/solr4/cores/sparkinc_0/core.properties name=sparkinclive dataDir=../../data/sparkinc_0 root@idxb4:~# cat /index/solr4/cores/sparkinc_1/core.properties name=sparkincbuild dataDir=../../data/sparkinc_1 The first problem: Sometimes, in a completely unpredictable manner, the new solr.xml format seems to behave like using the old format with persistent=false. When I restarted Solr yesterday, that action swapped the live cores with the build cores and I lost half my index because it swapped back to the previous build cores. Just now when I tried a restart, everything worked flawlessly and the cores did not swap. The second problem: Sometimes old index segments do not get deleted, even though they are not part of the index. Another part of the full rebuild process involves clearing the build cores before beginning the full import. The code does a deleteByQuery with *:* and then optimizes the core. Sometimes this action fails to delete the old segment files, but when I checked the core Overview in the admin UI, numDocs only reflected the newly indexed docs and deletedDocs was 0. It was actually while trying to fix/debug this second problem that I discovered the first problem. Once the rebuild finished, I wanted to see what would happen if I restarted Solr while one of my cores had 32GB of segment files that were not part of the index ... but that's when the indexes swapped. At that point, I deleted all the dataDirs on both machines (it's a distributed index), restarted Solr again, and began a full rebuild. Everything seems to be fine now. Are either of these problems anything that anyone has seen? I don't recall seeing anything come across the list before. Are there existing issues in Jira? Is there any information that I can provide which would help in narrowing down the problem? Thanks, Shawn
