A fix was posted on this list which seems to avoid segfaults when using solr+tika. I reposted it not long ago in response to another question. Before exploring the other segfaults it would be worthwhile getting that fix. If other segfaults continue then I suggest posting the logging from Dovecot
Scheduled for 2.3.13.
I applied the fix and will observe it for the next couple of days.
Unfortunately, the issue still persists even with this patch. The log message is slightly different, though, regarding disconnection:
Dec 03 17:10:49 server.name tika[988]: INFO tika/ (application/pdf) Dec 03 17:10:49 server.name tika[988]: INFO tika/ (image/png) Dec 03 17:10:49 server.name kernel: indexer-worker[15805]: segfault at 0 ip 00007f140483db64 sp 00007ffc04fa7960 error 4 in libdovecot.so.0.0.0[7f14047f3000+db000] Dec 03 17:10:49 server.name kernel: Code: 89 f5 48 8d b8 f0 01 00 00 48 8b 52 08 4c 8b 62 48 e8 90 89 fb ff 48 8b 44 24 08 be 00 20 00 00 4c 89 ef 48 8b 80 10 01 00 00 <4c> 8b 38 e8 64 b2 fb ff 48 8b 44 24 0 Dec 03 17:10:49 server.name dovecot[988]: Dec 03 16:10:49 indexer: Error: Indexer worker disconnected, discarding 1 requests for username_stripped Dec 03 17:10:49 server.name dovecot[988]: Dec 03 16:10:49 indexer-worker(username_stripped)<1952>Ed3ek5G1BMQgARa4EL8DAKGMINRlZjjS:c+gACAkOyV+gBwAAhFs1yA: Fatal: master: service(indexer-worker): child 1952 killed
It seems that there is something else going wrong in this version.
Best, Manuel