Thanks for the tip. We are using RHEL 6.9 and definitely up to date on glibc (2.12-1.209.el6_9.2). We also have the same versions on a very similar system with no segfault.
My colleague got a better backtrace that shows another extension Core was generated by `postgres: batch_user_account''. Program terminated with signal 11, Segmentation fault. #0 0x000000386712868a in __strcmp_sse42 () from /lib64/libc.so.6 Missing separate debuginfos, use: debuginfo-install postgresql96-server-9.6.5-1PGDG.rhel6.x86_64 (gdb) bt #0 0x000000386712868a in __strcmp_sse42 () from /lib64/libc.so.6 #1 0x00007fa3f0c7074c in get_query_string (pstate=<value optimized out>, query=<value optimized out>, jumblequery=<value optimized out>) at pg_hint_plan.c:1882 #2 0x00007fa3f0c70a5d in pg_hint_plan_post_parse_analyze (pstate=0x25324b8, query=0x25325e8) at pg_hint_plan.c:2875 #3 0x00000000005203bc in parse_analyze () #4 0x00000000006df933 in pg_analyze_and_rewrite () #5 0x00000000007c6f6b in ?? () #6 0x00000000007c6ff0 in CachedPlanGetTargetList () #7 0x00000000006e173a in PostgresMain () #8 0x00000000006812f5 in PostmasterMain () #9 0x0000000000609278 in main (). We aren’t sure if this indicates that pg_hint_plan is causing the segfault or if it happened to be doing something when the segfault occurred. We aren’t actually using pg_hint_plan hints in this system so we’re not sure how all this relates to segfault when another process does a ‘grant usage on schema abc to user xyz;’ unrelated to the account segfaulting. Short of better ideas, we will pull the pg_hint_plan extension and see if that removes the problem. -Blair From: Peter Geoghegan <p...@bowt.ie> Date: Saturday, March 24, 2018 at 4:18 PM To: Blair Boadway <bboad...@abebooks.com> Cc: "pgsql-gene...@postgresql.org" <pgsql-gene...@postgresql.org> Subject: Re: Troubleshooting a segfault and instance crash On Thu, Mar 8, 2018 at 9:40 AM, Blair Boadway <bboad...@abebooks.com<mailto:bboad...@abebooks.com>> wrote: Mar 7 14:46:35 pgprod2 kernel:postgres[29351]: segfault at 0 ip 000000302f32868a sp 00007ffcf1547498 error 4 in libc-2.12.so[302f200000+18a000] Mar 7 14:46:35 pgprod2 POSTGRES[21262]: [5] user=,db=,app=client= LOG: server process (PID 29351) was terminated by signal 11: Segmentation fault It crashes the database, though it starts again on its own without any apparent issues. This has happened 3 times in 2 months and each time the segfault error and memory address is the same. We had a recent report of a segfault on a Redhat compatible system, that seemed like it might originate from within its glibc [1]. Although all the versions there didn't match what you have, it's worth considering as a possibility. Maybe you can't install debuginfo packages because you don't yet have the necessary debuginfo repos set up. Just a guess. That is sometimes a required extra step. [1] https://postgr.es/m/7369.1520528...@sss.pgh.pa.us -- Peter Geoghegan
