On 2014-10-21 12:40:56 +0530, Amit Kapila wrote: > While doing performance tests, I noticed a hang at higher client > counts with patch. I have tried to check call stack for few of > processes and it is as below: > > #0 0x0000008010933e54 in .semop () from /lib64/libc.so.6 > #1 0x0000000010286e48 in .PGSemaphoreLock () > #2 0x00000000102f68bc in .LWLockAcquire () > #3 0x00000000102d1ca0 in .ReadBuffer_common () > #4 0x00000000102d2ae0 in .ReadBufferExtended () > #5 0x00000000100a57d8 in ._bt_getbuf () > #6 0x00000000100a6210 in ._bt_getroot () > #7 0x00000000100aa910 in ._bt_search () > #8 0x00000000100ab494 in ._bt_first () > #9 0x00000000100a8e84 in .btgettuple () > .. > > #0 0x0000008010933e54 in .semop () from /lib64/libc.so.6 > #1 0x0000000010286e48 in .PGSemaphoreLock () > #2 0x00000000102f68bc in .LWLockAcquire () > #3 0x00000000102d1ca0 in .ReadBuffer_common () > #4 0x00000000102d2ae0 in .ReadBufferExtended () > #5 0x00000000100a57d8 in ._bt_getbuf () > #6 0x00000000100a6210 in ._bt_getroot () > #7 0x00000000100aa910 in ._bt_search () > #8 0x00000000100ab494 in ._bt_first () > ... > > The test configuration is as below: > Test env - Power - 7 (hydra) > scale_factor - 3000 > shared_buffers - 8GB > test mode - pgbench read only > > test execution - > ./pgbench -c 128 -j 128 -T 1800 -S -M prepared postgres > > I have ran it for half an hour, but it doesn't came out even after > ~2 hours. It doesn't get reproduced every time, currently I am > able to reproduce it and the m/c is in same state, if you want any > info, let me know (unfortunately binaries are in release mode, so > might not get enough information).
Hm. What commit did you apply the series ontop? I managed to reproduce a hang, but it was just something that heikki had already fixed... Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
