Hi, I was able to reproduce it in a read-write workload, instead of the read-only workload you'd proposed.
On 2016-10-05 14:01:05 -0400, Tom Lane wrote: > Curiously, I did not see such a hang with regular SysV semaphores. > That may be just a timing thing, or it may have something to do with > POSIX semaphores being actually futexes on this platform (so that there > is state inside the process not outside it). Without yet having analyzed this deeply, could it actually be that the reason is that sem_post/wait aren't proper memory barriers? On a glance the symptoms look like values have been modified without proper locks... Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
