2007/8/12, Gregory Stark <[EMAIL PROTECTED]>: > > "Gregory Stark" <[EMAIL PROTECTED]> writes: > > > >> "Tom Lane" <[EMAIL PROTECTED]> writes: > >> > >>> Gregory Stark <[EMAIL PROTECTED]> writes: > >>>> We're seeing a problem where occasionally a process appears to be > >>>> granted a > >>>> lock but miss its semaphore signal. > >>> > >>> Kernel bug maybe? What's the platform? > > I've written a synthetic test program to check for lost semaphore wakeups. I > can't seem to produce any on my machine but haven't had a chance to run it yet > on the benchmark machine that's been showing the problem. > > If I can't produce any lost wakeups with a program like this it looks more > like it might be a Postgres or GCC bug than a Linux bug. > > It would be helpful if people could run this on various architectures and > various versions of Linux (or other OSes). I've been running it with 40 > processes for an hour, but even shorter runs would be useful. It will drive > the load on your machine through the roof but doesn't cause any i/o. > > $ gcc -Wall ipctest.c -lrt > $ ./a.out 40 3600 > > > -- > Gregory Stark > EnterpriseDB http://www.enterprisedb.com > > > ---------------------------(end of broadcast)--------------------------- > TIP 3: Have you checked our extensive FAQ? > > http://www.postgresql.org/docs/faq > > > Hello [EMAIL PROTECTED] ~]$ cat /proc/sys/kernel/osrelease 2.6.22.1-41.fc7
[EMAIL PROTECTED] tmp]$ ./a.out 40 3600 running with 40 processes for 3600s [EMAIL PROTECTED] tmp]$ without any problem Regards Pavel Stehule ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org