Ian, Pavan, That's correct, OS is killing the process You are correct, the OS is killing the process
3766 Feb 20 14:30:14 ubuntu kernel: [23820.175868] Out of memory: Kill process 34080 (psql) score 756 or sacrifice child 3767 Feb 20 14:30:14 ubuntu kernel: [23820.175871] Killed process 34080 (psql) total-vm:1644712kB, anon-rss:820336kB, file-rss:0kB I thought, it's a memory leak, but no this is "implicitly" documented behaviour psql documentation talks about a special variable FETCH_COUNT -- FETCH_COUNT If this variable is set to an integer value > 0, the results of SELECT queries are fetched and displayed in groups of that many rows, rather than the default behavior of collecting the entire result set before display. Therefore only a limited amount of memory is used, regardless of the size of the result set. Settings of 100 to 1000 are commonly used when enabling this feature. Keep in mind that when using this feature, a query might fail after having already displayed some rows. -- If I set some positive value for this variable, psql runs smoothly with any size of data. But unset that variable, and it gets killed. But it's nowhere written explicitly that psql can run out of memory while collecting the result set. Either the documentation or the behaviour should be modified. On Thu, Feb 20, 2014 at 2:35 PM, Pavan Deolasee <pavan.deola...@gmail.com>wrote: > > > > On Thu, Feb 20, 2014 at 2:32 PM, Ashutosh Bapat < > ashutosh.ba...@enterprisedb.com> wrote: > >> >> >> May be each setup has it's own breaking point. So trying with larger >> number might reproduce the issue. >> >> I tried to debug it with gdb, but all it showed me was that psql received >> a SIGKILL signal. I am not sure why. >> >> > Is the psql process running out of memory ? AFAIK OOM killer sends > SIGKILL. > > Thanks, > Pavan > > -- > Pavan Deolasee > http://www.linkedin.com/in/pavandeolasee > > -- Best Wishes, Ashutosh Bapat EnterpriseDB Corporation The Postgres Database Company
