On 06/06/13 15:35, Joshua D. Drake wrote: > > I had the distinct displeasure of staying up entirely too late with a > customer this week because they upgraded to 12.04 and immediately > experienced a huge performance regression. In the process they also > upgraded to PostgreSQL 9.1 from 8.4. There were a lot of knobs to > change/fix/modify because of this. However, nothing I did fixed the > problem. Until... I upgraded the kernel. We ran head-long into this problem the day after you posted this. We are in the process of moving from PG 8.4 on UB Server 10.0 LTS onto PG 9.2 on UB Server 12.04 LTS and encountered this very issue during the pg_upgradecluster process. A colleague mentioned this LKML thread: <http://lkml.indiana.edu/hypermail/linux/kernel/1210.1/00725.html> Seems it was fixed in 3.9.x. I'm wonder if there is any way to easily determine if the fix was back-ported to the various Ubunutu-maintained kernels for Precise? Bosco. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general