On Saturday, October 3, 2015 4:36 AM, ajaykbs <ajayakumarbs@xxxxxxxxx> wrote: > version: Postgresql-9.4 > Hardware: HP DL980 (8-processor, 80 cores w/o hyper threading, 512GB RAM) > Operating system: Red Hat Enterprise Linux Server release 6.4 (Santiago) > uname -a : Linux host1 2.6.32-358.el6.x86_64 #1 SMP Tue Jan 29 11:47:41 EST > 2013 x86_64 x86_64 x86_64 GNU/Linux Single database with separate tablespace > for main-data, pg_xlog and indexes > > I have a database having 770GB size and expected to grow to 2TB within the > next year. The database was running in a 2processor HP DL560 (16 cores) and > as the transactions of the database were found increasing, we have changed > the hardware to DL980 with 8 processors and 512GB RAM. > > Problem It is observed that at some times during moderate load the CPU > usage goes up to 400% and the users are not able to complete the queries in > expected time. But the load is contributed by some system process only. The > average connections are normally 50. But when this happens the connections > will shoot up to max-connections. You might find this thread interesting: http://www.postgresql.org/message-id/flat/55783940.8080302@xxxxxxxxxx#55783940.8080302@xxxxxxxxxx The short version is that in existing production versions you can easily run in to such symptoms when you get to 8 or more CPU packages. The problem seems to be solved in the development versions of 9.5 (with changes not suitable for back-patching to a stable branch). -- Kevin Grittner EDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
