Andy Colson wrote:
So if there is very little io, or if there is way way too much, then the scheduler really doesn't matter. So there is a slim middle ground where the io is within a small percent of the HD capacity where the scheduler might make a difference?
That's basically how I see it. There seem to be people who run into workloads in the middle ground where the scheduler makes a world of difference. I've never seen one myself, and suspect that some of the reports of deadline being a big improvement just relate to some buginess in the default CFQ implementation that I just haven't encountered.
-- Greg Smith 2ndQuadrant Baltimore, MD PostgreSQL Training, Services and Support greg@xxxxxxxxxxxxxxx www.2ndQuadrant.com -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
