Re: [PATCH 1/4] cfq: Increase default value of target_latency

2014-06-20 Thread Dave Chinner
On Fri, Jun 20, 2014 at 12:30:25PM +0100, Mel Gorman wrote: > On Fri, Jun 20, 2014 at 07:42:14AM +1000, Dave Chinner wrote: > > On Thu, Jun 19, 2014 at 02:38:44PM -0400, Jeff Moyer wrote: > > > Mel Gorman writes: > > > > > > > The existing CFQ default target_latency results in very poor performan

Re: [PATCH 1/4] cfq: Increase default value of target_latency

2014-06-20 Thread Mel Gorman
On Fri, Jun 20, 2014 at 07:42:14AM +1000, Dave Chinner wrote: > On Thu, Jun 19, 2014 at 02:38:44PM -0400, Jeff Moyer wrote: > > Mel Gorman writes: > > > > > The existing CFQ default target_latency results in very poor performance > > > for larger numbers of threads doing sequential reads. While

Re: [PATCH 1/4] cfq: Increase default value of target_latency

2014-06-20 Thread Mel Gorman
On Thu, Jun 19, 2014 at 02:38:44PM -0400, Jeff Moyer wrote: > Mel Gorman writes: > > > The existing CFQ default target_latency results in very poor performance > > for larger numbers of threads doing sequential reads. While this can be > > easily described as a tuning problem for users, it is on

Re: [PATCH 1/4] cfq: Increase default value of target_latency

2014-06-19 Thread Dave Chinner
On Thu, Jun 19, 2014 at 02:38:44PM -0400, Jeff Moyer wrote: > Mel Gorman writes: > > > The existing CFQ default target_latency results in very poor performance > > for larger numbers of threads doing sequential reads. While this can be > > easily described as a tuning problem for users, it is on

Re: [PATCH 1/4] cfq: Increase default value of target_latency

2014-06-19 Thread Jeff Moyer
Mel Gorman writes: > The existing CFQ default target_latency results in very poor performance > for larger numbers of threads doing sequential reads. While this can be > easily described as a tuning problem for users, it is one that is tricky > to detect. This patch the default on the assumption