Re: [PATCH 23/24] cfq-iosched: collect stats from dead cfqgs

2013-01-08 Thread Vivek Goyal
On Fri, Dec 28, 2012 at 12:35:45PM -0800, Tejun Heo wrote: > To support hierarchical stats, it's necessary to remember stats from > dead children. Add cfqg->dead_stats and make a dying cfqg transfer > its stats to the parent's dead-stats. > > The transfer happens form ->pd_offline_fn() and it is

Re: [PATCH 23/24] cfq-iosched: collect stats from dead cfqgs

2013-01-02 Thread Tejun Heo
Hey, Vivek. On Wed, Jan 02, 2013 at 11:44:15AM -0500, Vivek Goyal wrote: > > > In fact if we have a realiable way of resetting status then online/offline > > > infrastructure might not be required? I think per cpu stats will be a > > > problem though and that's why we probably require logic to onl

Re: [PATCH 23/24] cfq-iosched: collect stats from dead cfqgs

2013-01-02 Thread Vivek Goyal
On Wed, Jan 02, 2013 at 11:30:10AM -0500, Tejun Heo wrote: > Hey, Vivek. > > On Wed, Jan 02, 2013 at 11:24:15AM -0500, Vivek Goyal wrote: > > On Fri, Dec 28, 2012 at 12:35:45PM -0800, Tejun Heo wrote: > > > To support hierarchical stats, it's necessary to remember stats from > > > dead children.

Re: [PATCH 23/24] cfq-iosched: collect stats from dead cfqgs

2013-01-02 Thread Tejun Heo
Hey, Vivek. On Wed, Jan 02, 2013 at 11:24:15AM -0500, Vivek Goyal wrote: > On Fri, Dec 28, 2012 at 12:35:45PM -0800, Tejun Heo wrote: > > To support hierarchical stats, it's necessary to remember stats from > > dead children. Add cfqg->dead_stats and make a dying cfqg transfer > > its stats to th

Re: [PATCH 23/24] cfq-iosched: collect stats from dead cfqgs

2013-01-02 Thread Vivek Goyal
On Fri, Dec 28, 2012 at 12:35:45PM -0800, Tejun Heo wrote: > To support hierarchical stats, it's necessary to remember stats from > dead children. Add cfqg->dead_stats and make a dying cfqg transfer > its stats to the parent's dead-stats. Hi Tejun, Why not directly transfer stats to cfqg->stats.