Re: [dm-devel] [RFC] dm-thin: Heuristic early chunk copy before COW

2017-03-10 Thread Eric Wheeler
On Thu, 9 Mar 2017, Joe Thornber wrote: > Hi Eric, > > On Wed, Mar 08, 2017 at 10:17:51AM -0800, Eric Wheeler wrote: > > Hello all, > > > > For dm-thin volumes that are snapshotted often, there is a performance > > penalty for writes because of COW overhead since the modified chunk needs > >

Re: [dm-devel] [RFC] dm-thin: Heuristic early chunk copy before COW

2017-03-09 Thread Joe Thornber
Hi Eric, On Wed, Mar 08, 2017 at 10:17:51AM -0800, Eric Wheeler wrote: > Hello all, > > For dm-thin volumes that are snapshotted often, there is a performance > penalty for writes because of COW overhead since the modified chunk needs > to be copied into a freshly allocated chunk. > > What if