Re: btrfs metadata reclaim behavior/performance characteristics

2017-05-22 Thread Liu Bo
On Sun, May 21, 2017 at 03:45:02PM +0300, Nikolay Borisov wrote: > > > On 19.05.2017 21:32, Liu Bo wrote: > > On Fri, May 19, 2017 at 12:54:59PM +0300, Nikolay Borisov wrote: > >>> From: Liu Bo > >>> > >>> Subject: [PATCH] Btrfs: skip commit transaction if we don't have enough > >>> pinned byte

Re: btrfs metadata reclaim behavior/performance characteristics

2017-05-21 Thread Nikolay Borisov
On 19.05.2017 21:32, Liu Bo wrote: > On Fri, May 19, 2017 at 12:54:59PM +0300, Nikolay Borisov wrote: >>> From: Liu Bo >>> >>> Subject: [PATCH] Btrfs: skip commit transaction if we don't have enough >>> pinned bytes >>> >>> We commit transaction in order to reclaim space from pinned bytes becau

Re: btrfs metadata reclaim behavior/performance characteristics

2017-05-19 Thread Liu Bo
On Fri, May 19, 2017 at 12:54:59PM +0300, Nikolay Borisov wrote: > > From: Liu Bo > > > > Subject: [PATCH] Btrfs: skip commit transaction if we don't have enough > > pinned bytes > > > > We commit transaction in order to reclaim space from pinned bytes because > > it could process delayed refs

Re: btrfs metadata reclaim behavior/performance characteristics

2017-05-19 Thread Nikolay Borisov
> From: Liu Bo > > Subject: [PATCH] Btrfs: skip commit transaction if we don't have enough > pinned bytes > > We commit transaction in order to reclaim space from pinned bytes because it > could process delayed refs, and in may_commit_transaction(), we check first > if pinned bytes are enough

Re: btrfs metadata reclaim behavior/performance characteristics

2017-05-18 Thread Liu Bo
On Thu, May 18, 2017 at 06:41:08PM +0300, Nikolay Borisov wrote: > > > On 18.05.2017 17:45, Liu Bo wrote: > > On Thu, May 18, 2017 at 11:40:05AM +0300, Nikolay Borisov wrote: > > > > > > > Just some random thoughts here. > > > > Hmm, not sure if this matters, but fstests now doesn't set --mi

Re: btrfs metadata reclaim behavior/performance characteristics

2017-05-18 Thread Nikolay Borisov
On 18.05.2017 17:45, Liu Bo wrote: > On Thu, May 18, 2017 at 11:40:05AM +0300, Nikolay Borisov wrote: > > Just some random thoughts here. > > Hmm, not sure if this matters, but fstests now doesn't set --mixed even if the > disk size is as small as 256mb. So are you testing a mixed btrfs or

Re: btrfs metadata reclaim behavior/performance characteristics

2017-05-18 Thread Liu Bo
On Thu, May 18, 2017 at 11:40:05AM +0300, Nikolay Borisov wrote: > Hello list, > > As a result of the perf regression discovered in [0] I also took the time to > investigate the behavior of the metadata reclaim algorithm and how it chagned > with the introduction of the ticketed reservations. My

btrfs metadata reclaim behavior/performance characteristics

2017-05-18 Thread Nikolay Borisov
Hello list, As a result of the perf regression discovered in [0] I also took the time to investigate the behavior of the metadata reclaim algorithm and how it chagned with the introduction of the ticketed reservations. My tests were performed on the following commits: Pre-ticketed => c83f8effe