On 2/16/08, Chris Mason <[EMAIL PROTECTED]> wrote: > On Friday 15 February 2008, Dongjun Shin wrote: > > Hello, > > > > When I'm running postmark on btrfs v0.12, although the system > > must be busy doing the I/O, there are some cases where the I/O is idle > > while btrfs workqueue eats up most of the CPU time. > > > > I wasn't able to reproduce this on my small ssd, but I could trigger it on my > larger sata drive. Most of the time we seem to be stuck in > btrfs_realloc_node, which is part of the defrag. > > The attached patch disables defrag in ssd mode, or you can grab the latest > from btrfs-unstable: > > http://oss.oracle.com/mercurial/mason/btrfs-unstable/archive/1cc5025e42bb.tar.gz > > I had left defrag on in ssd mode because earlier tests showed it still helped > in some read workloads. This doesn't seem to be the case anymore, but if you > see read regressions, please let me know. > > (updated no-defrag patch below) > > -chris > >
There is no more I/O stall with the latest unstable version of btrfs. Here's the postmark numbers for comparison (16k block size & ssd option). - v0.12 file size 9-15kB, num files 10k, transaction 100k => 473 TPS file size 9-15kB, num files 100k, transaction 100k => 84 TPS - latest unstable file size 9-15kB, num files 10k, transaction 100k => 483 TPS file size 9-15kB, num files 100k, transaction 100k => 129 TPS It seems that there is no read regression for postmark. Thanks, -- Dongjun _______________________________________________ Btrfs-devel mailing list [email protected] http://oss.oracle.com/mailman/listinfo/btrfs-devel
