From: Chris Mason Date: Wed, 24 Sep 2008 18:51:30 +0000 (-0400) Subject: Btrfs: Raise thresholds for metadata writeback X-Git-Tag: v2.6.29-rc1~27^2~9^2~55^2~56^2~24 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=24ab9cd85c11bccacbd0cce7f8e1aebd4930404c;p=pandora-kernel.git Btrfs: Raise thresholds for metadata writeback Btrfs metadata writeback is fairly expensive. Once a tree block is written it must be cowed before it can be changed again. The btree writepages code has a threshold based on a count of dirty btree bytes which is updated as IO is sent out. This changes btree_writepages to skip the writeout if there are less than 32MB of dirty bytes from the btrees, improving performance across many workloads. Signed-off-by: Chris Mason --- Reading git-diff-tree failed