From: Vivek Goyal Date: Thu, 3 Dec 2009 17:59:56 +0000 (-0500) Subject: blkio: Wait on sync-noidle queue even if rq_noidle = 1 X-Git-Tag: v2.6.33-rc1~379^2~13 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c04645e592d4dd60c58def40c913699d4c806727;p=pandora-kernel.git blkio: Wait on sync-noidle queue even if rq_noidle = 1 o rq_noidle() is supposed to tell cfq that do not expect a request after this one, hence don't idle. But this does not seem to work very well. For example for direct random readers, rq_noidle = 1 but there is next request coming after this. Not idling, leads to a group not getting its share even if group_isolation=1. o The right solution for this issue is to scan the higher layers and set right flag (WRITE_SYNC or WRITE_ODIRECT). For the time being, this single line fix helps. This should not have any significant impact when we are not using cgroups. I will later figure out IO paths in higher layer and fix it. Signed-off-by: Vivek Goyal Signed-off-by: Jens Axboe --- Reading git-diff-tree failed