From: Jens Axboe Date: Tue, 13 Jun 2006 06:26:10 +0000 (+0200) Subject: [PATCH] Kill PF_SYNCWRITE flag X-Git-Tag: v2.6.18-rc1~1081^2~12 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b31dc66a54ad986b6b73bdc49c8efc17cbad1833;p=pandora-kernel.git [PATCH] Kill PF_SYNCWRITE flag A process flag to indicate whether we are doing sync io is incredibly ugly. It also causes performance problems when one does a lot of async io and then proceeds to sync it. Part of the io will go out as async, and the other part as sync. This causes a disconnect between the previously submitted io and the synced io. For io schedulers such as CFQ, this will cause us lost merges and suboptimal behaviour in scheduling. Remove PF_SYNCWRITE completely from the fsync/msync paths, and let the O_DIRECT path just directly indicate that the writes are sync by using WRITE_SYNC instead. Signed-off-by: Jens Axboe --- Reading git-diff-tree failed