From a65bc51cf4e5c1fe628bb182cc1a02ee83eb102d Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Tue, 9 Mar 2021 09:42:56 +0100 Subject: [PATCH] udev/dasd: change DASD udev-rule to set none scheduler MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Performance evaluation showed that using the mq-deadline scheduler for DASD devices leads to a significantly higher CPU consumption compared to using none scheduler while having the same amount of throughput. Setting none scheduler as default in the dasd udev rule. Signed-off-by: Stefan Haberland Reviewed-by: Jan Hoeppner Signed-off-by: Jan Höppner --- etc/udev/rules.d/59-dasd.rules | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/etc/udev/rules.d/59-dasd.rules b/etc/udev/rules.d/59-dasd.rules index 98fbd188..06c1bf29 100644 --- a/etc/udev/rules.d/59-dasd.rules +++ b/etc/udev/rules.d/59-dasd.rules @@ -26,10 +26,10 @@ KERNEL=="dasd*[0-9]", ENV{ID_XUID}=="?*", SYMLINK+="disk/by-id/$env{ID_BUS}-$env LABEL="dasd_symlinks_end" -# on device add set request queue scheduler to deadline +# on device add set request queue scheduler to none SUBSYSTEM!="block", GOTO="sched_end" ACTION!="change", GOTO="sched_end" -KERNEL=="dasd*[!0-9]", TEST=="queue/scheduler", ATTR{queue/scheduler}="deadline" +KERNEL=="dasd*[!0-9]", TEST=="queue/scheduler", ATTR{queue/scheduler}="none" LABEL="sched_end"