[CentOS] Adding RAM

Wed Dec 10 16:11:38 UTC 2008
Matt <lm7812 at gmail.com>

> The Schedular is CFQ and can be changed on the fly to whatever Block
> Device you want it. It does not matter what load the system is under.
> Changing to Deadline on his specific block device will improve the I/O
> of the system unless it really being hammered. Keep in mind these
> changes will be gone on Reboot. You can put these in rc.local to
> activate at boot time. Substitute "hda" for your device. This does not
> work on iscsi or SAN mounts.
>
> [root at blah ~]# echo 'deadline' > /sys/block/hda/queue/scheduler
> [root at blah ~]# cat /sys/block/hda/queue/scheduler
> noop anticipatory [deadline] cfq  -- Changed to Deadline.

echo 'deadline' > /sys/block/sda/queue/scheduler
-bash: /sys/block/sda/queue/scheduler: No such file or directory

 ls -l /sys/block/sda/queue/
total 0
drwxr-xr-x  2 root root    0 Dec  8 17:45 iosched
-r--r--r--  1 root root 4096 Dec 10 10:10 max_hw_sectors_kb
-rw-r--r--  1 root root 4096 Dec 10 10:10 max_sectors_kb
-rw-r--r--  1 root root 4096 Dec 10 10:10 nr_requests
-rw-r--r--  1 root root 4096 Dec 10 10:10 read_ahead_kb

No go.

Matt