Re: Recent drive errors

[Weedy <weedy2887@gmail.com>]

On Thu, May 21, 2015 at 3:58 AM, Mikael Abrahamsson <swmike@swm.pp.se> wrote:
> On Tue, 19 May 2015, Thomas Fjellstrom wrote:
>
>> How many UREs are considered "ok"? Tens, hundreds, thousands, tens of
>> thousands?
>
>
> I will replace any drive that have developed UNC sectors a few times, so I'd
> say "less than 10".
>
> +1 on the "set kernel timeout to more than 120 seconds". I have this in
> /etc/rc.local:
>
> for x in /sys/block/sd[a-z] ; do
>         echo 180  > $x/device/timeout
> done
>
> echo 4096 > /sys/block/md0/md/stripe_cache_size

#!/bin/sh

if [ -e /proc/sys/dev/raid/speed_limit_min ]; then
    echo $((1024*4)) > /proc/sys/dev/raid/speed_limit_min 2> /dev/null
    echo $((1024*24)) > /proc/sys/dev/raid/speed_limit_max 2> /dev/null
fi
if [ -e /dev/md0 -o -d /dev/md ]; then
    for md in /dev/md*; do
        echo $((1024*4)) > /sys/block/${md#/dev/}/md/stripe_cache_size
        blockdev --setra $((1024*4)) /dev/${md#/dev/}
    done
    for disk in /sys/block/sd*; do
        echo 45 > $disk/device/timeout
        smartctl -l scterc,70,70 /dev/${disk#/sys/block/}
    done
fi
for disk in /sys/block/sd*; do
    echo  cfq     > $disk/queue/scheduler
    echo  768    > $disk/queue/read_ahead_kb
    echo  256    > $disk/queue/nr_requests
    echo    8    2>/dev/null    > $disk/device/queue_depth
done