On Tue, Oct 12, 2021 at 1:07 AM Li Feng <fengli@xxxxxxxxxx> wrote: > > Xiao Ni <xni@xxxxxxxxxx> 于2021年10月12日周二 下午2:58写道: > > > > On Mon, Oct 11, 2021 at 5:42 PM Li Feng <fengli@xxxxxxxxxx> wrote: > > > > > > Xiao Ni <xni@xxxxxxxxxx> 于2021年10月11日周一 下午3:49写道: > > > > > > > > Hi all > > > > > > > > Now the per device sysfs interface file state can change failfast. Do > > > > we need a new file for failfast? > > > > > > > > I did a test. The steps are: > > > > > > > > mdadm -CR /dev/md0 -l1 -n2 /dev/sdb /dev/sdc --assume-clean > > > > cd /sys/block/md0/md/dev-sdb > > > > echo failfast > state > > > > cat state > > > > in_sync,failfast > > > > > > This works, will it be persisted to disk? > > > > > > > mdadm --detail /dev/md0 can show the failfast information. So it > > should be written in superblock. > > But I don't find how md does this. I'm looking at this. > > > Yes, I have tested that it has been persisted, but don't understand who does it. I think this is not guaranteed to be persistent: [root@eth50-1 ~]# cat /sys/block/md127/md/rd1/state in_sync,failfast [root@eth50-1 ~]# echo -failfast > /sys/block/md127/md/rd1/state [root@eth50-1 ~]# cat /sys/block/md127/md/rd1/state in_sync [root@eth50-1 ~]# mdadm --stop /dev/md* mdadm: /dev/md does not appear to be an md device mdadm: stopped /dev/md127 [root@eth50-1 ~]# mdadm -As mdadm: /dev/md/0_0 has been started with 4 drives. [root@eth50-1 ~]# cat /sys/block/md127/md/rd1/state in_sync,failfast How about we fix state_store to make sure it is always persistent? Thanks, Song