Re: (reiserfs 3.6) sync command causes continuous writes

[dE <de.techno@gmail.com>]

On 06/11/13 14:27, tomnm wrote:
> After typing the 'sync' command all reiserfs 3.6 mounted volumes will be
> continuously written.  For example, suppose 'sdb1' contains a reiserfs
> partition.
>
> mount /dev/sdb1 /mnt/data
>
> Now type:
> cat /sys/block/sdb/stat
> and note the number of I/O's to the partition.
> wait a couple seconds, look at I/O statistics and see they don't change.
>
> Now type:
> sync
>
> Subsequently typing 'cat /sys/block/sdb/stat' every few seconds shows
> increasing I/O.
>
> This can be confirmed by trying to spin the drive down:
> hdparm -y /dev/sdb
>
> The device spins down but then immediately spins back up due to above I/O
> taking place.
>
> If you umount the drive and mount again, the continuous I/O stops, only to
> resume again as soon as you type 'sync'.
>
> This behavior started with 3.5 kernel.  All 3.4.x kernels are ok.  All 3.5.x
> and newer kernels exhibit this behavior.
>
> This does not seem to occur with ext3 or FAT.

I think I can reproduce this with 3.8.5. SysRq + S seems to do the same 
thing.

I'm judging this from the HDD LED.