[dm-devel] sg_persist triggers block kernel event ???

[Christophe Varoqui]

Adding more information to this case,

also reproduced on a sles11 and with mpathpersist in place of sg_persist
(sde and sdf are paths of dm-4) :

# mpathpersist -i -k /dev/mapper/igrM2h-U2Ci-O3jL
KERNEL[1399153645.728611] change
/devices/platform/host2/session1/target2:0:0/2:0:0:2/block/sdf (block)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/platform/host2/session1/target2:0:0/2:0:0:2/block/sdf
SUBSYSTEM=block
DEVNAME=sdf
DEVTYPE=disk
SEQNUM=1811
MAJOR=8
MINOR=80

KERNEL[1399153645.729377] change
/devices/platform/host3/session2/target3:0:0/3:0:0:2/block/sde (block)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/platform/host3/session2/target3:0:0/3:0:0:2/block/sde
SUBSYSTEM=block
DEVNAME=sde
DEVTYPE=disk
SEQNUM=1812
MAJOR=8
MINOR=64

Persistent Reserve IN command failed

KERNEL[1399153645.730116] change   /devices/virtual/block/dm-4 (block)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/virtual/block/dm-4
SUBSYSTEM=block
DEVNAME=dm-4
DEVTYPE=disk
SEQNUM=1813
MAJOR=252
MINOR=4

Regards,
Christophe Varoqui
www.opensvc.com


On Sat, May 3, 2014 at 10:38 PM, Christophe Varoqui <
christophe.varoqui at opensvc.com> wrote:

> Reproduced on a fairly recent kernel :
>
> cvaroqui at clementine:~$ sudo sg_persist -k /dev/sda
>   ATA       SAMSUNG MZMTD512  DXT4
>   Peripheral device type: disk
> PR in: command not supported
>
> KERNEL[227056.238465] change
> /devices/pci0000:00/0000:00:1f.2/ata2/host1/target1:0:0/1:0:0:0/block/sda
> (block)
> ACTION=change
> DEVNAME=/dev/sda
>
> DEVPATH=/devices/pci0000:00/0000:00:1f.2/ata2/host1/target1:0:0/1:0:0:0/block/sda
> DEVTYPE=disk
> MAJOR=8
> MINOR=0
> SEQNUM=2603
> SUBSYSTEM=block
>
> cvaroqui at clementine:~$ cat /etc/lsb-release
> DISTRIB_ID=Ubuntu
> DISTRIB_RELEASE=14.04
> DISTRIB_CODENAME=trusty
> DISTRIB_DESCRIPTION="Ubuntu Trusty Tahr (development branch)"
>
> cvaroqui at clementine:~$ uname -a
> Linux clementine 3.13.0-23-generic #45-Ubuntu SMP Fri Apr 4 06:58:38 UTC
> 2014 x86_64 x86_64 x86_64 GNU/Linux
>
> Regards,
> Christophe Varoqui
> www.opensvc.com
>
>
> On Sat, May 3, 2014 at 10:12 PM, Christophe Varoqui <
> christophe.varoqui at opensvc.com> wrote:
>
>> Hi list,
>>
>> I observe this on a debian 7.5 server with a udevadm monitor running in
>> the background :
>>
>> # sg_persist -n -k /dev/sdbh
>>   PR generation=0x0, there are NO registered reservation keys
>>
>> KERNEL[448809.342461] change
>> /devices/pci0000:20/0000:20:02.2/0000:24:00.0/host0/rport-0:0-3/target0:0:1/0:0:1:12/block/sdbh
>> (block)
>> ACTION=change
>> DEVNAME=/dev/sdbh
>>
>> DEVPATH=/devices/pci0000:20/0000:20:02.2/0000:24:00.0/host0/rport-0:0-3/target0:0:1/0:0:1:12/block/sdbh
>> DEVTYPE=disk
>> MAJOR=67
>> MINOR=176
>> SEQNUM=261605
>> SUBSYSTEM=block
>>
>> Every sg_persist command, with any options, trigger events.
>>
>> On this server with more than 200 scsi devices, each receiving one
>> read-key and one read-reservation every 10 minutes, this triggers quite a
>> eavy load caused by 2 udev triggers :
>>
>> 1/ multipath -v0 $devpath
>> 2/ udisks-lvm-pv-export $pv_uuid
>>
>>
>> Question is, is it normal for a "--in" sg_persist command to trigger a
>> change event on the scsi device ? If not, what we can do about it ?
>>
>> Best regards,
>> Christophe Varoqui
>> www.opensvc.com
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/dm-devel/attachments/20140503/6f722d4b/attachment.htm>