[linux-lvm] LVM hangs

[Zdenek Kabelac]

Dne 13.11.2017 v 18:41 Gionatan Danti napsal(a):
> On 13/11/2017 16:20, Zdenek Kabelac wrote:
>>>
>>> Are you talking about RH bug 1388632?
>>> https://bugzilla.redhat.com/show_bug.cgi?id=1388632
>>>
>>> Unfortunately I can only view the google-cached version of the bugzilla
>>> page, since the bug is restricted to internal view only.
>>>
>>
>> that could be similar issue yes
>>
>>> But the google-cached version suggests that the bug is mainly hit when
>>> removing the raid-backed cache pool under IO.
>>>
>>> I my scenario, no modification (like cache removal) of the lvm setup was
>>> done when the blocks occured.
>>
>> Easiest is to check  'dmsetup status' - just to exclude if it's frozen raid 
>> case.
> 
> Hi Zdeneck,
> due to how easy is to trigger the bug, it seems a very serious problem to me. 
> As the bug report is for internal use only, can you shed some light on what 
> causes it and how to avoid?
> 
> Specifically can you confirm that, if using an "old-school" mdadm RAID device, 
> the bug does not apply?


IMHO this particular issue is probably not triggerable (at least not so 
easily) by mdadm.

lvm2 has some sort of problem compared to mdadm - it's able to 'generate' more 
device state changes per second then mdadm.

BZ is still being examined AFAIK....


Zdenek