[pve-devel] ceph firefly in pve repos

[Stefan Priebe - Profihost AG]

Am 12.09.2014 um 08:05 schrieb Dietmar Maurer:
>>> I thought that would be handled by the SSD drive internally? If there
>>> is a capicitor, the SSD can acknowledge the write immediately (write back
>> cache)?
>>
>> Some do and some do not. It depends on the firmware and the drive.
>>
>> For example the intel 520 drives ignored the command even they do NOT have a
>> capicitor.
>>
>> Intel S3700 do not ignore the command but they have a capicitor.
>>
>>> Please can you point me to your patch? (do you have a link)
>>
>> http://lists.ceph.com/pipermail/ceph-users-ceph.com/2013-
>> November/035707.html
> 
> @Stefan: and you think this is safe to use with crucial MX100 SSDs?

Oh that's a difficult question. The problem is that a lot of SSDs fail
to be consistent under power failure. Even some of thos having a capicitor.

I think you need to test it.

Currently i just ignore flushes on all devices having capicitors.

Stefan