Thanks Michael, so the use of the filepool storagepool type does not set
the O_SYNC flag (and therefor uses the cache on the raid controller) but a
normal diskpool does (and therefor doesn't use the cache)?



On Mon, Feb 11, 2013 at 11:45 AM, Michael Prix <mp AT rs6000.darktech DOT 
org>wrote:

> Hi Stefan,
>
> I assume with diskpool you mean primary pools devicetype disk.
> Create a filepool on the internal disks and measure performance against it.
> If this is as expected, the internal RAID-controller honors the
> O_SYNC-writes TSM uses for diskpools and in this case the cache of the
> RAID-controller is not used.
>
> --
> Mit freundlichen Grüßen / kind regards
>
> Michael Prix
>
>
> On 02/11/2013 11:08 AM, Stefan Folkerts wrote:
>
>> Hi Chavdar,
>>
>> If it would be the raidcontroller I would expect a CIFS copy to be slow as
>> well but it is not, a LAN based CIFS copy to the same disk the diskpool is
>> on is fast, the disk is only slow when using it with TSM.
>>
>> Regards,
>>     Stefan
>>
>>
>> On Sun, Feb 10, 2013 at 9:24 PM, Chavdar Cholev <chavdar.cholev AT gmail DOT 
>> com
>> >**wrote:
>>
>>  Hi Stefan,
>>> if it is HP server check to you have cache battery on RAID (if any) I
>>> had simmilar issue, when I do backup form disk to LTO it was ~80-90
>>> MB/s, but when nodes baked up to this disk stg it was ~8-10 MB/s even
>>> I have etherchannel 2x1Gbps ...
>>> Regards
>>> Chavdar
>>>
>>> On Sun, Feb 10, 2013 at 4:55 PM, Stefan Folkerts
>>> <stefan.folkerts AT gmail DOT com> wrote:
>>>
>>>> Hi all,
>>>>
>>>> I am running into a strange performance issue at a small TSM site.
>>>> They have an new intel based TSM server running Windows 2008 R2 running
>>>>
>>> TSM
>>>
>>>> 5.5 (don't ask) with enough CPU and memory to run the server 4 times
>>>>
>>> over.
>>>
>>>> It has 2 disks in raid 1 for the TSM log, 4 disks in raid 10 for the TSM
>>>> database and 5 disks (all 10k) for the diskpool in raid 5.
>>>> The server has 2 1Gb/s ethernet ports in a 2Gb/s LACP channel.
>>>>
>>>> A normal CIFS copy to the server raid 5 filesystem loads the interface
>>>> up
>>>> to 25%.
>>>> A TSM backup to LTO (I believe LTO4) loads the interface up to about the
>>>> same load.
>>>> However a TSM backup to the diskpool only get the load up to 5-6%.
>>>> I have tried a default dsmserv.opt and dsm.opt and 'tuned' ones.
>>>> Multiple clients or just one, MSSQL or fileserver data, nothing matters,
>>>>
>>> as
>>>
>>>> soon as I go to the diskpool the performance is gone.
>>>>
>>>> Even a local backup to 127.0.0.1 is slow to the diskpool but fast to
>>>>
>>> tape.
>>>
>>>> I did filesystem checks, recreated the filesystem, swapped the
>>>> raidcontroller (that was done before performance checks and seems a bit
>>>> silly now) but I can't find the issue.
>>>> There are no errors in Windows or TSM, everything is just fine but very
>>>> very slow.
>>>> I recreated the diskpool volumes one by one to make sure there is no
>>>>
>>> weird
>>>
>>>> fragmentation going on, that didn't change anything, even with a single
>>>> 1Gb/s connection the speed is still many times faster to tape than it is
>>>>
>>> to
>>>
>>>> the diskpool but a filecopy via CIFS to the same disk is fast.
>>>>
>>>> Has anybody ever seen this before?
>>>>
>>>> Regards,
>>>>     Stefan
>>>>
>>>