Hi,
Thanks again to the people that lost some time with this.
Considering some opinions and experience, I end up choosing 3 Raidsets
with 5 disks on each MA8000 and spliting each Raidset in smaller
partitions, delivering to each system all the partitions belonging to
each Raidset, I mean since I have 6 servers, I'll have 1 Raidset (with
partitions) for each server.
One reason for not create a single AdvFS domain with some filesets from
a whole Raidset, like sugested by Eskil Swahn, is some really bad
experiences recovering AdvFS structure through "salvage". I don't know
why but this happens and using salvage to recover ~160 GB... can you
imagine?
Another issue that I need to check is the possibility to use or not the
SAN snapshot feature with partitioned raidsets, as noted by Alan Davis.
Thanks also to alan_at_nabeth.cxo.dec.com for the considerations about the
subtle performance difference between single raidsets and partitioned
raidsets.
Wander
============================================================
Wanderley Mendes wrote:
> Hi,
>
> Thanks for all.
> Due to diversity of applications that this servers will be used for,
> and the hungry for more available space, we'll be using RAID 3/5.
> Basically 70% of this space will be used for user accounts and some
> to serve small applications. I've being used HS, RAIDS and Clusters
> for a long time and a doubt that I have since begining is about
> performance of RAID 3/5 Partitioning. So, the basic question would be
> - Not considering space lost for parity, don't I notice a poor
> performance on units driven by RAID Partitioning instead of a single
> unit of a whole RAID ?
>
> Thanks:
> Tom Webster and info about SANTK.
> Edward Murphy
> John Tan
> Jim Jones
> Don Rye
> and Alan for depth considerations.
>
>
> Wander
>
> ======
> =======================================================================================
>
> Wanderley Mendes wrote:
>
>> Hi,
>>
>> We're going to configure a SAN with 6 Servers, 2 x MA8000 with 16 x
>> 36.4 GB disks each and 2 x 8-ports Fiber Switch.
>> While trying to setup the best trade-off between loosing disks due
>> to distributed parity of RAID 3/5 and performance, I have at least
>> the following two options:
>>
>> 4 x RAID 3/5 of 5 Disks
>> 2 x RAID 3/5 of 6 Disks
>> 8 RAID Partitions for each Raidset
>> 48 Units,
>> 1 complete Raidset with 8 units for each server
>> Lost: 6 x 36.4 GB
>>
>> Or
>>
>> 4 x RAID 3/5 of 8 Disks
>> 8 RAID Partitions for each Raidset
>> 32 Units, 5 units/server
>> 2 servers with 6 units
>> Lost: 4 x 36.4 GB
>>
>> In terms of performance, does anyone see a good reason to choose the
>> first option ?
>>
>> Thanks
>>
>>
>> Wander
>>
>> --
>> ----------------------=======----------------------
>> Wanderley O. Mendes
>> Software Specialist wander_at_cptec.inpe.br
>> Phone: +55-12-560-8432 Fax: +55-12-560-8435
>> INPE/CPTEC - Cachoeira Paulista - Sao Paulo - Brazil
>> ----------------------=======----------------------
>>
>>
>
> --
> ----------------------=======----------------------
> Wanderley O. Mendes
> Software Specialist wander_at_cptec.inpe.br
> Phone: +55-12-560-8432 Fax: +55-12-560-8435
> INPE/CPTEC - Cachoeira Paulista - Sao Paulo - Brazil
> ----------------------=======----------------------
>
>
--
----------------------=======----------------------
Wanderley O. Mendes
Software Specialist wander_at_cptec.inpe.br
Phone: +55-12-560-8432 Fax: +55-12-560-8435
INPE/CPTEC - Cachoeira Paulista - Sao Paulo - Brazil
----------------------=======----------------------
Received on Wed Mar 14 2001 - 13:00:50 NZDT