Creating Disk Array - Stripe Size

Was using HP config utility to set up array and i was a lil unsure of what
stripe size I need to set. Infact what is a stripe size and how does it
correlate with the OS and SQL ..
So when i selected a RAID 5 option, a default of 64KB appeared as the stripe
size
and when i created another RAID 1+ 0 array, the default stripe size was
128KB.
Can anyone shed some light on stripe size and if these settings are optimal
? Would love to understand the internals to all of this ..
ThanksHi
SQL Server does I/O in 8 extends of 8KB (=64KB).
If the disk subsystem and the OS formatting are all 64KB, you will most
likely have the best performance.
RAID-5 is bad for transaction logs due to the sequential write nature of it.
It is best to have RAID-10 or 0+1, even for data.
There has been a lot of discussion in this group over the past 3 months
about it.
Regards
--
Mike Epprecht, Microsoft SQL Server MVP
Zurich, Switzerland
IM: mike@.epprecht.net
MVP Program: http://www.microsoft.com/mvp
Blog: http://www.msmvps.com/epprecht/
"Hassan" <fatima_ja@.hotmail.com> wrote in message
news:%23UIqMG6QFHA.2348@.tk2msftngp13.phx.gbl...
> Was using HP config utility to set up array and i was a lil unsure of what
> stripe size I need to set. Infact what is a stripe size and how does it
> correlate with the OS and SQL ..
> So when i selected a RAID 5 option, a default of 64KB appeared as the
> stripe
> size
> and when i created another RAID 1+ 0 array, the default stripe size was
> 128KB.
> Can anyone shed some light on stripe size and if these settings are
> optimal
> ? Would love to understand the internals to all of this ..
> Thanks
>|||We intend to use RAID 1 + 0 for our data and log files.. but the stripe size
it chose by default was 128KB and not 64KB. Is that a problem ?
"Mike Epprecht (SQL MVP)" <mike@.epprecht.net> wrote in message
news:OXrNnp6QFHA.576@.TK2MSFTNGP15.phx.gbl...
> Hi
> SQL Server does I/O in 8 extends of 8KB (=64KB).
> If the disk subsystem and the OS formatting are all 64KB, you will most
> likely have the best performance.
> RAID-5 is bad for transaction logs due to the sequential write nature of
it.
> It is best to have RAID-10 or 0+1, even for data.
> There has been a lot of discussion in this group over the past 3 months
> about it.
> Regards
> --
> Mike Epprecht, Microsoft SQL Server MVP
> Zurich, Switzerland
> IM: mike@.epprecht.net
> MVP Program: http://www.microsoft.com/mvp
> Blog: http://www.msmvps.com/epprecht/
> "Hassan" <fatima_ja@.hotmail.com> wrote in message
> news:%23UIqMG6QFHA.2348@.tk2msftngp13.phx.gbl...
> > Was using HP config utility to set up array and i was a lil unsure of
what
> > stripe size I need to set. Infact what is a stripe size and how does it
> > correlate with the OS and SQL ..
> >
> > So when i selected a RAID 5 option, a default of 64KB appeared as the
> > stripe
> > size
> > and when i created another RAID 1+ 0 array, the default stripe size was
> > 128KB.
> >
> > Can anyone shed some light on stripe size and if these settings are
> > optimal
> > ? Would love to understand the internals to all of this ..
> >
> > Thanks
> >
> >
>|||Unless you have an overriding reason, go with the manufacturer's default
settings. Most of the time the hardware is optimized for the default
settings or the defaults are what the hardware works best at. Either way,
don't change anything unless the hardware manufacturer suggests it. As Mike
noted, 64K is the SQL Extent allocation size so any multiple of that will
not cause a SQL performance issue.
Geoff N. Hiten
Microsoft SQL Server MVP
Senior Database Administrator
"Hassan" <fatima_ja@.hotmail.com> wrote in message
news:%23hK55V7QFHA.3288@.TK2MSFTNGP14.phx.gbl...
> We intend to use RAID 1 + 0 for our data and log files.. but the stripe
> size
> it chose by default was 128KB and not 64KB. Is that a problem ?
> "Mike Epprecht (SQL MVP)" <mike@.epprecht.net> wrote in message
> news:OXrNnp6QFHA.576@.TK2MSFTNGP15.phx.gbl...
>> Hi
>> SQL Server does I/O in 8 extends of 8KB (=64KB).
>> If the disk subsystem and the OS formatting are all 64KB, you will most
>> likely have the best performance.
>> RAID-5 is bad for transaction logs due to the sequential write nature of
> it.
>> It is best to have RAID-10 or 0+1, even for data.
>> There has been a lot of discussion in this group over the past 3 months
>> about it.
>> Regards
>> --
>> Mike Epprecht, Microsoft SQL Server MVP
>> Zurich, Switzerland
>> IM: mike@.epprecht.net
>> MVP Program: http://www.microsoft.com/mvp
>> Blog: http://www.msmvps.com/epprecht/
>> "Hassan" <fatima_ja@.hotmail.com> wrote in message
>> news:%23UIqMG6QFHA.2348@.tk2msftngp13.phx.gbl...
>> > Was using HP config utility to set up array and i was a lil unsure of
> what
>> > stripe size I need to set. Infact what is a stripe size and how does it
>> > correlate with the OS and SQL ..
>> >
>> > So when i selected a RAID 5 option, a default of 64KB appeared as the
>> > stripe
>> > size
>> > and when i created another RAID 1+ 0 array, the default stripe size was
>> > 128KB.
>> >
>> > Can anyone shed some light on stripe size and if these settings are
>> > optimal
>> > ? Would love to understand the internals to all of this ..
>> >
>> > Thanks
>> >
>> >
>>
>