thats what I thought then, just the partition needs to be aligned to the cylinder of the drive. And for LVM, I think this would just mean the PV, i'm not sure the the LV would be offset differently to cause any problem.
On Tue, Aug 24, 2010 at 5:34 AM, Kirby Zhou <[email protected]> wrote: > High level application may consider the stripe size of the underlying > device. > For example, a allocation pool should not let its allocation unit across the > stripe size boundary. > > If partition is not aligned with stripe size, the application would be > confused. > > Regards, > Kirby Zhou > from SOHU-RD +86-10-6272-8261 > > > -----Original Message----- > From: [email protected] [mailto:[email protected]] > On Behalf Of solarflow99 > Sent: Tuesday, August 24, 2010 6:21 PM > To: Red Hat Enterprise Linux 5 (Tikanga) discussion mailing-list > Subject: Re: [rhelv5-list] How can I align the boundary of partition / LVM / > FS within the kickstart script? > > but if the partition is aligned properly with the sector, then > shouldn't it work well? for example, if the stripe size is 16k and > the sector size is 4k, it is always a multiple that divides evenly, I > think this would hold true for both hardware and software raid. > > > > On Tue, Aug 24, 2010 at 2:41 AM, Kirby Zhou <[email protected]> wrote: >> solarflow99, >> >> Stripe size is always larger than sector size. For example, a classical > RAID >> adapter such as DELL Perc6/I should have a stripe size from 16kb to 256kb. >> >> So, if a partition is not aligned with stripe size, a significant >> performance regression of aligned IO should be detected. For example, XFS > is >> sensitive of stripe size, you can do man 'mkfs.xfs', then find "sunit" and >> "swidth" for additional information. >> >> Regards, >> Kirby Zhou >> from SOHU-RD +86-10-6272-8261 >> >> >> -----Original Message----- >> From: [email protected] > [mailto:[email protected]] >> On Behalf Of solarflow99 >> Sent: Tuesday, August 24, 2010 1:08 AM >> To: Red Hat Enterprise Linux 5 (Tikanga) discussion mailing-list >> Subject: Re: [rhelv5-list] How can I align the boundary of partition / LVM > / >> FS within the kickstart script? >> >> On Sat, Aug 21, 2010 at 9:21 PM, Kirby Zhou <[email protected]> wrote: >>> How can I align the boundary of partition / LVM / FS within the kickstart >>> script? >>> >>> There are 3 case which we need align with: >>> >>> 1. The new 4k sector-size hard disk. >>> 2. The strip size of a RAID array. >>> 3. The block size of SSD erasing. >> >> Are you sure about #2? If the partition is aligned with the drive's >> sector size, then the raid stripe size would already be aligned right? >> >> P.S. It's also interesting to mention that anaconda sets a different >> stripe size depending on how big the drive/partition is. I think >> thats hard coded in too. >> >> _______________________________________________ >> rhelv5-list mailing list >> [email protected] >> https://www.redhat.com/mailman/listinfo/rhelv5-list >> >> >> _______________________________________________ >> rhelv5-list mailing list >> [email protected] >> https://www.redhat.com/mailman/listinfo/rhelv5-list >> > > _______________________________________________ > rhelv5-list mailing list > [email protected] > https://www.redhat.com/mailman/listinfo/rhelv5-list > > > _______________________________________________ > rhelv5-list mailing list > [email protected] > https://www.redhat.com/mailman/listinfo/rhelv5-list > _______________________________________________ rhelv5-list mailing list [email protected] https://www.redhat.com/mailman/listinfo/rhelv5-list
