Messages in this thread | | | Date | Sun, 10 Jan 2010 23:27:10 -0800 | From | "H. Peter Anvin" <> | Subject | Re: [ANNOUNCE] util-linux-ng v2.17 (stable) |
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On 01/10/2010 10:36 PM, Martin K. Petersen wrote: >>>>>> "Andreas" == Andreas Dilger <adilger@sun.com> writes: > > Andreas> I agree whole heartedly. We steer users very sharply away from > Andreas> using partitions at all, because on h/w RAID devices the > Andreas> 512-byte offset from fdisk completely kills RAID-5/6 > Andreas> performance. > > I don't have a problem aligning to 1MB (taking alignment_offset into > account) by default but there needs to be an easy override. There are > RAID arrays that internally compensate for the legacy 63 sector offset > and we'll cause misalignment if we start at 1MB on those. > > I'm heavily lobbying our storage partners to make sure they fill out the > right SCSI bits if their LUNs are not naturally aligned. But there are > obviously going to be legacy devices out there that will need manual > alignment compensation. >
Yes, but we shouldn't default to braindead mode.
-hpa
-- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.
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