On Fri, Dec 17, 2010 at 3:08 PM, Per Jessen <per@opensuse.org> wrote:
Arvin Schnell wrote:
On Fri, Dec 17, 2010 at 08:40:22PM +0100, Per Jessen wrote:
I've just today received a couple of Western Digital 3Tb drives, so I thought it would be worth a status report - initially on 11.3, but I'll be trying out 11.4M5 very shortly:
Platform - very plain, second-hand office desktop IBM M52 with a 2.8GHz Celeron and 2Gb memory. Drive - Western Digital WD30EZRSDTL, 5400rpm, 64Mb cache, 4096 physical sector size. SATA II.
Installation of minimal server went just fine, no problems whatsoever. Note - boot manager lilo, NOT grub.
Good to hear. Where is the partition with /boot located? Entirely below 2 TB?
Yes right at the beginning of the drive, I might try 11.4M5 with a few different partitionings.
The partitioning seems a little odd - the first partition starts at 2048s, which is 2048 512-byte sectors, so at 1048576bytes.
That is the default alignment of parted 2.2. It's a feature.
Okay. With 3Tb who cares about 1Mb ... :-) The remaining three partitions all start on a sector# that is a multiple of 8, so that seems fine.
A lot new high capacity drives actually have 4 KB physical sectors and 512 byte logical sectors. ie. The smallest internal atomic write they can actually make is 4KB. That's because they have an internal CRC for each physical sector and if any of the data changes, they have to update the CRC. So a single logical sector write will actually trigger a read-modify-write sequence of the physical sector. Therefore it is very important that filesystem pages be aligned with the underlying physical sectors. Therefore parted 2.2 was updated to interrogate the drive for the physical sector details and ensure partitions start on physical sector boundaries. Once the drive is formated the alignment is set, so you don't have to worry about it. Assuming your drive has 4KB physical sectors, you will want to ensure you only partition it on 11.3 or newer. If you did it with 11.2 or older you would see a horrible performance drop due to all the read-modify-write cycles introduced by non-alignment of pages. Greg -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org For additional commands, e-mail: opensuse-factory+help@opensuse.org