Messages in this thread | | | Date | Sun, 28 Feb 2010 15:03:00 -0500 (EST) | From | Justin Piszcz <> | Subject | Re: mdadm software raid + ext4, capped at ~350MiB/s limitation/bug? |
| |
On Sun, 28 Feb 2010, Bill Davidsen wrote:
> Justin Piszcz wrote: >> >> >> On Sun, 28 Feb 2010, Mike Snitzer wrote: >> >>> On Sun, Feb 28, 2010 at 4:45 AM, Justin Piszcz <jpiszcz@lucidpixels.com> >>> wrote: >> >> [ .. ] >> >>> >>> How did you format the ext3 and ext4 filesystems? >>> >>> Did you use mkfs.ext[34] -E stride and stripe-width accordingly? >>> AFAIK even older versions of mkfs.xfs will probe for this info but >>> older mkfs.ext[34] won't (though new versions of mkfs.ext[34] will, >>> using the Linux "topology" info). >> >> Yes and it did not make any difference: >> http://lkml.org/lkml/2010/2/27/77 >> >> Incase anyone else wants to try too, you can calculate by hand, or if you >> are in a hurry, I found this useful: >> http://busybox.net/~aldot/mkfs_stride.html >> >> I believe there is something fundamentally wrong with ext4 when performing >> large sequential I/O when writing, esp. after Ted's comments. >> >> Justin. >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-raid" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > I'm going to have to do some testing now, I just tested ext4 against the raw > speed of the device (single device test) and they were quite close to > identical. I'm going to order one more drive to bring my test setup up to > five devices, and do some testing on how it behaves. > > More later.
Thanks, let me know how it goes, I see the same thing, on a single hard drive, there is little difference between EXT4 and XFS: http://permalink.gmane.org/gmane.linux.kernel/955357
However, when multiple disks are involved, it is a different story.
Justin.
| |