Robin Hill wrote:
On Wed Dec 19, 2007 at 09:50:16AM -0500, Justin Piszcz wrote:
The (up to) 30% percent figure is mentioned here:
http://insights.oetiker.ch/linux/raidoptimization.html
That looks to be referring to partitioning a RAID device - this'll only
apply to hardware RAID or
On Sun, 23 Dec 2007 08:26:55 -0600, Jon Nelson
[EMAIL PROTECTED] said:
I've found in some tests that raid10,f2 gives me the best I/O
of any raid5 or raid10 format.
Mostly, depending on type of workload. Anyhow in general most
forms of RAID10 are cool, and handle disk losses better and so
on.
On Wed, 19 Dec 2007 07:28:20 +1100, Neil Brown
[EMAIL PROTECTED] said:
[ ... what to do with 48 drive Sun Thumpers ... ]
neilb I wouldn't create a raid5 or raid6 on all 48 devices.
neilb RAID5 only survives a single device failure and with that
neilb many devices, the chance of a second
Richard Scobie wrote:
Jon Nelson wrote:
My own tests on identical hardware (same mobo, disks, partitions,
everything) and same software, with the only difference being how
mdadm is invoked (the only changes here being level and possibly
layout) show that raid0 is about 15% faster on reads than
Peter Grandi wrote:
On Wed, 19 Dec 2007 07:28:20 +1100, Neil Brown
[EMAIL PROTECTED] said:
[ ... what to do with 48 drive Sun Thumpers ... ]
neilb I wouldn't create a raid5 or raid6 on all 48 devices.
neilb RAID5 only survives a single device failure and with that
neilb many devices,
On Tue, 25 Dec 2007 19:08:15 +,
[EMAIL PROTECTED] (Peter Grandi) said:
[ ... ]
It's the raid10,f2 *read* performance in degraded mode that is
strange - I get almost exactly 50% of the non-degraded mode
read performance. Why is that?
[ ... ] the mirror blocks have to be read from the
On Fri, 14 Dec 2007 17:26:08 +1100 NeilBrown [EMAIL PROTECTED] wrote:
+ if (strncmp(buf, external:, 9) == 0) {
+ int namelen = len-9;
+ if (namelen = sizeof(mddev-metadata_type))
+ namelen = sizeof(mddev-metadata_type)-1;
+
On Fri, 14 Dec 2007 17:26:28 +1100 NeilBrown [EMAIL PROTECTED] wrote:
+ mddev_unlock(rdev-mddev);
+ ITERATE_MDDEV(mddev, tmp) {
+ mdk_rdev_t *rdev2;
+
+ mddev_lock(mddev);
+ ITERATE_RDEV(mddev, rdev2, tmp2)
