Hi, I''m referring to; http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=6977913 It should be in Solaris 11 Express, has anyone tried this? How this is supposed to work? Any documentation available? Yours Markus Kovero -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.opensolaris.org/pipermail/zfs-discuss/attachments/20101118/0ad67e67/attachment.html>
Hi Markus, Jeff Bonwick integrated this feature so I''ll let him describe it. In a nutshell: If you create a RAIDZ pool in OS 11 Express or if you are running at least build 129, some of the pool metadata is mirrored automatically. This is a performance feature that should increase read I/O performance, by decreasing IOPS. This feature should improve directory searches, for example. Some mirrored metadata in a RAIDZ pool in b129 is done automatically, but it doesn''t provide any additional redundancy. Redundancy is still determined by your RAIDZ configuration (raidz1, raidz2, or raidz3). This is a performance enhancement only. No property exists to disable or enable it. Its automatic, for your data lookups... Cindy On 11/18/10 03:13, Markus Kovero wrote:> Hi, I?m referring to; > > http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=6977913 > > It should be in Solaris 11 Express, has anyone tried this? How this is > supposed to work? Any documentation available? > > > > Yours > > Markus Kovero > > > ------------------------------------------------------------------------ > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Markus, Let me correct/expand this: 1. If you create a RAIDZ pool on OS 11 Express (b151a), you will have some mirrored metadata. This feature integrated into b148 and the pool version is 29. This is the part I mixed up. 2. If you have an existing RAIDZ pool and upgrade to b151a, you would need to upgrade the pool version to use this feature. In this case, newly written metadata would be mirrored. Thanks, Cindy On 11/18/10 10:15, Cindy Swearingen wrote:> Hi Markus, > > Jeff Bonwick integrated this feature so I''ll let him describe it. > > In a nutshell: > > If you create a RAIDZ pool in OS 11 Express or if you are running at > least build 129, some of the pool metadata is mirrored automatically. > This is a performance feature that should increase read I/O performance, > by decreasing IOPS. This feature should improve directory searches, > for example. > > Some mirrored metadata in a RAIDZ pool in b129 is done automatically, > but it doesn''t provide any additional redundancy. Redundancy is still > determined by your RAIDZ configuration (raidz1, raidz2, or raidz3). > This is a performance enhancement only. > > No property exists to disable or enable it. > > Its automatic, for your data lookups... > > Cindy > > On 11/18/10 03:13, Markus Kovero wrote: >> Hi, I?m referring to; >> >> http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=6977913 >> >> It should be in Solaris 11 Express, has anyone tried this? How this is >> supposed to work? Any documentation available? >> >> >> >> Yours >> >> Markus Kovero >> >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> zfs-discuss mailing list >> zfs-discuss at opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss > _______________________________________________ > zfs-discuss mailing list > zfs-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
On 18/11/2010 17:53, Cindy Swearingen wrote:> Markus, > > Let me correct/expand this: > > 1. If you create a RAIDZ pool on OS 11 Express (b151a), you will have > some mirrored metadata. This feature integrated into b148 and the pool > version is 29. This is the part I mixed up. > > 2. If you have an existing RAIDZ pool and upgrade to b151a, you would > need to upgrade the pool version to use this feature. In this case, > newly written metadata would be mirrored. >Hi, And if one creates raid-z3 pool would meta-data be a 3-way mirror as well?
> > 2. If you have an existing RAIDZ pool and upgrade to b151a, you would > > need to upgrade the pool version to use this feature. In this case, > > newly written metadata would be mirrored.> Hi,> And if one creates raid-z3 pool would meta-data be a 3-way mirror as well?Also, how are devices determined where metadata is mirrored? Yours Markus Kovero
Hi, I did a quick test (because I''m curious also). The Hardware was a 3 SATA Disk RaidZ1. What I did: 1) Create a pool with NexentaStor 3.0.4 (Pool Version 26, Raidz1 with 3 disks) 2) Disabled all caching (primarycache=none, secondarycache=none) to force media access 3) Copied and extracted a recent Linux Kernel to generate meta data intensive workload (lots of small files) 4) Copied the Linux Kernel 10 times Then I booted into SOL11 and did: 5) ran "time du -sh ." on the dataset three times and did the average 6) upgraded the pool to version 31. 7) I rewrote the data (repeated steps 3 and 4). 8) Then I measured the time again (three times average again as in step 5) I did see a ~13% improvement. Here are the numbers: Pool Version 26: ------------------- root at solaris11:/volumes/mypool# time du -sh . 3.3G . real 1m51.509s user 0m1.178s sys 0m27.115s root at solaris11:/volumes/mypool# time du -sh . 3.3G . real 1m55.953s user 0m1.128s sys 0m25.510s root at solaris11:/volumes/mypool# time du -sh . 3.3G . real 1m48.442s user 0m1.096s sys 0m24.405s = 111 Sec Pool Version 31: ---------------- root at solaris11:/volumes/mypool# time du -sh . 3.3G . real 1m30.376s user 0m1.049s sys 0m21.775s root at solaris11:/volumes/mypool# time du -sh . 3.3G . real 1m45.745s user 0m1.105s sys 0m24.739s root at solaris11:/volumes/mypool# time du -sh . 3.3G . real 1m38.199s user 0m1.093s sys 0m24.096s = 97 Sec This means 14 seconds faster, which equals to ~13% of the total 111 secs. I expect even more exciting results for wider raidz and raidz2 arrays. Regards, Robert -- This message posted from opensolaris.org