Bug 737200
| Summary: | unable to create a redundant logged mirror on a VG with small extents due to invalid dirty region size | |||
|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Corey Marthaler <cmarthal> | |
| Component: | lvm2 | Assignee: | Jonathan Earl Brassow <jbrassow> | |
| Status: | CLOSED ERRATA | QA Contact: | Corey Marthaler <cmarthal> | |
| Severity: | high | Docs Contact: | ||
| Priority: | high | |||
| Version: | 6.2 | CC: | agk, dwysocha, heinzm, jbrassow, mbroz, prajnoha, prockai, thornber, zkabelac | |
| Target Milestone: | rc | Keywords: | Regression, TestBlocker | |
| Target Release: | --- | |||
| Hardware: | x86_64 | |||
| OS: | Linux | |||
| Whiteboard: | ||||
| Fixed In Version: | lvm2-2.02.87-3.el6 | Doc Type: | Bug Fix | |
| Doc Text: |
Do not document.
|
Story Points: | --- | |
| Clone Of: | ||||
| : | 750882 (view as bug list) | Environment: | ||
| Last Closed: | 2011-12-06 17:03:12 UTC | Type: | --- | |
| Regression: | --- | Mount Type: | --- | |
| Documentation: | --- | CRM: | ||
| Verified Versions: | Category: | --- | ||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | ||
| Cloudforms Team: | --- | Target Upstream Version: | ||
| Embargoed: | ||||
| Bug Depends On: | ||||
| Bug Blocks: | 743047, 750882 | |||
|
Description
Corey Marthaler
2011-09-09 21:49:41 UTC
FWIW, the following dm devices are created during the failed mirror create attempt. [root@taft-01 ~]# dmsetup ls mirror_sanity-mirrored_log_on_256kextent_vg_mlog_mimage_1 (253, 4) mirror_sanity-mirrored_log_on_256kextent_vg_mlog_mimage_0 (253, 3) mirror_sanity-mirrored_log_on_256kextent_vg_mlog (253, 5) Once 737125 is eliminated, this problem remains. It is due to the fact that the kernel also imposes this restriction on mirrors:
static int _check_region_size(struct dm_target *ti, uint32_t region_size)
{
if (region_size < 2 || region_size > ti->len)
return 0;
if (!is_power_of_2(region_size))
return 0;
return 1;
}
Specifically, that the region_size be less than the length of the target. The mirror log is extremely small - normally 4MiB w/ 512kiB region_size. However, with the pe_size setting in this bug, we get a 2kiB log with 512kiB region_size. The region_size will have to be adjusted to the power of 2 that is less than the size of the log.
The other (and easier solution) is to make the log at least the size of a region. This may cause the log to be larger than it would otherwise have to be, but this will not happen when PE sizes are normal. Solution in comment 6 checked in upstream in Version 2.02.89 git commit ID: 39feace42ecc87743b42a0ff46ebc9718502774e proof of solution... [root@bp-01 ~]# !vgs vgs -o name,vg_extent_size vg VG Ext vg 1.00k [root@bp-01 ~]# lvcreate -m 1 --mirrorlog mirrored -L 20M -n lv vg Logical volume "lv" created [root@bp-01 ~]# lvs -a -o name,size vg LV LSize lv 20.00m [lv_mimage_0] 20.00m [lv_mimage_1] 20.00m [lv_mlog] 512.00k [lv_mlog_mimage_0] 512.00k [lv_mlog_mimage_1] 512.00k I no longer see this issue either on the latest scratch built rpms. ============================================================ Iteration 10 of 10 started at Thu Sep 15 11:05:25 CDT 2011 ============================================================ SCENARIO - [redundant_log_on_small_extent_vg] Create a redundant logged mirror on a VG with small extents Recreating VG with smaller (256K) extent size taft-01: vgcreate -s 256k mirror_sanity /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1 /dev/sdg1 /dev/sdh1 taft-01: lvcreate -n mirrored_log_on_256kextent_vg -L 200M -m 1 --mirrorlog mirrored mirror_sanity Deactivating mirror mirrored_log_on_256kextent_vg... and removing Restoring VG to default extent size 2.6.32-195.el6.x86_64 lvm2-2.02.87-2.1.el6 BUILT: Wed Sep 14 09:44:16 CDT 2011 lvm2-libs-2.02.87-2.1.el6 BUILT: Wed Sep 14 09:44:16 CDT 2011 lvm2-cluster-2.02.87-2.1.el6 BUILT: Wed Sep 14 09:44:16 CDT 2011 udev-147-2.38.el6 BUILT: Fri Sep 9 16:25:50 CDT 2011 device-mapper-1.02.66-2.1.el6 BUILT: Wed Sep 14 09:44:16 CDT 2011 device-mapper-libs-1.02.66-2.1.el6 BUILT: Wed Sep 14 09:44:16 CDT 2011 device-mapper-event-1.02.66-2.1.el6 BUILT: Wed Sep 14 09:44:16 CDT 2011 device-mapper-event-libs-1.02.66-2.1.el6 BUILT: Wed Sep 14 09:44:16 CDT 2011 cmirror-2.02.87-2.1.el6 BUILT: Wed Sep 14 09:44:16 CDT 2011 Fix verified in the latest official rpms. 2.6.32-198.el6.x86_64 lvm2-2.02.87-3.el6 BUILT: Wed Sep 21 09:54:55 CDT 2011 lvm2-libs-2.02.87-3.el6 BUILT: Wed Sep 21 09:54:55 CDT 2011 lvm2-cluster-2.02.87-3.el6 BUILT: Wed Sep 21 09:54:55 CDT 2011 udev-147-2.38.el6 BUILT: Fri Sep 9 16:25:50 CDT 2011 device-mapper-1.02.66-3.el6 BUILT: Wed Sep 21 09:54:55 CDT 2011 device-mapper-libs-1.02.66-3.el6 BUILT: Wed Sep 21 09:54:55 CDT 2011 device-mapper-event-1.02.66-3.el6 BUILT: Wed Sep 21 09:54:55 CDT 2011 device-mapper-event-libs-1.02.66-3.el6 BUILT: Wed Sep 21 09:54:55 CDT 2011 cmirror-2.02.87-3.el6 BUILT: Wed Sep 21 09:54:55 CDT 2011 SCENARIO - [redundant_log_on_small_extent_vg] Create a redundant logged mirror on a VG with small extents Recreating VG with smaller (256K) extent size taft-01: vgcreate -s 256k mirror_sanity /dev/sdd1 /dev/sdd2 /dev/sde1 /dev/sde2 /dev/sdf1 /dev/sdf2 /dev/sdg1 /dev/sdg2 /dev/sdh1 /dev/sdh2 taft-01: lvcreate -n mirrored_log_on_256kextent_vg -L 200M -m 1 --mirrorlog mirrored mirror_sanity Deactivating mirror mirrored_log_on_256kextent_vg... and removing Restoring VG to default extent size
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New Contents:
Do not document.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHBA-2011-1522.html |