Bug 1354650
| Summary: | raid0 needs a default stripe number | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Corey Marthaler <cmarthal> |
| Component: | lvm2 | Assignee: | Heinz Mauelshagen <heinzm> |
| lvm2 sub component: | Mirroring and RAID | QA Contact: | cluster-qe <cluster-qe> |
| Status: | CLOSED ERRATA | Docs Contact: | |
| Severity: | low | ||
| Priority: | unspecified | CC: | agk, heinzm, jbrassow, msnitzer, prajnoha, prockai, zkabelac |
| Version: | 7.3 | ||
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2016-11-04 04:15:36 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
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Description
Corey Marthaler
2016-07-11 20:47:33 UTC
When creating raid4/5/6/10 LVs without requesting stripes or providing a PV list on the command line, all PVs of the VG will be tried using for stripes. That'll either cause unexpected many stripes (e.g. 60 with 60 PVs in the VG) or fail in case the current lvm limit for maximum RAID stripes is surpassed I propose new defaults for the various raid mappings, in particular to avoid that 'stripe bomb' occuring without -i/--stripes provided: raid0: 2 stripes (i.e. 2 stripes net capacity) raid4/5/6: 3 stripes total (i.e. 2 stripes net capacity) raid6: 5 stripes (i.e. 3 stripes net capacity) raid10: 4 stripes (capacity depends on raid10 data copies, e.g. 2 data copies = net 2 stripes capacity) As a future direction, we may add config options for the number of stripes so that those can be defined in lvm.conf and/or set/overridden with command line option --config. line "raid4/5/6: 3 stripes total (i.e. 2 stripes net capacity)" in comment #2 should read "raid4/5: 3 stripes total (i.e. 2 stripes net capacity)" Upstream commit 3928c96a37941d765bf467d82502cd2aec7fd809 sets defaults as of comments #2/#4 Upstream commit 7eb79091937d01eec51fc6a034879a6fe607231d makes the previous behaviour of taking all devices to stripe across when none have been provided via -i/--stripes configurable via "activation/raid_stripe_all_devices = [0/1]" in lvm.conf(5). That option defaults to '0', hence supplying new defaults as of comments #2/#4 but provides the user with requesting the old behaviour in case his deployments rely on it. Fix verified in the latest rpms. 3.10.0-510.el7.x86_64 lvm2-2.02.166-1.el7 BUILT: Wed Sep 28 02:26:52 CDT 2016 lvm2-libs-2.02.166-1.el7 BUILT: Wed Sep 28 02:26:52 CDT 2016 lvm2-cluster-2.02.166-1.el7 BUILT: Wed Sep 28 02:26:52 CDT 2016 device-mapper-1.02.135-1.el7 BUILT: Wed Sep 28 02:26:52 CDT 2016 device-mapper-libs-1.02.135-1.el7 BUILT: Wed Sep 28 02:26:52 CDT 2016 device-mapper-event-1.02.135-1.el7 BUILT: Wed Sep 28 02:26:52 CDT 2016 device-mapper-event-libs-1.02.135-1.el7 BUILT: Wed Sep 28 02:26:52 CDT 2016 device-mapper-persistent-data-0.6.3-1.el7 BUILT: Fri Jul 22 05:29:13 CDT 2016 [root@host-116 ~]# lvcreate --type raid0 -L 100M vg Using default stripesize 64.00 KiB. Rounding size 100.00 MiB (25 extents) up to stripe boundary size 104.00 MiB (26 extents). Logical volume "lvol0" created. [root@host-116 ~]# lvcreate --type raid0_meta -L 100M vg Using default stripesize 64.00 KiB. Rounding size 100.00 MiB (25 extents) up to stripe boundary size 104.00 MiB (26 extents). Logical volume "lvol1" created. lvol0 vg rwi-a-r--- 104.00m lvol0_rimage_0(0),lvol0_rimage_1(0) [lvol0_rimage_0] vg iwi-aor--- 52.00m /dev/sda1(0) [lvol0_rimage_1] vg iwi-aor--- 52.00m /dev/sdb1(0) lvol1 vg rwi-a-r--- 104.00m lvol1_rimage_0(0),lvol1_rimage_1(0) [lvol1_rimage_0] vg iwi-aor--- 52.00m /dev/sda1(14) [lvol1_rimage_1] vg iwi-aor--- 52.00m /dev/sdb1(14) [lvol1_rmeta_0] vg ewi-aor--- 4.00m /dev/sda1(13) [lvol1_rmeta_1] vg ewi-aor--- 4.00m /dev/sdb1(13) 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. https://rhn.redhat.com/errata/RHBA-2016-1445.html |