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Description of problem: Version-Release number of selected component (if applicable): How reproducible: 95% of the time Steps to Reproduce: Create many raids with maxrecoveryrate of, say, 512. Then wait a bit while the sync goes under way. Change the recovery rates of some LVs, and the sync percentage will often drop below the value before the change. Actual results: [root@virt-008 ~]# lvchange raid/lvol3 --maxrecoveryrate 2048 Logical volume "lvol3" changed. [root@virt-008 ~]# lvs LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert lvol0 raid rwi-a-r--- 1.00g 8.59 lvol1 raid rwi-a-r--- 1.00g 8.59 lvol2 raid rwi-a-r--- 1.00g 8.59 lvol3 raid rwi-a-r--- 1.00g 8.98 lvol4 raid rwi-a-r--- 1.00g 8.59 [root@virt-008 ~]# lvchange raid/lvol1 --maxrecoveryrate 2048 Logical volume "lvol1" changed. [root@virt-008 ~]# lvs LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert lvol0 raid rwi-a-r--- 1.00g 9.38 lvol1 raid rwi-a-r--- 1.00g 6.25 lvol2 raid rwi-a-r--- 1.00g 9.38 lvol3 raid rwi-a-r--- 1.00g 10.94 lvol4 raid rwi-a-r--- 1.00g 8.98 The sync percentage dropped for lvol1 from 8.59 to 6.25. On lower percentages (up to 5) it drops to 0. Expected results: That the percentage stays the same (or higher) after the lvchange since the recovery rate setting should only speed up or slow down the process, not reverse it (if I understood it corrrectly). Tested with: lvm2-2.02.100-6.el6.x86_64 This behavior was first seen in verification of Bug 969171 (https://bugzilla.redhat.com/show_bug.cgi?id=969171#c9)
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Does the recovery rate have to be changed in a particular direction? My script is currently increasing the rate, but never decreasing. I'll attach the script I'm using.
Created attachment 881466 [details] Test I'm using to verify reported percentages do not drop. My test currently only increases recovery rate. It also assumes a VG name of 'vg'.
(In reply to Jonathan Earl Brassow from comment #5) > Created attachment 881466 [details] > Test I'm using to verify reported percentages do not drop. > > My test currently only increases recovery rate. It also assumes a VG name > of 'vg'. If you want this test to work well, you will probably have to: s/ rate=$((${a[1]} + 100)) / rate=$((10#${a[1]} + 100)) / Otherwise, some of the percent numbers will be improperly converted to octal.
I was not increasing or decreasing. I was actually sending the same number to the change command, as stated in the opening comment. However, I'll test it again with the newest build with increasing and decreasing and see what hapens.
I've tested again and by creating with a rate of 512 and changing to a rate of 2048, like in the opening comment. I still cannot reproduce.
Ok, I will re-test it today again with the newest LVM build and post back the results. Maybe it is no longer happening.
I cannot seem to reproduce this anymore. So whatever has changed in the meantime, this percentage remains the same or grows faster, as would be expected with the increase of the recovery rate. I suppose that this bug can now be closed as such, and if I run into it again in the future, I will open a new one (or re-open this one..)