lvm snapshots take almost 10 minutes
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
lvm2 (Ubuntu) |
Invalid
|
Undecided
|
Unassigned |
Bug Description
dmsetup, libdevmapper1.02: 1.02.08-1ubuntu10
lvm-common: 1.5.20ubuntu12
lvm2: 2.02.06-2ubuntu9
Running "lvcreate -s" to create an LVM snapshot takes about 10 minutes to complete, where it should be instantaneous. stracing lvcreate shows a lot of waiting for devices to exist (VG name is mlc2, snapshot name strace-test)
stat64(
nanosleep({0, 10000000}, NULL) = 0
stat64(
nanosleep({0, 20000000}, NULL) = 0
Then does a lot of waiting for another device:
stat64(
nanosleep({0, 10000000}, NULL) = 0
stat64(
nanosleep({0, 20000000}, NULL) = 0
etc.
In accordance with bug 38409, I currently have "KERNEL=
Side note: due to a bug in my rotation script, I found I had about 20 snapshots on a machine the other day. It then wouldn't boot, as per bug 103866 - when I removed all the snapshots, mounting the volume of which all the snapshots are taken, worked.
OK, the problem is definitely the ignore_device in udev. I deliberately didn't remove this workaround when I upgraded because I knew it always had to be put in there to fix bug 38409 (in the past). I'm not sure if there is any worth in detecting it in the postinstall or anything, but it causes bug 103866 for me as well, so it might be reasonably common.