Bug 210395

Summary: pvmove causes the machine to hang when moving /
Product: Red Hat Enterprise Linux 4 Reporter: Forrest Taylor <ftaylor>
Component: lvm2Assignee: Milan Broz <mbroz>
Status: CLOSED CURRENTRELEASE QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: 4.4CC: agk, dwysocha, mbroz, prockai, pvrabec
Target Milestone: ---   
Target Release: ---   
Hardware: i686   
OS: Linux   
Whiteboard:
Fixed In Version: RHEL4.5 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2007-05-16 14:24:59 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:
Attachments:
Description Flags
An strace of pvmove in init 1
none
Strace output from pvmove in rescue mode none

Description Forrest Taylor 2006-10-11 20:27:06 UTC 
Description of problem:
pvmove causes the machine to hang when moving the data from the logical volume
that contains the / file system.

Disk layout before:
/dev/hda1   *           1          13      104391   83  Linux
/dev/hda2              14         778     6144862+  8e  Linux LVM
/dev/hda3             779         843      522112+  82  Linux swap

Disk layout after:
/dev/hda1   *           1          13      104391   83  Linux
/dev/hda2              14         778     6144862+  8e  Linux LVM
/dev/hda3             779         843      522112+  82  Linux swap
/dev/hda4             844        2434    12779707+   5  Extended
/dev/hda5             844        1695     6843658+  83  Linux LVM


lvdisplay
--
  --- Logical volume ---
  LV Name                /dev/vol0/root
  VG Name                vol0
  LV UUID                Aip5j3-m4Kg-svv7-83OX-XCNe-cdvX-G6zCq8
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                4.91 GB
  Current LE             157
  Segments               1
  Allocation             inherit
  Read ahead sectors     0
  Block device           253:1

  --- Logical volume ---
  LV Name                /dev/vol0/home
  VG Name                vol0
  LV UUID                Y61XDG-sdtE-hivY-N6bE-HTAF-muzN-nWTMmB
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                512.00 MB
  Current LE             16
  Segments               1
  Allocation             inherit
  Read ahead sectors     0
  Block device           253:2


Once I create the new partition, and add it to the volume group, I run:
pvmove -v /dev/hda2 /dev/hda5

Eventually the machine will stop responding and I'll hard reboot it.  The pvmove
will continue as will hang the machine and I have to hard reboot again.  This
normally occurs several times before it completes successfully.


Version-Release number of selected component (if applicable):
RHEL4 with all updates (4.4)
lvm2-2.02.06-6.0.RHEL4
kernel-2.6.9-42.0.3.EL
device-mapper-1.02.07-4.0.RHEL4


How reproducible:
Always the first time.  I hard reboot and the machine continues the pvmove.
Normally several hard reboots are required for the pvmove to complete.
Comment 1 Forrest Taylor 2006-10-11 20:28:28 UTC 
Created attachment 138275 [details]
An strace of pvmove in init 1

This contains the strace of pvmove when running from single user mode.
Comment 2 Forrest Taylor 2006-10-11 20:30:46 UTC 
Created attachment 138276 [details]
Strace output from pvmove in rescue mode

This is the strace output from the pvmove done in rescue mode.	In this
instance, the / file system was mounted read-only so that I had access to
strace.  The hangs also occured when the filesystem was not mounted at all.
Comment 3 Forrest Taylor 2007-05-11 17:11:36 UTC 
I just tried moving / from a regular partition to a RAID1 device on x86_64, and
it worked fine (just before RHEL4.5).  I will also attempt to verify this on RHEL5.
Comment 4 Milan Broz 2007-05-16 14:24:59 UTC 
ok, I am closing this bug. Please reopen it (or open new one for RHEL5) if an
another issue arise.