Live migration fails due to a guest OS whose memory load is extremely high.

Solution Verified - Updated -

Issue

  • We ran a stress test on a guest OS so that memory load on the guest OS was extremely high.  Then, we ran "virsh migrate" for the guest OS to migrate to another host under the above condition.

  • It took about 10 minutes for the command to complete.

  • The guest OS appeared to have migrated to another host, but we were unable to control it at all.
  • virt-manager works as well as the above virsh.  So, even if live migration by virt-manager appears to succeed, the guest OS can't be controlled by virt-manager (mouse operation and key input), and appears to hang up.
  • Additionally, it doesn't respond to any ping.

  • How reproducible: Reproduced 3 times in 6 tests.

  • Step to Reproduce:

    1. Set up migration environment according to "Virtualization Administration Guide (*)".
      * http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Administration_Guide/shared-storage-nfs-migration.html
      * http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Administration_Guide/sect-Virtualization-KVM_live_migration-Live_KVM_migration_with_virsh.html
    
    2. Install the following guest OS.
      OS : RHEL5.5(Intel64)
      MEM: 2048MB
    
    3. Prepare a test program for memory stress testing.
    
    3-1. Extract all files from the attached himeno.tar.gz.
      # tar zxvf himeno.tar.gz  <-- Appended file himeno.tar.gz
      himeno/
      himeno/himenoBMTxps.c
      himeno/Makefile
    
    3-2. Move to the directory himeno.
      # cd himeno
    
    3-3. Compile a test program.
      # make
      gcc -c -O3 -DMIDDLE himenoBMTxps.c
      gcc -o bmt himenoBMTxps.o -O3 -DMIDDLE
    
    3-4. Check that the test program bmt is available.
      # ll
      total 36
      -rw-r--r-- 1 root root   237 Jul 12 11:11 Makefile
      -rwxr-xr-x 1 root root 11630 Jul 13 09:49 bmt  <-- Test tool
      -rw-r--r-- 1 root root  7000 Jul 12 10:55 himenoBMTxps.c
      -rw-r--r-- 1 root root 10232 Jul 13 09:49 himenoBMTxps.o
    
    4. Run the test program bmt on the guest OS.
      # while true; do ./bmt; done
    
    5. Run the following command for live migration.
      # virsh migrate --live  qemu+ssh:///system
    
    6. Run "ping" to the guest OS from the destination host.
      # ping
    
    7. Try mouse operation and key input to the guest OS on virt-manager GUI.
    
  • Actual Results: Live migration fails due to a guest OS whose memory load is extremely high.

  • Expected Results: Live migration succeeds even if a guest OS whose memory load is extremely high.

Environment

  • Red Hat Enterprise Linux 6.0

  • x86_64

  • libvirt-0.8.1-27.el6

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase of over 48,000 articles and solutions.

Current Customers and Partners

Log in for full access

Log In
Close

Welcome! Check out the Getting Started with Red Hat page for quick tours and guides for common tasks.