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  • 1.  Two VMs on same host very slow

    Posted Jan 08, 2013 05:43 PM

    I have seven hosts with ESXi 5.0 and two storage. When two vms are on the same host, the performance is much poor "in vms with Windows Server 2008 R2."



  • 2.  RE: Two VMs on same host very slow

    Posted Jan 08, 2013 06:57 PM

    Hello and welcome to the communities.

    How are the Windows 2008 R2 VMs configured? Are they on the same storage system? What are the workloads of these two systems?



  • 3.  RE: Two VMs on same host very slow

    Posted Jan 08, 2013 08:03 PM

    Hello Brian! Thanks for your response.

    For example, one of my customer have two VMs:

         VM1 -> Windows Server 2008 R2 (Only two users are conected)

         VM2 -> Linux Centos 5.7 with OpenVPN)

    Both VMs are stored in the same datastore, host and VLAN. But we have changed one of the vms to another host, the performance stay better.



  • 4.  RE: Two VMs on same host very slow

    Posted Jan 08, 2013 08:07 PM

    How many vCPUs and how much memory are on these two VMs - and how much processing and RAM are on the hosts?



  • 5.  RE: Two VMs on same host very slow

    Posted Jan 09, 2013 02:05 PM

    The RAM and Proc required by these two VMs is very low. The problem occurs only when these two VMs are in the same host.

    When we separate these two VMs (separated hosts only), the performance is very better.
    Host Summary Print Screen:


  • 6.  RE: Two VMs on same host very slow

    Posted Jan 09, 2013 02:29 PM

    please check the

    CPU ready value, balooning, vmkernel swap usage, disk latency... that is Device leteny, kernel latency etc.... from the esxtop.

    This will help to find the root cause...

    http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1008360

    http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2001003



  • 7.  RE: Two VMs on same host very slow

    Posted Jan 08, 2013 08:07 PM

    Hi

    Check the virtual machine tab from your host and see how much work load do your vm(s) have. and in summry tab check how much your ESXi server have resources availabe and tell me here. if possible take a screen shot.

    what is your storage type?



  • 8.  RE: Two VMs on same host very slow

    Posted Jan 09, 2013 04:24 PM

    How is the performance slow? excessive CPU usage? transfer between the 2 servers? (problem I'm experiencing), excessive IO wait time on the disks?