Topic
4 replies Latest Post - ‏2013-10-21T19:19:27Z by ord_mike
ord_mike
ord_mike
14 Posts
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Pinned topic Poor MPIO speed on DS3300 with Windows Server 2012

‏2013-09-16T21:51:29Z |

I'm having trouble with MPIO on a new server I set up recently. It's an x3550M4 with Intel NICs. 4 are the builtin Intel I350's. And I have a dual port PCI Intel I340-T2. Windows Server 2012. I have this server connected to 2 different SANs, one is a Cisco NSS326, and the other is an IBM DS3300. The NSS326 has 2 NICs and works great, using round robin. Disk IO is good, and iSCSI saturates both NICs when I copy data to/from it. I'm having trouble with disk IO speed on the DS3300. If I set it to round robin with subset, and it only uses one NIC, speeds are pretty good (with crystal disk):

Sequential Read :   103.471 MB/s
Sequential Write :    69.447 MB/s
Random Read 512KB :    36.963 MB/s
Random Write 512KB :    44.258 MB/s


If I enable round robin so it uses 2, 3 or 4 NICs, speeds drop to abysmal levels, like 1/10th of the rr-subset speed. I started the disk test 30 minutes ago, it still hasn't finished.
My network gear is pretty good- I have 2 Cisco 3560G switches. They are connected to our core 3750 switch, but I don't think any traffic passes that way since the server NICs & SANs are on either one of 2 subnets, so iSCSI traffic stays within the switch. One other thing that may or may not be relevant- my NICs are using the builtin Microsoft drivers b/c I can't seem to find any Intel drivers for them on the IBM site as yet.

I'm at a loss as to what is the problem here. I've torn down and rebuilt my MPIO/iSCSI settings multiple times. I triple checked everything I can think of. Any advice greatly appreciated.

  • AndersLorensen
    AndersLorensen
    156 Posts
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    Re: Poor MPIO speed on DS3300 with Windows Server 2012

    ‏2013-09-17T07:24:51Z  in response to ord_mike

    The DS3300 does not support ALUA. So you have 1 active controller you can use, and one passive controller, that you cannot use. If you use the passive controller, the SAN fails over the LUN to the passive controller. This takes a bit of time that eats huge chunks of performance.

     

    When you set Round Robin the SAN fails over the LUN between the controllers constantly, and as a result you get VERY poorr performance.

     

    --

    Anders

    • ord_mike
      ord_mike
      14 Posts
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      Re: Poor MPIO speed on DS3300 with Windows Server 2012

      ‏2013-09-17T14:57:30Z  in response to AndersLorensen

      OK so if I set my MPIO to RR-subset and only controller A NICs active, I have my best speed tests so far.

      Sequential Read :              132.782 MB/s
      Sequential Write :                 81.601 MB/s
      Random Read 512KB :       63.436 MB/s
      Random Write 512KB :        46.789 MB/s
       

      Thanks a million Anders.

      Updated on 2013-09-17T14:57:53Z at 2013-09-17T14:57:53Z by ord_mike
      • Archtoronto
        Archtoronto
        1 Post
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        Re: Poor MPIO speed on DS3300 with Windows Server 2012

        ‏2013-10-21T18:13:38Z  in response to ord_mike

        We were told by IBM that the DS3300 did not support the Windows 2012 iSCSI initiator.   Did you have to configure it in a different way to Windows 2008R2 to get it working?  So far we have not been successful

        • ord_mike
          ord_mike
          14 Posts
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          Re: Poor MPIO speed on DS3300 with Windows Server 2012

          ‏2013-10-21T19:19:27Z  in response to Archtoronto

          The iSCSI initiator is very similar in 2008 and 2012 Server. I set it up the same in both.

          Did you allow the host to access the lun in Storage Manager?

          Are you using chap with iscsi, and if so make sure you enter the password in your initiator.

          As long as these things are configured you should have no issue.