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DPM 2010 & Falconstor RRS feed

  • Question

  • We are currently testing a Falconstor VTL library so we can ascertain benefits. I've noticed quite poor performance and wondered if this was a DMP thing or a Falconstor thing (im asking them too)

     

    Configuration ect is all OK, the problem comes when the tape backup runs. Network communication only goes to about 2.5% over a GB network link and it stays there for about 1-2 minutes and then all network traffic stops, the backup continues to run in the monitoring area but no data is actually being sent. After about 3-4 minutes of network inactivity more data is sent and the cycle continues, the backups to complete but the performance is very slow.

     

    Just wondered if anyone knew where there was anything we can do DPM side to get it to send the data all the time and not stop every couple of minutes.

    • Moved by MarcReynolds Wednesday, November 17, 2010 6:16 PM (From:Data Protection Manager)
    Wednesday, November 17, 2010 5:31 PM

Answers

  • The network is involved because Falconstor is Virtual Tape Library Software, so the traffic is being streamed over the network to the Falconstor device where it's logically put on to tapes, but physically it's going on to a SAN.

     

    We're not talking about a large amount of data only about 200GB in total but we only reach average speeds of 15-20MB/s because of the long wait between transmitions times and the short bursts of data when DPM does finally transmit data.

     

    *RESOLVED*

     

    There was an iSCSI network card driver problem, new driver and problem gone.

    • Marked as answer by PureTech Friday, November 26, 2010 3:27 PM
    Tuesday, November 23, 2010 10:03 AM

All replies

  • Hi Marc,

    why is the network involved --> assuming you are doing "short term to tape" D2T ?

    It seems the agent cannot deliver data quick enough by some local cause.
    One reason can be if you are protecting a volume with great many (million and more) small files.
    On larger data-sets you should be able to reach ~60MB/sec.

    One other thing that acts like vicious circle in terms of 'flow'.
    If data up-bringing is not enough (sustained) for the LTO to stay streaming it starts 'shoe shining' (repositioning) and even if DPM server has received enough data it must wait for that.

     


    \R2 This posting is provided "AS IS" with no warranties, and confers no rights
    Sunday, November 21, 2010 10:40 AM
  • The network is involved because Falconstor is Virtual Tape Library Software, so the traffic is being streamed over the network to the Falconstor device where it's logically put on to tapes, but physically it's going on to a SAN.

     

    We're not talking about a large amount of data only about 200GB in total but we only reach average speeds of 15-20MB/s because of the long wait between transmitions times and the short bursts of data when DPM does finally transmit data.

     

    *RESOLVED*

     

    There was an iSCSI network card driver problem, new driver and problem gone.

    • Marked as answer by PureTech Friday, November 26, 2010 3:27 PM
    Tuesday, November 23, 2010 10:03 AM