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2 Replies Latest reply: Oct 22, 2012 3:57 AM by Dude! RSS

creating  asm disk on nfs very slow

969742 Newbie
Currently Being Moderated

we are creating asm disk group on nfs, 1 gb it was took almost 3mins,

dd if=/dev/zero of=/oradata/ASM_DATA01 bs=8192 count=13107200

we need 500 gb ? any way we can increase the speed? this is normal or slow ?

DB : 11grr2

OS: sun 11
  • 1. Re: creating  asm disk on nfs very slow
    BillyVerreynne Oracle ACE
    Currently Being Moderated
    NFS uses TCP.

    TCP was never designed to be used as a storage protocol. It is seriously slow. Which is why VoIP for example uses a lighter weight and faster UDP for example.

    However, for a storage protocol state is important. UDP does not provide that. TCP does.

    Another problem is that with NFS you run your storage protocol over a shared medium. There are numerous other network applications and services using that IP network and subnet. A single large scp copying data, or a user watching a HD youtube video, can significantly impact network performance - and drastically decrease the reponse and speed of your storage over TCP.

    IMO, using TCP as a storage protocol (especially for a RDBMS) is silly. The protocol is not suited. The medium is shared. I would expect performance to ALWAYS be an issue in such a case - the rule and not the exception.
  • 2. Re: creating  asm disk on nfs very slow
    Dude! Guru
    Currently Being Moderated
    There are too many unknown factors that could adversely affect your performance. For what it's worth. I can create a 1 GB file in 10 seconds on a 1 Gbit network using a NAS.


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