improving concurrency/performance

From: John Madden (no email)
Date: Fri Nov 04 2005 - 14:01:00 EST

  • Next message: Huaqing Zheng: "Re: improving concurrency/performance"

    I've had great experience with the performance of Cyrus thus far, but I'm testing
    a migration at the moment (via imapcopy) and I'm having some pretty stinky
    results. There's no iowait (4 stripes on a 2Gbps SAN), no cpu usage, nothing
    waiting on the network, and still I'm seeing terrible performance. I assume this
    points to something internal, such as concurrency on the db files.

    I've converted everything to skiplist already, I've tweaked reiserfs's mount
    options, what little Berkeley still used appears to be ok (no waiting on locks and
    such), so I'm at a loss. Is there a general checklist of things to have a look
    at? Are their tools to look at the metrics of the skiplist db's (such as
    Berkeley's db_stat)? Am I doomed to suffer sub-par performance as long as IMAP
    writes are happening?

    Migration's coming on the 24th. I'm now officially sweating. :)

    Thanks,
      John

    -- 
    John Madden
    UNIX Systems Engineer
    Ivy Tech Community College of Indiana
    ----
    Cyrus Home Page: http://asg.web.cmu.edu/cyrus
    Cyrus Wiki/FAQ: http://cyruswiki.andrew.cmu.edu
    List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
    

  • Next message: Huaqing Zheng: "Re: improving concurrency/performance"





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