Thread

  1. Block Sizes

    Cary B. O'Brien <cobrien@access.digex.net> — 1998-01-06T03:43:19Z

    Oracle has adjustable disk block sizes, tuneable per instance
    (can you change it after install??  can't remember).  In any
    case the default is 2k or 4k, and things almost always go
    faster with larger block sizes.  On one project we needed to
    go fast and had disk space to burn, so we upped it to 16k.
    This was all _without_ using raw devices.
    
    My *gut* feeling is that the underlying block size is a trade-off,
    smaller blocks are better for small transactions, bigger blocks
    are better for bulk load/extract operations, with a penalty for 
    finding a single row.  Optimum depends on the application, but is
    somewhere between 2 and 32 k.
    
    How hard would it be for postgresql to support adjustable block sizes? 
    Just wondering.
    
    -- cary
    cobrien@access.digex.net