Block Sizes

Joe Landman landman at
Thu Oct 31 21:01:27 PST 2002

I wonder if you could use fread/fwrite, some clever malloc'ing of a
large buffer, and some simple API to create something similar under


On Thu, 2002-10-31 at 21:40, Serguei Patchkovskii wrote:
> > The filesystem is already tunned. In the SGI machine, we are trying to
> test
> > block sizes bigger than 4k, like 8k and 16k, and the performance grows a
> little.
> SGI IRIX has some very nice extensions for optimizing large I/O. Look up
> O_DIRECT in the open(2) manual page - with a properly aligned buffer,
> large I/O transfer sizes (a megabyte or so), and some buffer management,
> your transfer rates will approach what the raw hardware is capable of
> providing.
> This can be optimized further, by placing your files on a real-time section
> of an
> xfs file system (see xfs(4) manual page).
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Joseph Landman, Ph.D
Scalable Informatics LLC,
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