Block Sizes

[Serguei Patchkovskii]

> 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).