fileserver questions

Wojciech Puchar wojtek at
Fri Aug 29 01:02:06 UTC 2008

> I personally would consider zfs on freeBSD as unstable/experimental on
> everything apart from AMD64's with loads of RAM to spare.  I have tried tuning

for large files UFS offers near-raw performance.
it can't be much better.

it can be less efficient on concurrent operations because MAXBSIZE is 
128KB on FreeBSD.

i don't know why it's still that small!

i changed

#define MAXPHYS         (128 * 1024)   /* max raw I/O transfer size */


#define MAXPHYS         (1024 * 1024)   /* max raw I/O transfer size */

on EVERY machine i own (except those having <128MB RAM) and it works fine, 
while there are huge difference.

you WILL saturade gigabit ethernet port with just 2 gstriped drives 
and many concurrent users fetching files.

make sure gstripe use huge stripes not small (like 256MB), to speed up 
multiple concurrent access instead of single linear read speed.

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