Parallel File System (pfs)

The PFS SAT pfstest tests file I/O on a UFS and a PFS file system, measuring
the performance of writes and reads on each.  Single node write and read
performance is measured for the UFS, single and multiple node write and read
performance is measured for the PFS.

The PFS SAT should be run on no more than 32 nodes for every unique I/O node
making up the PFS stripe directories.

Pass/Fail criteria:
-------------------
Write files with no errors.
Read correct data with no errors.
Performance within expected bounds (if restrictions below met).

pfstest will use performance criteria to determine pass/fail status ONLY
UNDER THE FOLLOWING CONDITIONS:

1) Each stripe directory must be on a unique scsi device, not on the bootnode
   (/dev/io0).  The possible permutations are too great to calculate and test
   if stripes go across devices multiple times.

2) Sufficient free space (<filesize>) must exist to create test files.

3) <blocksize> must be a multiple of stripeunit.

4) <blocksize> * <numnodes> must be greater than or equal to
   <stripeunit> * <number of stripedirs>.

5) <filesize> must be large enough to provide meaningful results (32M). 

6) The -x flag is specified.

The pfstest program will verify these restrictions are met, and print a 
message if they are not.  Performance will still be reported, but will not
be used as a criteria for SAT pass/fail. 
