fsx is a filesystem exerciser that is used to test both local and network filesystems.

Dave Jones has written a useful history of fsx and gathered a collection of fsx variants. This version of fsx is the original fsx source that was released in 2001 with additional enhancements from various Apple folks.

This release adds the following options:

-d duration
number of hours for the tool to run
tests using an extended attribute rather than a file
-f forkname
test the named fork of fname
-g logpath
path for .fsxlog file
write 0s instead of creating holes (i.e. sparse file)
interactive mode, hit return before performing the current operation
-l logpath
path for XILog file
debug output for all operations
write output in XML (XILOG)
call fsync before closing the file
mix cached and un-cached read/write ops
-G logsize
#entries in oplog (default 1024)
-F flen
the upper bound on file size (default 262144)
start interactive mode since operation opnum
slow motion mode: wait 1 second before each op
mapped read operations DISabled
-T datasize
size of atomic data elements written to file [1,2,4] (default 4)