Last Updated: August 14th, 2004 by Robin Miller

	This is a major release of 'dt', which includes several bug
fixes and new features.

	The following changes were made to 'dt' Version 15.10:

     o	Ported to AIX.
     
     o	Added enable=hazard to support "dt stress" test configuration
	under Hazard test suite.  This option causes errors to be written
	to stdout, instead of stderr, with a special severity prefix.
       
     o	Added enable/disable=fsalign to allow non-block aligned I/O
	for file system testing.  The default is off (disabled), so
	variable lengths via incr=var and non-block random offsets
	are possible.  Use enable=fsalign to enable previous behavior.
       
     o	Fixed random I/O offsets for large capacity disks.  Previously
	when compiled for 32 bits, offsets were truncated to 32 bits.

     o	When position=offset option is used, prevent I/O prior to this
	offset when doing reverse I/O.

     o	For Linux, use IOCTL to obtain sector size & partition capacity.
	Why? The partition capacity may not be the actual disk capacity,
	and allows bypassing 'dt' calculating capacity for random I/O.

     o	For HP-UX, added qdepth=N option to set a new queue depth.  This
	setting is "sticky", meaning the previous setting isn't restored.
	The default queue depth on current HP-UX is 8, but this option
	can be used to generate a higher I/O load when doing async I/O.
       
     o	Added support for trigger=action option, which is invoked when
	errors occur.  When using the "trigger=cmd:string" type, the
	tester can then do special handling of errors, like panic'ing
	the system, doing expanded corruption analysis, etc.

	trigger=type     The trigger to execute during errors.

	Trigger Types:
            br = Execute a bus reset.
            bdr = Execute a bus device reset.
            seek = Issue a seek to the failing lba.
            cmd:string = Execute command with these args:
              string dname op dsize offset position lba errno
	      where:
	        dname = The device/file name.
	        op = open/close/read/write/miscompare
	        dsize = The device block size.
	        offset = The current file offset.
	        position = The failing offset within block.
	        lba = The logical block address (relative for FS).
	        errno = The error number on syscall errors.

            The first three options require Scu in your PATH, since
	Scu is used to execute these operations.


	Within HP, the updated 'dt' kits are located @ URL:

		http://www.zk3.dec.com/~rmiller/dt.html

	External to HP, you can obtain 'dt' kits from URL:

		http://www.bit-net.com/~rmiller/dt.html

Cheers,
Robin
