SBP 1394 hard drives hang with Windows XP (rare)

[Mike Berhan]

* From the T10 Reflector (t10 at t10.org), posted by:
* "Mike Berhan" <mikeb at bidali.com>
*
I am looking for some assistance from 1394 bridge chip vendors who may have
knowledge about this problem (or anyone who can point me to a WEB site with
specifics).

I have experienced bus/device hangs on Windows XP with several 1394 hard
drives from different vendors (you get that ugly "delayed write failure"
error).  The hang occurs infrequently but I have narrowed it down to
occurring during very large writes.  In one example, Windows was writing out
3FFh sectors in a single I/O (~512K of data).  This is a valid request,
though rare because you don't often see a request larger than 64K at a time
in Windows.

This could very well be a software issue, but I've experienced other
problems with at least one 1394 bridge chip (in that case, it was problems
dealing with odd aligned buffers).  My theory is that this is a bridge chip
problem though I cannot say that definitively at this time.  I should note
that I did install the "filter" driver that comes with the drive that is
supposed to fix some sort of problem (what, I don't know, they don't
specify).  However, that filter driver didn't fix anything for me.

I have written my own filter driver that limits the I/O size and the problem
is resolved.  However, before I make this filter driver available to others,
I want to know exactly what this problem is.  Is it an I/O larger than 64K
that has an issue?  128K?  256K?  Some scatter/gather limitation?  I thank
you in advance for any information you can provide.  I also have this
information passed into Microsoft as well.

Thank you.

Mike Berhan
busTRACE Technologies


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