kern/60526: Post-PAE stable SMP machine freezes

Doug White dwhite at gumbysoft.com
Thu Mar 18 10:30:14 PST 2004


The following reply was made to PR kern/60526; it has been noted by GNATS.

From: Doug White <dwhite at gumbysoft.com>
To: Eugene Grosbein <eugen at kuzbass.ru>
Cc: bug-followup at freebsd.org, stable at freebsd.org, sos at freebsd.org
Subject: Re: kern/60526: Post-PAE stable SMP machine freezes
Date: Thu, 18 Mar 2004 10:23:43 -0800 (PST)

 On Thu, 18 Mar 2004, Eugene Grosbein wrote:
 
 > According to
 > http://freebsd.rambler.ru/bsdmail/freebsd-hackers_2003/msg03936.html
 > the problem may be related to the <ServerWorks ROSB4 ATA33 controller>
 > and ATA write cache (hw.ata.wc=1).
 
 The problem is with DMA mode on these controllers, not write caching.
 Write caching may help to get the data rate up fast enough to trigger the
 bug, and turning it off slows things down.
 
 I HIGHLY recommend using a DIFFERENT controller for disks. The ROSB4 is OK
 for CDROMs and the like, but use a different controller for the system
 drive.  Promise controllers work great. :)
 
 ATA tagging is known to work with only a few disk models.  You should
 enable ATA tags ONLY if you KNOW your drive supports it, and test
 extensively to ensure stability.
 
 -- 
 Doug White                    |  FreeBSD: The Power to Serve
 dwhite at gumbysoft.com          |  www.FreeBSD.org


More information about the freebsd-bugs mailing list