Comment 70 for bug 620074

Just a comment that might have gone unnoticed, but to me appears relevant as this bug again appears to become a collection of multiple issues again as happened with #7372 making that the kernel-devs started to ignore it.

The bisect done by thomas.pi points yields a first bad commit dating from february 2007, while these symptoms first surfaced in 2.6.18, which dates from end 2006.

Bug #7372 basically is from before this first bad commit; the bisect I did in that bug for example pointed towards a problem with NCQ with the CFQ scheduler from November 2006 that clearly was only present for 64bit. See http://bugzilla.kernel.org/show_bug.cgi?id=7372#c112 as a reminder for this proof. I'm not sure that issue got resolved in the end.....no clear pointers on what I could do to help further.

Seeing reports in this bug reporting improvements when switching IO-scheduler and reports on differences between 32/64 bit makes me think those might be more related to that commit. Bottomline is to be sceptical with reports on whether or not a patch helps fully as to me it still appears to be multiple issues that have very similar but difficult to reliably trigger symptoms.

However the test-case of Thomas does bring my system to its knees as well, so definitely a good way to tackle at least part of the problem. But I don't think it is the only problem.