On 03/25/2012 01:39 PM, Hugh Dickins wrote:
> On Fri, 23 Mar 2012, Jason Mattax wrote:
>> On 03/23/2012 06:05 AM, Hugh Dickins wrote:
>>> I'm not surprised that you saw no problem on 2.6.32.27, but I am
>>> very surprised that you see the problem on 2.6.33.1 - I'm wondering
>>> if that's a typo for something else, or a distro kernel which actually
>>> contains changes from later releases?
>> I can't say why I saw it then, but I got the 2.6.33.1 kernel off of
>> http://www.kernel.org/pub/linux/kernel/v2.6/ so that I wouldn't have to worry
>> about distribution changes when reporting the bug here. I just recompiled the
>> source and verified that it is still affected even with the newest firmware.
> Thank you for going to that trouble to narrow it down, thank you for
> confirming, and I apologize for shedding doubt on your finding.
>
> It appears that there's something else involved here, which I know nothing
> about as yet; perhaps an earlier change in block layer handling of discard.
>
> Although it's just history now, I ought to investigate once my Vertex2
> arrives - well, several weeks later, I won't have time immediately.
>
> Please would you clarify one thing.  2.6.33.1 was the earliest kernel
> you saw the slowdown on.  I assume from that that you tried 2.6.33 itself,
> and it did not show the slowdown.  Or were you testing releases in some
> other order? if so please let me know the latest without the slowdown.
>
> Thanks,
> Hugh
>
I attempted to test on 2.6.33, but I was unable to get it to boot with 
the exact same .config file as the one I used for 2.6.33.1, based on the 
bit of the stack trace I could see it looked like something was killing 
init. Everything else was the same between booting those kernels and 
2.6.32.27 booted just fine as did all the kernels I tested past 
2.6.33.1, since I was focused on finding where the flaw was I figured 
that within 2 revisions was good enough.

in summary
2.6.32.27 - booted and swapon worked fine
2.6.33 - failed to boot
2.6.33.1 - booted and swapon was slow

Looking back at it it appears that you weren't in the list of 
maintainers I got by running the suggested script, I'll attach email, 
and its attachments to this one.
Jason

-- 
Jason Mattax
575-418-1791
jmattax@storytotell.org