Message-ID: <508F5D32.3080308@teksavvy.com>
Date: Tue, 30 Oct 2012 00:53:06 -0400
From: Mark Lord <kernel@teksavvy.com>
User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121010 Thunderbird/16.0.1
MIME-Version: 1.0
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Jacob Shin <jacob.shin@amd.com>, Ben Hutchings <ben@decadent.org.uk>,
        Yinghai Lu <yinghai@kernel.org>, Willy Tarreau <w@1wt.eu>,
        stable@vger.kernel.org, Linus Torvalds <torvalds@linux-foundation.org>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        "H. Peter Anvin" <hpa@linux.intel.com>
Subject: Re: Regression from 3.4.9 to 3.4.16 "stable" kernel
References: <508E002B.4090200@teksavvy.com> <20121029064643.GE574@1wt.eu> <508E913D.2080104@teksavvy.com> <1351521658.13356.7.camel@deadeye.wl.decadent.org.uk> <20121029144722.GA23217@jshin-Toonie> <20121029165823.GA6614@kroah.com> <508F0AA6.6010702@teksavvy.com> <20121029230337.GA22444@kroah.com>
In-Reply-To: <20121029230337.GA22444@kroah.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1640
Lines: 37

On 12-10-29 07:03 PM, Greg Kroah-Hartman wrote:
> On Mon, Oct 29, 2012 at 07:00:54PM -0400, Mark Lord wrote:
>> There's something else very wrong when going from 3.4.9 to 3.4.16.
>> I've done it on two machines here, one the AMD-450 server (64-bit),
>> and the other my main notebook (Core2duo 32-bit-PAE).
>>
>> Both systems feel much more sluggish than usual with 3.4.16 running.
>> Reverted them both back to earlier kernels (3.4.9, 3.4.4-PAE),
>> and the usual responsive feel has returned.
>>
>> Vague, I know, but something bad happened in there somewhere.
> 
> That's too vague for me to do anything with, sorry.  Bisection would be
> good if you can figure out how to measure this.

Well, I'd bet Donkeys to Daises that reverting the kernel/sched.c changes
will probably fix the responsiveness, but I haven't done that yet.
I've lost enough time already debugging the other issues.

This is more just an indication that perhaps -stable patches need better review
than they're getting.  Take the setup.c breakage: as soon as I pointed it out,
a few people jumped in with knowledge that it was broken, and that patches
existed to fix it.

That kind of thing should be happening before a -stable release,
though I don't know how you would get the Right People to look
at this stuff then rather than after the fact.  Maybe a topic
for a future kernel summit or something.

Best wishes.
-ml

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/