[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <Pine.LNX.4.61.0610310857280.23540@yvahk01.tjqt.qr>
Date: Tue, 31 Oct 2006 08:59:22 +0100 (MET)
From: Jan Engelhardt <jengelh@...ux01.gwdg.de>
To: Zachary Amsden <zach@...are.com>
cc: Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: 2.6.18 is problematic in VMware
>> I have observed a strange slowdown with the 2.6.18 kernel in VMware. This
>> happened both with the SUSE flavor and with the FC6 installer CD (which I
>> am trying right now). In both cases, the kernel "takes its time" after the
>> following text strings:
>>
>> * Checking if this processor honours the WP bit even in supervisor mode...
>> Ok.
>> * Checking 'hlt' instruction... OK.
>>
>> What's with that?
>
> Thanks. It is perhaps the jiffies calibration taking a while because of the
> precise timing loop. Are you reasonably confident that it is a regression in
> performance over 2.6.17?
Yes. I am not exactly sure if it's something in jiffies calibration
(because of the 'WP bit/supervisor' thing too), so maybe I thought it
was the newly-introduced SMP alternatives. I gotta check that.
> The boot sequence is pretty complicated, and a lot of
> it is difficult / slow to virtualize, so it could just be alternate timing
> makes the boot output appear to stall, when in fact the raw time is still about
> the same. I will run some experiments.
Booting with 'time' shows that the virtual time increases as usual, i.e.
[ 9.00] checking if wp bit...
[15.00] next message here
-`J'
--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists