Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 27 Dec 2004 14:52:40 -0500
From:      John Baldwin <jhb@FreeBSD.org>
To:        freebsd-hackers@FreeBSD.org
Cc:        Kris Kennaway <kris@obsecurity.org>
Subject:   Re: HTT/SMP servers instability on 5.3-STABLE
Message-ID:  <200412271452.40348.jhb@FreeBSD.org>
In-Reply-To: <20041210204824.GA53907@xor.obsecurity.org>
References:  <36627.194.210.13.66.1102679886.squirrel@194.210.13.66> <20041210204824.GA53907@xor.obsecurity.org>

next in thread | previous in thread | raw e-mail | index | archive | help
On Friday 10 December 2004 03:48 pm, Kris Kennaway wrote:
> On Fri, Dec 10, 2004 at 05:58:06AM -0600, klr@6s-gaming.com wrote:
> > I've heard it can penalize performance because the scheduler isn't
> > optimized for logical CPUs.  Does having HTT enabled impacts the
> > stability of the system?
>
> No.

Actually, for 5.3 it does.  HEAD has the problem fixed, not sure about 
RELENG_5 yet, but due to the way IPIs are done in 5.3, having more than 2 
CPUs can be very destabilizing, so disabling HTT on a 2-way system so that it 
goes from 4 CPUs to 2 CPUs can help stability very much.

-- 
John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200412271452.40348.jhb>