Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 6 Dec 2006 18:05:05 -0500
From:      John Baldwin <jhb@freebsd.org>
To:        freebsd-chat@freebsd.org
Subject:   Re: Venting my frustration with FreeBSD
Message-ID:  <200612061805.05727.jhb@freebsd.org>
In-Reply-To: <20061206134536.0c775367@freen0de>
References:  <200612041443.15154.josh@tcbug.org> <200612061006.56852.jhb@freebsd.org> <20061206134536.0c775367@freen0de>

next in thread | previous in thread | raw e-mail | index | archive | help
On Wednesday 06 December 2006 16:45, soralx@cydem.org wrote:
> 
> > 512-way machine?  Scaling on a 512-way machine is quite a different
> > ball of wax from scaling on 4-way, and scaling up to 32 and 64 is
> > going to be another ball of wax as well.
> 
> can you give a few examples how scaling ability can be a function of
> the number of cores? seems like my curiosity exceeds my imagination
> today -- can't come up with any good reasons why this is true :)

You may make different tradeoffs.  For example, on a 4-cpu system, it may be 
fine to have certain data structures shared across CPUs and protected via a 
lock which avoids the overhead of multiple copies and complexity of updating 
multiple copies of a data structure.  However, with a 512-way system you may 
have to resort to using duplicated per-cpu (or maybe per-cpu group) copies of 
a structure because the tradeoffs are different.

-- 
John Baldwin



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200612061805.05727.jhb>