From owner-freebsd-smp Wed Feb 14 19:11:13 2001 Delivered-To: freebsd-smp@freebsd.org Received: from obsecurity.dyndns.org (adsl-63-207-60-67.dsl.lsan03.pacbell.net [63.207.60.67]) by hub.freebsd.org (Postfix) with ESMTP id 80EE837B491 for ; Wed, 14 Feb 2001 19:11:10 -0800 (PST) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 34E4066B26; Wed, 14 Feb 2001 19:11:10 -0800 (PST) Date: Wed, 14 Feb 2001 19:11:10 -0800 From: Kris Kennaway To: Russell Francis Cc: freebsd-smp@FreeBSD.org Subject: Re: possible problem with SMP? Message-ID: <20010214191110.D78224@mollari.cthul.hu> References: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-md5; protocol="application/pgp-signature"; boundary="vni90+aGYgRvsTuO" Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: ; from frussell@p1.cs.ohiou.edu on Wed, Feb 14, 2001 at 02:31:30PM -0500 Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org --vni90+aGYgRvsTuO Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Feb 14, 2001 at 02:31:30PM -0500, Russell Francis wrote: > 50%. I have a threaded application that also runs but no faster that on a > UP kernel. I am just wondering what is going on here any tips on how to > find out would be appreciated thanks. This is actually a FAQ. FreeBSD's userland threads library runs within a single process, so it's not scheduled over multiple CPUs. This is very efficient for UP systems, but not optimal for SMP machines. The LinuxThreads port is an example of rfork()-bases threads (it's a native port of the Linux code) which may be more efficient on SMP for your application. LinuxThreads is also far from optimal - a project is underway to Do Kernel-Supported Threading Right (see the list archives or www.freebsd.org/~jasone/kse) but won't be ready before 6.0-RELEASE, probably. Kris --vni90+aGYgRvsTuO Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (FreeBSD) Comment: For info see http://www.gnupg.org iD8DBQE6i0jNWry0BWjoQKURApqHAJoC6MKM6GF0lWE2zRK9G1QxFbpYOgCgs9N3 ZuIVXGv24LzMuczl/vhH9Oc= =gKlJ -----END PGP SIGNATURE----- --vni90+aGYgRvsTuO-- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message