From owner-freebsd-current Sat Jan 8 10:38:32 2000 Delivered-To: freebsd-current@freebsd.org Received: from khavrinen.lcs.mit.edu (khavrinen.lcs.mit.edu [18.24.4.193]) by hub.freebsd.org (Postfix) with ESMTP id CCE331569D for ; Sat, 8 Jan 2000 10:38:29 -0800 (PST) (envelope-from wollman@khavrinen.lcs.mit.edu) Received: (from wollman@localhost) by khavrinen.lcs.mit.edu (8.9.3/8.9.3) id NAA51522; Sat, 8 Jan 2000 13:38:28 -0500 (EST) (envelope-from wollman) Date: Sat, 8 Jan 2000 13:38:28 -0500 (EST) From: Garrett Wollman Message-Id: <200001081838.NAA51522@khavrinen.lcs.mit.edu> To: Mohit Aron Cc: wollman@khavrinen.lcs.mit.edu (Garrett Wollman), freebsd-current@freebsd.org Subject: Re: performance of FreeBSD-current as SMP In-Reply-To: <200001081834.MAA14332@cs.rice.edu> References: <200001081832.NAA51499@khavrinen.lcs.mit.edu> <200001081834.MAA14332@cs.rice.edu> Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG < said: > Well, some difference is to be expected. But 22% ???? Flaws in the Intel SMP design make it more expensive than it ought to be. Things like atomic RMW cycles are very, very expensive. (We had a discussion about six months ago about how expensive something like a locked xchg instruction actually is.) -GAWollman -- Garrett A. Wollman | O Siem / We are all family / O Siem / We're all the same wollman@lcs.mit.edu | O Siem / The fires of freedom Opinions not those of| Dance in the burning flame MIT, LCS, CRS, or NSA| - Susan Aglukark and Chad Irschick To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message