Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753198Ab0KDU6z (ORCPT ); Thu, 4 Nov 2010 16:58:55 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:43371 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753188Ab0KDU6u (ORCPT ); Thu, 4 Nov 2010 16:58:50 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version:content-type; b=brt5fKu/Hv2hmyhCPOJwF5ljo9hpitXAU7qxjudV+u8aKVaxm3xW+ZOzdcl9keWnJU PLIAMWqdpek1D1bnP5fkGOMA/cHOqTFW40hq4f6GeXy7pDwaygntcHApxZN38Viy0cm3 PK/4Mmvlhd34aVM93UFvItTzhfq80P+mt6/kQ= From: Francis Moreau To: Reid Kleckner Cc: Frederic Weisbecker , linux-kernel@vger.kernel.org, Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Stephane Eranian , linux-perf-users@vger.kernel.org Subject: Re: perf tools miscellaneous questions References: Date: Thu, 04 Nov 2010 21:58:32 +0100 In-Reply-To: (Francis Moreau's message of "Thu, 04 Nov 2010 08:46:09 UTC") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1962 Lines: 79 Francis Moreau writes: > Francis Moreau writes: > [...] >> >> How could I know the number of cache level on my cpu ? >> >> I tried: >> >> $ perf stat -e cache-misses:u,l1d-loads-misses:u true >> >> Performance counter stats for 'true': >> >> 802 cache-misses >> 937 L1-dcache-load-misses >> >> 0.000996578 seconds time elapsed >> >> $ perf stat -e cache-misses:u,L2-loads-misses:u true >> >> Performance counter stats for 'true': >> >> 788 cache-misses >> 95 LLC-load-misses >> >> 0.001025423 seconds time elapsed >> >> So it looks like you're right: in my case I have this cache >> configuration: >> > > oops sorry, I replied too early... > > so my cache configuration is: > > L1 -> L2 -> LLC > > where L2 misses is given by: 'cache-misses' - 'LLC-load-misses' > > Is that correct ? > > If so, I found 'cache-misses' term very not intuitive IMHO, probably > because I'm not an expert in cpu caches... Well thinking more about it, the above is wrong and I'm lost. If 'cache-misses' is the last level cache misses then how to interpret these results ? $ perf stat -e llc-load-misses:u,llc-store-misses:u true Performance counter stats for 'true': 94 LLC-load-misses 0 LLC-store-misses 0.000981840 seconds time elapsed $ perf stat -e cache-misses:u true Performance counter stats for 'true': 796 cache-misses 0.001345136 seconds time elapsed Here 'cache-misses' value is much more than llc misses one... -- Francis -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/