Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752142Ab1DSFGV (ORCPT ); Tue, 19 Apr 2011 01:06:21 -0400 Received: from science.horizon.com ([71.41.210.146]:62553 "HELO science.horizon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751692Ab1DSFGT (ORCPT ); Tue, 19 Apr 2011 01:06:19 -0400 Date: 19 Apr 2011 01:06:18 -0400 Message-ID: <20110419050618.18187.qmail@science.horizon.com> From: "George Spelvin" To: luto@mit.edu Subject: Re: [RFT] Please test rdtsc on various x86-64 hardware (app included) Cc: linux@horizon.com, linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2645 Lines: 74 I'm not doing so well: $ ./evil-clock-test CPU vendor : AuthenticAMD CPU model : AMD Phenom(tm) 9850 Quad-Core Processor CPU stepping : 3 TSC flags : tsc rdtscp constant_tsc nonstop_tsc Using mfence_rdtsc because you don't have an Intel CPU Will test the "mfence;rdtsc" clock. Now test passed : margin 168 with 15744696 samples Load3 test got no data Load test got no data Store test failed: worst error 10 with 617583 samples $ ./evil-clock-test CPU vendor : AuthenticAMD CPU model : AMD Phenom(tm) 9850 Quad-Core Processor CPU stepping : 3 TSC flags : tsc rdtscp constant_tsc nonstop_tsc Using mfence_rdtsc because you don't have an Intel CPU Will test the "mfence;rdtsc" clock. Now test passed : margin 168 with 15666016 samples Load3 test got no data Load test got no data Store test got no data $ ./evil-clock-test CPU vendor : AuthenticAMD CPU model : AMD Phenom(tm) 9850 Quad-Core Processor CPU stepping : 3 TSC flags : tsc rdtscp constant_tsc nonstop_tsc Using mfence_rdtsc because you don't have an Intel CPU Will test the "mfence;rdtsc" clock. Now test passed : margin 168 with 15981720 samples Load3 test got no data Load test got no data Store test got no data Compiled from git revision 8f7d7a62, "Add script to test all pairs." Running as root makes no difference. Other programs: $ ./now_test_all_pairs.sh 0,1: Now test passed : margin 168 with 15007304 samples 0,2: Now test passed : margin 168 with 15288360 samples 0,3: Now test passed : margin 168 with 15539776 samples 1,0: Now test passed : margin 168 with 14890744 samples 1,2: Now test passed : margin 168 with 15266128 samples 1,3: Now test passed : margin 168 with 15322480 samples 2,0: Now test passed : margin 168 with 14978320 samples 2,1: Now test passed : margin 168 with 15109872 samples 2,3: Now test passed : margin 168 with 15207616 samples 3,0: Now test passed : margin 168 with 15043208 samples 3,1: Now test passed : margin 168 with 14686352 samples 3,2: Now test passed : margin 168 with 14945840 samples $ ./timing_test Usage: time [POSIX clock id] Clocks are: 0 (CLOCK_REALTIME) resolution = 0.000000001 1 (CLOCK_MONOTONIC) resolution = 0.000000001 5 (CLOCK_REALTIME_COARSE) resolution = 0.010000000 6 (CLOCK_MONOTONIC_COARSE) resolution = 0.010000000 System is 2.6.38.2 with 8 GB ECC RAM. ATI RD790/SB600 chipset. Hope this helps! -- 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/