linux-kernel - perf, H/W counters

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 27 May 2011 13:33:54 -0600
From:	David Ahern <dsahern@...il.com>
To:	"linux-perf-users@...r.kernel.org" <linux-perf-users@...r.kernel.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: perf, H/W counters - ESX hosted VM


Has anyone successfully used perf within an ESX VM? dmesg shows a PMU is
discovered:

dmesg | grep -i performance
Performance Events: Nehalem/Corei7 events, Intel PMU driver.

yet data from it is nonsensical:

perf stat -v -- /tmp/a

task-clock-msecs: 20593318 20593318 20593318
context-switches: 2 20593318 20593318
CPU-migrations: 0 20593318 20593318
page-faults: 387 20593318 20593318
cycles: 10737418235 20593318 20593318
instructions: 10737418235 20593318 20593318
cache-references: 10737418235 20593318 20593318
cache-misses: 10737418235 20593318 20593318

 Performance counter stats for '/tmp/a':

      20.593318  task-clock-msecs         #      0.988 CPUs
              2  context-switches         #      0.000 M/sec
              0  CPU-migrations           #      0.000 M/sec
            387  page-faults              #      0.019 M/sec
    10737418235  cycles                   # 521403.022 M/sec
    10737418235  instructions             #      1.000 IPC
    10737418235  cache-references         # 521403.022 M/sec
    10737418235  cache-misses             # 521403.022 M/sec

    0.020837863  seconds time elapsed

David

/tmp/a  -- a step above 'sleep 1'

#!/bin/sh

declare -i i=0;
declare -i sum=0;
while [ $i -lt 1000 ]
do
	sum=$((sum + i))
    i=$((i+1))
done
echo "sum $sum"
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/