From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Stancek Date: Tue, 3 Jan 2017 04:14:48 -0500 (EST) Subject: [LTP] On the performance of lcov... In-Reply-To: <02d71729-2501-cabf-fed0-6f4cc716f565@giref.ulaval.ca> References: <11e74d02-aec3-04c2-a001-39966d8d3430@giref.ulaval.ca> <650748346.6300043.1482001595688.JavaMail.zimbra@redhat.com> <02d71729-2501-cabf-fed0-6f4cc716f565@giref.ulaval.ca> Message-ID: <2053906238.432129.1483434888054.JavaMail.zimbra@redhat.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it ----- Original Message ----- > From: "Eric Chamberland" > To: "Jan Stancek" > Cc: ltp@lists.linux.it > Sent: Monday, 19 December, 2016 8:07:40 PM > Subject: Re: [LTP] On the performance of lcov... > > Hi, > > As suggested, I introduced: > cat ~/.lcovrc > geninfo_gcov_all_blocks=0 > > Now the timings for each steps (see 1st mail) are: > > Now ; Before > ================ > 600s ; 660s > 1269s ; 2113s > 2815s ; 3112s > 2305s ; 2227s > 1401s ; 1391s > ================ > total: > 8390s ; 9503s > > So there is a good gain in the 2nd step, but overall, no big changes... > > I am using > gcov -v > gcov (SUSE Linux) 4.8.1 20130909 [gcc-4_8-branch revision 202388] > > lcov -v > lcov: LCOV version 1.12 > > Are there any other hints or is it "normal" to have these timings? Hi, I'd try to drop lcov_branch_coverage=1 from command line. Or if you need coverage only for part of kernel tree, add also "-k" parameter. I ran following on randomly picked RHEL7.3 x86 host and these are my numbers: Intel(R) Xeon(R) CPU E5-2470 v2 @ 2.40GHz # cat /etc/redhat-release Red Hat Enterprise Linux Server release 7.3 (Maipo) # rpm -qa lcov lcov-1.13-1.noarch # uname -r 3.10.0-512.el7.gcov.x86_64 # rpm -qa gcc gcc-4.8.5-11.el7.x86_64 # grep block /etc/lcovrc # Use gcov's --all-blocks option if non-zero geninfo_gcov_all_blocks = 0 # time lcov -i -c --output-file initial.cov real 4m11.983s user 3m38.892s sys 0m3.400s # time lcov -c --output-file second.cov real 4m14.554s user 3m51.681s sys 0m22.913s # time lcov -a initial.cov -a second.cov -o total.cov Summary coverage rate: lines......: 7.2% (189840 of 2654202 lines) functions..: 9.1% (18434 of 203509 functions) branches...: no data found real 0m25.222s user 0m24.528s sys 0m0.696s # time genhtml -o /var/www/html/test/ total.cov real 7m25.938s user 4m58.467s sys 2m30.020s > Am I posting to the right list to discuss about lcov performance? lcov is maintained separately (mostly by its author) [1], so I'd try to CC ltp-coverage@lists.sourceforge.net and Peter Oberparleiter. [1] http://ltp.sourceforge.net/coverage/lcov.php Regards, Jan