From owner-freebsd-questions@freebsd.org Fri Apr 2 08:16:12 2021 Return-Path: Delivered-To: freebsd-questions@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 22CF45C7D32 for ; Fri, 2 Apr 2021 08:16:12 +0000 (UTC) (envelope-from ml@netfence.it) Received: from soth.netfence.it (mailserver.netfence.it [78.134.96.152]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "mailserver.netfence.it", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4FBXty6vycz4XQG for ; Fri, 2 Apr 2021 08:16:09 +0000 (UTC) (envelope-from ml@netfence.it) Received: from alamar.ventu (alamar.local.netfence.it [10.1.2.18]) (authenticated bits=0) by soth.netfence.it (8.16.1/8.16.1) with ESMTPSA id 1328G0Pv066515 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Fri, 2 Apr 2021 10:16:01 +0200 (CEST) (envelope-from ml@netfence.it) X-Authentication-Warning: soth.netfence.it: Host alamar.local.netfence.it [10.1.2.18] claimed to be alamar.ventu Subject: Re: Profiling C application To: Scott Bennett , freebsd-questions@freebsd.org References: <202011281922.0ASJMtiH020409@sdf.org> <16423477-7854-20bf-58ff-c174375e37fe@netfence.it> <202011291202.0ATC2rbO024634@sdf.org> From: Andrea Venturoli Message-ID: <1139046c-7f48-dbdb-0790-bb821e9e9001@netfence.it> Date: Fri, 2 Apr 2021 10:16:00 +0200 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:78.0) Gecko/20100101 Thunderbird/78.9.0 MIME-Version: 1.0 In-Reply-To: <202011291202.0ATC2rbO024634@sdf.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4FBXty6vycz4XQG X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=pass (policy=none) header.from=netfence.it; spf=pass (mx1.freebsd.org: domain of ml@netfence.it designates 78.134.96.152 as permitted sender) smtp.mailfrom=ml@netfence.it X-Spamd-Result: default: False [-1.80 / 15.00]; RCVD_TLS_ALL(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:78.134.96.152]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; HAS_XAW(0.00)[]; ARC_NA(0.00)[]; NEURAL_SPAM_SHORT(1.00)[1.000]; SPAMHAUS_ZRD(0.00)[78.134.96.152:from:127.0.2.255]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[78.134.96.152:from]; RCPT_COUNT_TWO(0.00)[2]; DMARC_POLICY_ALLOW(-0.50)[netfence.it,none]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:35612, ipnet:78.134.0.0/17, country:IT]; RCVD_COUNT_TWO(0.00)[2]; MAILMAN_DEST(0.00)[freebsd-questions] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Apr 2021 08:16:12 -0000 On 11/29/20 1:02 PM, Scott Bennett wrote: > Andrea Venturoli wrote: > >> On 11/28/20 8:22 PM, Scott Bennett via freebsd-questions wrote: >> >>> I see you already have one response at least to your question, but >>> perhaps a simpler one is to use a now ancient BSD UNIX tool called gprof(1), >>> along with the compiler option -pg. (See the gprof(1) man page for the >>> details.) Note, too, that you may want to link your program to the profiling >>> versions of system libraries as explained in the man page. >> >> I didn't mention gprof because it stopped working when FreeBSD switched >> from GCC to clang. Or, maybe, it was my fault, not being able to get it >> working again. >> >> That was a long time ago, however; if nowadays it's a viable solution, >> I'm happy to hear this. >> > Bugzilla only turned up one PR that may have a bearing on that. See > PR 198462 from 2017 and 10.1. There's no sign that anyone, other than the poster > of the PR, even looked into it, an unfortunately common situation. > Thank you for pointing out the problem. Do you still have a test case you > could try? Sorry for answering so late... Today I need once again to profile a program and, since valgrind is currently broken :-(, I decided to give gprof another shot (on 12.2/amd64). As per gprof(1), I added "-pg" to compilation and linking phase, i.e. my program compiles with something like: c++ -c -ggdb -O0 -pg ... -o a.o a.cxx c++ -c -ggdb -O0 -pg ... -o b.o b.cxx ... c++ -o a.exe a.o b.o ... -lthr -pg ... When I run it, I get: % ./a.exe ld-elf.so.1: /lib/libc.so.7: Undefined symbol "__progname" gprof(1) states that "The -pg option also links in versions of the library routines that are compiled for profiling". Alas, this does not seem to be the case: ldd a.exe a.exe: libarchive.so.13 => /usr/local/lib/libarchive.so.13 (0x8004a0000) libboost_filesystem.so.1.72.0 => /usr/local/lib/libboost_filesystem.so.1.72.0 (0x800574000) libboost_program_options.so.1.72.0 => /usr/local/lib/libboost_program_options.so.1.72.0 (0x800591000) libboost_system.so.1.72.0 => /usr/local/lib/libboost_system.so.1.72.0 (0x8005f1000) libcrypto.so.111 => /lib/libcrypto.so.111 (0x8005f5000) libexpat.so.1 => /usr/local/lib/libexpat.so.1 (0x8008e7000) liblzo2.so.2 => /usr/local/lib/liblzo2.so.2 (0x800914000) liblzma.so.5 => /usr/lib/liblzma.so.5 (0x800944000) liblz4.so.1 => /usr/local/lib/liblz4.so.1 (0x800970000) libbz2.so.4 => /usr/lib/libbz2.so.4 (0x80099e000) libz.so.6 => /lib/libz.so.6 (0x8009b4000) libc.so.7 => /lib/libc.so.7 (0x8009d0000) libc++.so.1 => /usr/lib/libc++.so.1 (0x800dc6000) libcxxrt.so.1 => /lib/libcxxrt.so.1 (0x800e93000) libm.so.5 => /lib/libm.so.5 (0x800eb5000) libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x800ee7000) libthr.so.3 => /lib/libthr.so.3 (0x800f01000) libmd.so.6 => /lib/libmd.so.6 (0x800f2e000) I think I should change "-lthr" to "-lthr_p", but that does not make any difference. Ditto if I add "-lc_p": apparently these are ignored. What am I doing wrong? BTW, would solving this be enough or would I later hit the fact that I'm using third party libraries (e.g. boost) which are not compiled with "-pg"? bye & Thanks av.