Bug #62658 [Com]: When enable –with-curlwrappers option, stream_get_contents() may cpu 100%

Edit report at https://bugs.php.net/bug.php?id=62658&edit=1 ID: 62658 Comment by: kaiwang dot chen at gmail dot com Reported by: sopl dot wang at gmail dot com Summary: When enable –with-curlwrappers option, stream_get_contents() may cpu 100% Status: No Feedback Type: Bug Package: cURL related Operating System: ALL PHP Version: master-Git-2012-07-25 (Git) Assigned To: pierrick Block user comment: N Private report: N New Comment: I just experienced exactly same problem, which should have been fixed as of 5.3.18/5.4.8/5.5.0 with this patch https://github.com/php/php-src/commit/936553d666405bc783511979b17d78d51905b9cd sopl's analysis is correct, and he was affected because his version is 5.4.7 To reproduce the problem, one need an old php version and a slow connection which could be simulated with: 1) on host A providing http service, enforce traffic control with tc qdisc add dev em1 root handle 1:0 netem delay 500msec 2) on host B runs strace -ttt ./sapi/cli/php <<< '<?php file_get_contents("http://hostA");' 3) on host A, drop the traffic control rule tc qdisc del dev em1 root Then search the strace output for "recvfrom\|select.*= 2\|poll.*= 1" in your vim editor, you will find between matched lines thousands of "select ... = 1" and "poll ... = 0" wasting cpu cycles. PS: curlwrappers has been totally removed from php as voted https://wiki.php.net/rfc/curl-wrappers-removal-rfc Previous Comments: ------------------------------------------------------------------------ [2013-02-18 00:35:56] php-bugs at lists dot php dot net No feedback was provided. The bug is being suspended because we assume that you are no longer experiencing the problem. If this is not the case and you are able to provide the information that was requested earlier, please do so and change the status of the bug back to "Open". Thank you. ------------------------------------------------------------------------ [2012-11-17 00:53:40] pierrick@php.net Here's what I have on my side with today's version of the master branch : select(4, [3], [], [], {15, 0}) = 1 (in [3], left {4, 999876}) poll([{fd=3, events=POLLIN|POLLPRI}], 1, 0) = 1 ([{fd=3, revents=POLLIN}]) recvfrom(3, "1\r\n1\r\n", 16384, 0, NULL, NULL) = 6 select(4, [3], [], [], {15, 0}) = 1 (in [3], left {5, 182}) poll([{fd=3, events=POLLIN|POLLPRI}], 1, 0) = 1 ([{fd=3, revents=POLLIN}]) recvfrom(3, "1\r\n1\r\n", 16384, 0, NULL, NULL) = 6 I compiled it with the same curl version 7.21.6. As you can see I can't reproduce it. My select don't have anything in the Output file descriptor. Can you test if you still have this different output in your strace ? Do you use the exact same script you sent in your previous comment ? ------------------------------------------------------------------------ [2012-10-07 13:59:43] sopl dot wang at gmail dot com You may try use file_get_contents to open a very slow website to help reproduce this problem. When open a very very slow website, this issue will be more evident. ------------------------------------------------------------------------ [2012-10-07 13:49:51] sopl dot wang at gmail dot com Still have issue (a bit different of output, but still cpu 100%) when I build and test on php-5.4.7 GA release. Follow is my build config: ./configure --prefix=/usr/local/webserver/php5.4.7 --with-config-file- path=/usr/local/webserver/php5.4.7/etc --with-mysql=/usr/local/webserver/mysql5 --with-mysqli=/usr/local/webserver/mysql5/bin/mysql_config --with-iconv-dir=/usr --with-freetype-dir --with-jpeg-dir --with-png-dir --with-zlib --with-libxml- dir=/usr --enable-xml --disable-rpath --enable-bcmath --enable-shmop --enable- sysvsem --enable-inline-optimization --with-curl=/usr --with-curlwrappers -- enable-ftp --enable-mbregex --enable-fpm --with-fpm-user=www --with-fpm- group=www --disable-ipv6 --enable-mbstring --with-mcrypt --with-gd=/usr -- enable-gd-native-ttf --with-openssl --with-mhash --enable-pcntl --enable-sockets --enable-gd-jis-conv --disable-debug --enable-sysvshm --enable-soap --with-pdo- mysql=shared,/usr/local/webserver/mysql5 --with-pdo-sqlite=shared --with- sqlite=shared --enable-pdo=shared Test script ----------- ./sapi/cli/php <<<'<?php while(1) file_get_contents("http://www.l4ka.org");' Output ------ poll([{fd=3, events=POLLIN|POLLPRI}], 1, 0) = 0 (Timeout) clock_gettime(CLOCK_MONOTONIC, {26871452, 912511643}) = 0 clock_gettime(CLOCK_MONOTONIC, {26871452, 912536643}) = 0 clock_gettime(CLOCK_MONOTONIC, {26871452, 912553643}) = 0 select(4, [3], [3], [], {15, 0}) = 1 (out [3], left {15, 0}) clock_gettime(CLOCK_MONOTONIC, {26871452, 912606643}) = 0 poll([{fd=3, events=POLLIN|POLLPRI}], 1, 0) = 0 (Timeout) clock_gettime(CLOCK_MONOTONIC, {26871452, 912643643}) = 0 clock_gettime(CLOCK_MONOTONIC, {26871452, 912668643}) = 0 clock_gettime(CLOCK_MONOTONIC, {26871452, 912685643}) = 0 select(4, [3], [3], [], {15, 0}) = 1 (out [3], left {15, 0}) clock_gettime(CLOCK_MONOTONIC, {26871452, 912738643}) = 0 poll([{fd=3, events=POLLIN|POLLPRI}], 1, 0) = 0 (Timeout) clock_gettime(CLOCK_MONOTONIC, {26871452, 912775643}) = 0 clock_gettime(CLOCK_MONOTONIC, {26871452, 912800643}) = 0 clock_gettime(CLOCK_MONOTONIC, {26871452, 912817643}) = 0 select(4, [3], [3], [], {15, 0}) = 1 (out [3], left {15, 0}) System version -------------- LSB Version: :core-4.0-amd64:core-4.0-ia32:core-4.0-noarch:graphics-4.0- amd64:graphics-4.0-ia32:graphics-4.0-noarch:printing-4.0-amd64:printing-4.0- ia32:printing-4.0-noarch Distributor ID: CentOS Description: CentOS release 5.6 (Final) Release: 5.6 Codename: Final Curl version ------------ curl 7.21.6 (x86_64-unknown-linux-gnu) libcurl/7.21.6 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5 Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtsp smtp smtps telnet tftp Features: IDN Largefile NTLM SSL libz ------------------------------------------------------------------------ [2012-09-28 19:44:39] pierrick@php.net Do you still have this issue ? I tried on my local build and everything work as expected. If it doesn't work could you give me more details about your build ? libcurl version ? ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=62658 -- Edit this bug report at https://bugs.php.net/bug.php?id=62658&edit=1