#30852 [Fbk->Csd]: socket_select() fails when managing large numbers of sockets

ID: 30852 User updated by: jed at jed dot bz Reported By: jed at jed dot bz -Status: Feedback +Status: Closed Bug Type: Sockets related Operating System: Windows XP SP2 PHP Version: 5.0.2 New Comment: Thumbs up, Wez. -#include <winsock2.h> +#define FD_SETSIZE 512 +#include <winsock2.h> Too bad that can't be turned into a php.ini option for the Sockets extension... Previous Comments: ------------------------------------------------------------------------ [2004-11-21 14:52:42] wez@php.net Please try using this CVS snapshot: http://snaps.php.net/php5-STABLE-latest.tar.gz For Windows: http://snaps.php.net/win32/php5.0-win32-latest.zip Windows can only select(), by default, a maximum of 64 handles at one time. 5.0.3 changes this limit to 256 in the Streams subsystem; you can try this yourself with a stable snapshot and using the native functions stream_socket_client(), stream_socket_server() and stream_select(). I would expect this change to also work with the sockets extension. It builds ok here with 5.0.3, so it sounds like you do indeed have a configuration issue. Short version: try a 5.0.3 snapshot, it should behave better . ------------------------------------------------------------------------ [2004-11-21 00:44:26] jed at jed dot bz Description: ------------ Posted to php.general. Posted here on behalf of original bug discoverer, as I wrote a large test case for it. PHP 5.0.2 CLI Windows XP SP 2 with DEP excepted for PHP-CLI (DEP *was* a problem early, but I excepted it for php.exe) socket_select() will fail when managing a large number of sockets. The sockets extension itself can manage a bunch, but when socket_select() is attempted with a 'read' array larger than exactly 64 sockets, it prints out the following message and dies: Warning: socket_select(): unable to select [0]: An operation was attempted on something that is not a socket. PHP's problem? My problem? A print_r of the array before feeding it to socket_select shows this: Array ( [1] => Resource id #4 [2] => Resource id #5 [3] => Resource id #6 (...) [64] => Resource id #67 [65] => Resource id #68 ) Valid resources, I'd assume. Zero-basing the array causes the same problem. If there are more than exactly 64 sockets in the array fed to socket_select for the read parameter socket_select() will fail. Due to lack of time I'll only submit the test case for read, but write and except might be prone to the same problem. Let's tackle one at a time. Latest CVS was unusable as the sockets extension currently doesn't link correctly (numerous PHP startup warnings were encountered when starting php just for php -v)... The snaps I used to obtain this result were 5.0.x-dev 200411201730 ("5.0.3-dev") 5.1.x-dev 200411201930 Might have been misconfiguration on my end, because 5.0.x popped up a box reporting a mismatch between extensions even after I changed extension_dir to the snapshot package's extensions. Reproduce code: --------------- The Server http://labs.jed.bz/HCJ/server.php.txt The Load Client http://labs.jed.bz/HCJ/load.php.txt When executing, make sure $max_connections in the server is exactly equal to $connections in the load tester (or, if you prefer, make it one under, and telnet in to the server to make the last one). Expected result: ---------------- ... connecting #65 of 65 ... ok waiting for spew Array ( ... ) spew! done! Actual result: -------------- [63] => Resource id #67 [64] => Resource id #68 ) Warning: socket_select(): unable to select [0]: An operation was attempted on something that is not a socket. in F:\Projects\HCJ\load.php on line 39 spew! done! ---------------- This appeared in my debugger output while I was messing with getting a backtrace (possible in VS?). Interest you? First-chance exception at 0x7c81eb33 in php.exe: 0x000006A6: The binding handle is invalid. ---------------- I can't recompile with debug symbols at this point, I'm unfortunately pressed for time. Perhaps someone can run it through VS and see what comes up. ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=30852&edit=1