Bug #80412 [Com]: PHP-FPM : PDO / Broken Pipe when DBMS ends the connection

Edit report at https://bugs.php.net/bug.php?id=80412&edit=1 ID: 80412 Comment by: heavy-traffic-website at yopmail dot com Reported by: heavy-traffic-website at yopmail dot com Summary: PHP-FPM : PDO / Broken Pipe when DBMS ends the connection Status: Open Type: Bug Package: PDO Core Operating System: Debian 11 PHP Version: 7.4.12 Block user comment: N Private report: N New Comment: It doesn't need any strategy or interval or whatever. Just to connect like the first persistent connexion when the pipe is broken. That's all. Independantly what is the DBMS used, even if Haproxy break the pipe. Previous Comments: ------------------------------------------------------------------------ [2020-11-24 23:23:09] heavy-traffic-website at yopmail dot com Thank you for your review. The code PDO::__contruct() is very explicit : I want a persistent connection. And this line works until the pipe exists. Maybe not everybody use HAproxy between Galera Cluster and PHP-FPM but, the code to keep it working without error is really poor : try{ new PDO() }catch(){ new PDO() } Please don't justify this is normal, when the pipe broke whatever the reason is : PHP/PDO should DETECT the broken PIPE and treat the __construct like no one persistent connection exists yet inside each thead. We are on the ends of 2020, it has to think logic and serve the langage, not saying like 10 year ago : it is still a feature. ------------------------------------------------------------------------ [2020-11-24 23:06:36] daverandom@php.net Note also that there is no implied re-connect on remote connection drop in any PHP-RDBMS drivers (afaik). It is generally assumed that reconnection would be a thing that should be dealt with in userland, as there is no universal strategy for interval, back-off or max retry count. ------------------------------------------------------------------------ [2020-11-24 23:03:25] daverandom@php.net Note that this would be per-driver behaviour, specific to the RDBMS being used rather than a generic PDO problem. Any further information on the RDBMS system/version affected would be useful - obviously the DSN used with PDO indicates that MySQL is affected by this. ------------------------------------------------------------------------ [2020-11-24 23:00:16] heavy-traffic-website at yopmail dot com Description: ------------ Related to this very old bug reported 10 years ago => https://bugs.php.net/bug.php?id=53287 (johannes@php.net) was wrong - the bug still exists and no one fixed it. --> Please consider the bug onto the PHP side, not the DBMS side. ------------------------ new PDO("mysql:host=127.0.0.1;dbname=XXX", "XXX", "XXX", [ PDO::ATTR_PERSISTENT => true ]); PHP-FPM have threads with broken persistent connections and SHOULD try to reconnect a new one connection rather than CRASHING an exception in the case where send of 5 bytes failed with errno=32 Broken pipe appens in __construct. Test script: --------------- With php7.4-fpm, i have some threads and when i have a wide blank time between DBMS and PHP, probably the timeout of the DBMS break the pipe (default: 8h), however PHP/PDO don't care and throw an exception instead of making a new one connection, inside each thread alive. Currently, I have to try{ new PDO() }catch(){ new PDO() } to be working without error, it sucks ! Expected result: ---------------- The PDO side CAN be patched, so this is a bug. It is expected that PDO will try to reconnect silently if the case described appears, before lauching any exception. And if any exception has to be launched, it will certainly will not be these one but the new connection exception. Actual result: -------------- Catched Exception : PDO::__construct(): send of 5 bytes failed with errno=32 Broken pipe ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=80412&edit=1