Description:
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Hi

i start with the most likely solution: http://www.unixguide.net/network/socketfaq/4.5.shtml

yesterday i implemented read/write split into our CMS which works basically but due a benchmark pretty fast such errors starting to flood the log after around 50000-100000 requests with http keep alive (ab -c 250 -n 500000 -k http://application/) which sounds like the machine is running out of ports

[21-Jul-2017 19:11:38 Europe/Vienna] DATABASE-ERROR: corecms/show_content.php - /thelounge.net/corecms/config.inc.php line 659 (parent call: /thelounge.net/corecms/show_content.php on line 17): connection to '*****:3307:corecms' for user 'corecms' failed with 2002: Cannot assign requested address after 26 retries

the only workaround is persistent connections but besides https://bugs.php.net/bug.php?id=74967 is breaking the application sooner or later that don't scale when you have hunredts of workers shared between different users because ou end in number-of-user*worker-count connections