We upgraded to CiviCRM 5.45.2 on Joomla 3.10.5 and everything was working fine until we attempted to send a mailing to about 1000 recipients. The cron job started failing silently after that, with no notification to us or a visible notification in the dashboard. I contacted our host and they are seeing a 500 error in the Apache access log, but no corresponding entry in the Apache error log, so they said it is coming from either Civi or Joomla.
Example error below:
192.xxx.xxx.xx - - [31/Jan/2022:13:58:35 -0500] "GET /administrator/components/com_civicrm/civicrm/bin/cron.php?name=[redacted]&pass=[redacted] HTTP/1.1" 200 5628 "-" "lwp-request/6.36 libwww-perl/6.36" 0 0 "on:TLSv1.3:TLS_AES_256_GCM_SHA384" 895 3404768 192.252.151.10 www.[redacted].com proxy:unix:/home/[redacted]/.config/php-fpm/.sockets/php-fpm-ZrxRl01wU0Jb5N0KjTcmWLbh8.sock|fcgi://ZrxRl01wU0Jb5N0KjTcmWLbh8 - 192.xxx.xxx.xx
We've never had a similar issue prior to the upgrade, and the only error notices I received were about updating system templates. Has anyone seen a similar issue?