I believe that I have brought this up previously, but I am now hitting this on our install. I have a large "umbrella" task that I am using to track the progress of an ongoing project. As a result, this task has a lot of blocking tasks and has a large number of associated transactions.
It has now created the stage that I am unable to view the task, and instead I get a 502 error.
>>> UNRECOVERABLE FATAL ERROR <<< Maximum execution time of 30 seconds exceeded /usr/src/phabricator/src/applications/maniphest/storage/ManiphestTransaction.php:311 ┻━┻ ︵ ¯\_(ツ)_/¯ ︵ ┻━┻