If a backend crashes/killed due to OOM, then the FDs opened in the postmaster aren't closed, so after a few crashes you can end up with a multiple as many FDs opened. Which can then lead to queries failing with "too many opened files".
$ postgres -c io_method=io_uring & $ lsof -p 3732231 2>/dev/null |grep -c io_uring 284 $ kill -9 3732232 $ lsof -p 3732231 2>/dev/null |grep -c io_uring 568 I'm not sure, but that might be related to these other errors. error_severity | ERROR sql_state_code | XX000 message | could not read blocks 122..126 in file "base/246942/132857974": Operation canceled query | SELECT DISTINCT attrelid FROM pg_attribute WHERE attacl IS NOT NULL application_name | pg_dump -- Justin
