Meaning of "dovecot: ssl-params: Error: epoll_ctl(del, 7) failed"?

Question

During dovecot regeneration of ssl-params I noticed this sequence in my log file:

Mar 13 10:37:37 mail dovecot: ssl-params: Generating SSL parameters
Mar 13 10:37:52 mail dovecot: ssl-params: Error: epoll_ctl(del, 7) failed: No such file or directory
Mar 13 10:37:55 mail dovecot: ssl-params: SSL parameters regeneration completed

What is the meaning of the epoll_ctl() error? I've done some google searches and have found no answers to help me sort out if I can safely ignore this error, if there's a problem or I have a configuration issue.

Thoughts?

Answer 1

My comments are based on an answer about dovecot generating ssl parameters.

The file /var/lib/dovecot/ssl-parameters.ssl (ssl-parameters.dat on CentOS 6) mentioned in the other answer is regenerated weekly. In my logs, this process takes from 5 sec to over a min. Overnight, my logs had these messages:

Dec 12 17:34:14 xxxx dovecot: ssl-params: Generating SSL parameters
Dec 12 17:34:23 xxxx dovecot: ssl-params: SSL parameters regeneration completed
Dec 12 17:34:24 xxxx dovecot: ssl-params: Error: epoll_ctl(del, 7) failed: No such file or directory

This morning, the time stamp on ssl-parameters.dat is 2015-12-12 17:34:23.

I think that:

1. regenerating the SSL parameters file is independent of whatever is checking for its existence
2. this error occurs when the SSL parameters file is accessed (for whatever reason) while it is being regenerated
3. although my error was logged after the regeneration completed, it likely occurred during the window when the file did not exist

This may represent a bug in dovecot. Perhaps this file could be replaced atomically or a locking mechanism added. That said, this error does not seem to manifest other than in the log.