Package: rsyslog Version: 8.4.2-1+deb8u2 Seems there is memory leak in handling of "failed" messages - those messages which were in the action queue when the action was suspended. More information can be seen in bug report opened at mainstream [1].
Confirmed this bug is not recognized on rsyslog version 8.23.0-2~bpo8+1 available in jessie backports repository. [1] https://github.com/rsyslog/rsyslog/issues/1585#issuecomment-305431203 Peter
