Hello, Log4j developers
We have a problem when debugging an online production system. Our
production system manages and distributes data across multiple worker
machines. There's a bug that can cause data unbalanced placement or even
unavailable under heavy work load. In this scenario, DEBUG level log will
help us a lot to diagnose the issue. However, we cannot always set logger's
level to DEBUG because that will store too many logs on disk and slow down
the production service, especially the bug just occurs occasionally.
I wonder if we could add a new type of memory appender in Log4j. This
appender will store log entries in a memory queue first, with a
configurable maximum queue size and a policy (like FIFO) to roll out stale
log entry once the queue is full. If any problem occurs, like some types of
exception we're interest is thrown, user can trigger the dump of this
appender to flush in memory logs into file for future diagnostic use. So it
can only record 'useful' DEBUG logs and related context in disk, avoid
wasting disk space and slowing down production service.
If you think it's worth doing, I can create a JIRA and paste my
prototype Pull Request for review.
Thanks,
Deshui
