Archiver log is saturating /tmp/

Until now archiver log was created on mhs machine under /tmp/ (default parameters)
However there is only 10 Gb available on this partition.
As a result after a month, the folder is saturated and causes the archiver to crash.

Firstly, do we want to keep those logs ? To be honest we haven't done it so far.
Secondly, is there different level of logging ? Because, currently the logfile size is growing really quickly, even quicker than the database itself.

For now, it's save locally under another partition(500GB), but we could also use our NFS mount.

Any thoughts ?