Sometimes you need to know how long dedup takes.
Dedup (SIS) has its own log file in /etc/log/sis
This log file can be access via the web interface: http(s)://cluster-mgmt-ip/spi/node-name/etc/log/
You can browse to various log folders via http(s)://cluster-mgmt-ip/spi/
These log folders might also be interesting:
core dump files http(s)://cluster-mgmt-ip/spi/node-name/etc/crash/