I have an app running on rackspace cloud (ubuntu 10.04).  For some reason, over the last 3 nights, the memory has been spiking and then leveling off for about 7 hours before eventually falling off.  It seems to start at midnight and last through 7 am (ignore the times on the chart -- they're off by 4 hours).Looking through Munin chart, there doesn't seem to be any increased activity in mysql, and the ethernet traffic doesn't seem to be spiking at all during that time (which would seem to negate something like a bot or crawler).Which tools are available for linux to troubleshoot something like this?
How to track down memory spikes?
memory;monitoring;munin