LTM CPU utilization Question
I have a question and maybe someone can help me understand CPU utilization. I have a pair 0f 6900's (HA Pair) running 10.2.0 1755, which are provisioned as nominal Because of this, the CPU is generally right around 10%. I believe the OS reserves 10% just for management, hence the reason why it's running around 10%. Every Sunday around 4AM, I see my CPU utilization on both my active and standby unit do the same thing. They spike around 20-40% utilization for about 15-20 minutes then go back to normal. At that same time, I do not see any increase in thoroughput ssl transactions or anything according to dashboard or any of the statistics.
It just appears to be just the CPU utilization and it only happens on sunday's at 4AM. . Being both units are doing the same thing at the same time, I don't think it's an issue with one box in particular.
Is there any jobs, crons or anything that run on these appliances out of the box that could cause the CPU to do this on a weekly basis? Or if not, I'm wondering if this could be related to patches or some multicast going on the network at that time every week. I'm not seeing anymore traffic through the unit, but could it be alot of chatter on the wire it's listening to?
A couple things to note. I do not have a default route due to all one armed load balancing. I keep it simple and let the network do the routing.
Also, I have a seperate fiber cable plugged into each unit directly (not through a switch) for synch traffic and mirroring persistence. I only allow the synch vlan over that link.
Both unit's CPU graphs are identical each week. I'm just curious what could cause this..
I would appreciate any feedback anyone may have or experience with this...