4510 High CPU Utilization

[snbright]

We have two 4510's running native IOS with Sup V and they will be replacing two 5500's. We have noticed high cpu utilization on the 4510's with only about 12 users distributed between the two switches right now. We've been trying to find out with Cisco if this is normal for the 4510 but no definate answer yet. The 72 hour history shows an average of 20% with periodic spikes up to 99%. Does anyone know if this is normal for the 4510? And if so, how it's going to impact them when we move 500 users on.

Thanks...

Steve

[jv]

During high spikes of high CPU utilization can you please post a "show processes cpu sorted"

[Bobby Thekkekandam]

Hi Steve,

The 4500 series switches do have a higher overall CPU utilization than other platforms, and a 20-40% idle CPU utilization is considered normal. Here's a doc that explains it further:

http://www.cisco.com/en/US/products/hw/switches/ps663/products_tech_note09186a00804cef15.shtml

Now the spikes could be a problem depending on what process is causing it. Do you have any captures of show proc cpu when it was spiking?

HTH,

Bobby

*Please rate helpful posts

[snbright]

Thanks guys... We were just starting to look at that doc last Friday. Along with the 4510 normally running high CPU utilization, the first group of users we added were AppleTalk users and AppleTalk is software switched instead of hardware. And all software switching goes to the CPU. We did a capture of all CPU rx queues and didn't find anything unusual.