Solved: How can I calculate the routers'usage of memory?

greensubmarine2009 · ‎06-07-2009

How can I calculate the routers'usage of memory?

Example:

I entered "show proce mem" in the router,then ,

Router2821#show processes memory

Processor Pool Total: 213654736 Used: 9967864 Free: 203686872

I/O Pool Total: 10485760 Used: 2547456 Free: 7938304

What should I do next?

Giuseppe Larosa · ‎06-08-2009

Hello Hu,

memory can be seen as used by two parts:

main memory

I/O memory

you can see the total amount of memory in sh ver output.

In your show output we can see:

Used: 9967864 Free: 203686872 of main mem

Used: 2547456 Free: 7938304 of I/0 memory

total I/O memory should be:

2547456 + 7938304 = 10485760 10 MB

total main memory:

9967864 + 203686872 = 213654736 bytes

Hope to help

Giuseppe

View solution in original post

Giuseppe Larosa · ‎06-08-2009

Hello Hu,

your understanding is correct the I/O memory is used to handle packets received and to be transmitted on the router interfaces and to host the software queues that can be associated to the interfaces.

the main memory is where IOS code runs and where all the used tables are: ip routing table, CEF table, ARP table and so on.

Hope to help

Giuseppe

View solution in original post

Giuseppe Larosa · ‎06-08-2009

Hello Hu,

memory can be seen as used by two parts:

main memory

I/O memory

you can see the total amount of memory in sh ver output.

In your show output we can see:

Used: 9967864 Free: 203686872 of main mem

Used: 2547456 Free: 7938304 of I/0 memory

total I/O memory should be:

2547456 + 7938304 = 10485760 10 MB

total main memory:

9967864 + 203686872 = 213654736 bytes

Hope to help

Giuseppe

greensubmarine2009 · ‎06-08-2009

Thank you very much!

By the way, what does the I/O memory use for?

I think the main memory is a zone of memory where system's processes run,such as "ip input""exec line""DHCPD"etc.While the I/O memory is the I/O cache or other means?

Am I right?

Giuseppe Larosa · ‎06-08-2009

Hello Hu,

your understanding is correct the I/O memory is used to handle packets received and to be transmitted on the router interfaces and to host the software queues that can be associated to the interfaces.

the main memory is where IOS code runs and where all the used tables are: ip routing table, CEF table, ARP table and so on.

Hope to help

Giuseppe

greensubmarine2009 · ‎06-10-2009

This really helps!