find out which memory pages are owned by kernel

Question

I can obtain a wonderful memory map of all processes with the Linux command

pmap $(ps -A | awk '{print $1}'|grep -v PID) | sort | grep \^0

It looks like

...
00007fd6dbf45000      4K rw---  /lib/libnss_compat-2.11.1.so 
00007fd6dbf46000   1524K r-x--  /lib/libc-2.11.1.so
00007fd6dc0c3000   2044K -----  /lib/libc-2.11.1.so  
...

All processes' memory maps are merged here. But I am missing the information where the kernel has its memory pages. Is there a similar tool for the "complete memory map"?

Possible duplicate http://stackoverflow.com/questions/20480608/how-is-kernel-virtual-memory-mapped-to-physical-memory — Peter Lundgren, Dec 17 '13 at 14:59

score 1 · Answer 1 · answered Mar 12 '14 at 18:07

1

Your command doesn't make much sense. The addresses reported by pmap for each process are only valid in theses processes own address space, i.e. in their virtual memory. They will kind of "overlap" while technically they correspond to different pages. Some of them won't be in RAM but on disk.

The pages owned by the kernel use are on the other hand stored on physical memory.

answered Mar 12 '14 at 18:07

jlliagre

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thanks. So how can I get an overview what is stored in physical memory? – Thorsten Staerk Mar 18 '14 at 11:24
`cat /proc/meminfo` will give you an physical memory usage overview. – jlliagre Mar 19 '14 at 16:23

score 0 · Answer 2 · answered Mar 12 '14 at 17:20

Better approach would be to use sysrq.

Run following and check your /var/log/messages.

# echo m > /proc/sysrq-trigger

This would give you zone wise memory dump. Checkout following url

https://www.kernel.org/doc/gorman/html/understand/understand005.html

find out which memory pages are owned by kernel

2 Answers2