finding kernel memory usage

[Venki Rajesh]

Hi,

I want to know the memory used by kernel.
How can i find it ?
Does the 'Cached' filed in '/proc/meminfo' refers to kernel cache memory ?

Thanks,
Rajesh

[Lew Pitcher]

On January 23, 2013 07:58, in linux.admin.news, Venki Rajesh wrote:

> Hi,
>
> I want to know the memory used by kernel.
> How can i find it ?

/proc/meminfo mostly describes userspace memory; it has very little
information about the Kernel's memory usage. "Buffers" and "Cached" are
userspace memory blocks managed by the kernel for userspace performance
optimizations.

It might be that "Kernelstack" and "Pagetables" refer to kernel-reserved
memory; others should be able to answer that for you.

One way to gather more info than meminfo provides is to, just after your
system comes up, scan your dmesg for the kernel memory allocation and
deallocation messages. They look like
Memory: 1002808k/1038848k available (4702k kernel code, 35172k reserved,
2124k data, 664k init, 129544k highmem)
and
Freeing initrd memory: 12904k freed
Freeing unused kernel memory: 664k freed

> Does the 'Cached' filed in '/proc/meminfo' refers to kernel cache memory ?

It refers to the data cache that the kernel maintains in userspace memory.

HTH
--
Lew Pitcher
"In Skills, We Trust"