[Patch v3 7/7] add a new interface to show the memory usage of 1st kernel

[Vivek Goyal]

On Mon, Jul 28, 2014 at 04:20:06PM +0800, Baoquan He wrote:
> Recently people complained that they don't know how to decide how
> much disk size need be reserved for kdump. E.g there are lots of
> machines with different memory size, if the memory usage information
> of current system can be shown, that can help them to make an estimate
> how much storage space need be reserved.
> 
> In this patch, a new interface is added into makedumpfile. By the
> help of this, people can know the page number of memory in different
> use. The implementation is analyzing the "System Ram" and "kernel text"
> program segment of /proc/kcore excluding the crashkernel range, then
> calculating the page number of different kind per vmcoreinfo.
> 
> The print is like below:
> ->$ ./makedumpfile  --mem-usage  /proc/kcore
> Excluding unnecessary pages        : [100.0 %] |

I think above message is now unnecessary. In fact we are not excluding
any pages.

> 
> Page number of memory in different use
> --------------------------------------------------

Above is not required.


> TYPE		PAGES			EXCLUDABLE	DESCRIPTION

We probably should put dashes under these headers

TYPE		PAGES			EXCLUDABLE	DESCRIPTION
====		=====			==========	===========

> ZERO		0               	yes		Pages filled with zero
> CACHE		562006          	yes		Cache pages
> CACHE_PRIVATE	353502          	yes		Cache pages + private
> USER		225780          	yes		User process pages
> FREE		2761884         	yes		Free pages
> KERN_DATA	235873          	no		Dumpable kernel data

What's "Dumpable kernel data" ? Are we saying they are kernel pages which
can't be filtered?

Why not simply call them "kernel data" or "kernel pages" 


> 
> Total pages on system:	4139045

How about "Total number of pages".

Otherwise this output looks much better than previous version. Thanks for
the changes.

Vivek