Re: [PATCH 1/7] ksm: add some comments

[Hugh Dickins]

On Fri, 22 Feb 2013, Ric Mason wrote:
> 
> What's the root reason merge_across_nodes setting just can be changed only
> when there are no ksm shared pages in system?

Simplicity.  Why add code (moving nodes from tree to tree, handling
the collisions) for a rare case that doesn't need to be fast?

> Can they be unmerged and merged again during ksmd scan?

That's more or less what happens, isn't it?  Perhaps you're
asking why the admin has to echo 2 >run; echo 0 >merge; echo 1 >run
instead of that all happening automatically inside the echo 0 > merge?

If I'd implemented it myself, I might have chosen to do it that way;
but neither I nor other reviewers felt strongly enough to change that,
though we could do so.

Hugh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/