Re: swapout selection change in pre1

Marcelo Tosatti
2001-01-13T07:41:52Z

On Sat, 13 Jan 2001, Linus Torvalds wrote:

> It's the other way around: it used to be _extremely_ unfair towards
> threads, because threads woul dget swapped out _much_ more that
> non-threads. The new "count only nr of mm's" actually fixes a real problem
> in this area: a process with hundreds of threads would just get swapped
> out _way_ too quickly (it used to be counted as "hundreds of VM's", even
> though it's obviously just one VM, and should be swapped out as such).

The point is: Should this VM with hundreds of threads be treaded as a VM
with one thread ?

With the old "per-task" selection scheme (before -prerelease), swap_cnt
used to avoid us from scanning a VM too much (if swap_cnt reached zero the
VM would not be scanned until all other VM's had been scanned).