headsup: swap_pager.c

[Poul-Henning Kamp]

In message <xzpel0568cn.fsf at dwp.des.no>, Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?=
 writes:
>"Poul-Henning Kamp" <phk at phk.freebsd.dk> writes:
>> The thing you overlook is that often when things gets paged out, the
>> system is short on memory and therefore more likely to not do anything
>> productive, whereas when things gets paged in, there are a better chance
>> of some other process being able to use the CPU time productively.
>> If we did predictive pageouts like some of the "serious" mainfram OS's
>> this would be less true.
>
>How hard would it be to get the kernel to write the pages "most likely
>to be swapped out" to swap in the idle loop, to save time if / when
>they actually need to be swapped out later?

I don't know :-)

Quite frankly, given the sizes of RAM we see these days, I think that
paging optimizations may be largely a thing of the past.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.