Re: [NTLK] [OT] Re: speed: OS X's fault

From: Bob Carls Dudney <kosmicdollop_at_saber.net>
Date: Sat Sep 26 2009 - 15:53:43 EDT

On 25/9/09, Steven Scotten wrote:
|
>thank you for explanation VM versus swap

Happy to share.

>terms often used interchangeably, I imagine because virtual memory
>made swapfiles possible

And for probably most purposes the distinction doesn't matter,
especially on user forums.

>It's RAID0

Oh, sorry, me forgot RAID can also be used for performance boost.
Thanks for explaining.

>G4 PB with 1.25GB of RAM, just turning on machine leaves 400+MB
>"green" or free according to Activity Monitor

Wow! You must have tons of extensions and/or apps loading on login.
As I recall it takes less than 400 MB to boot my machine. I'll
double-check next time I reboot, but I'm sure it's nowhere near 800.

> OS X has a number of things to do in RAM but preemptively uses swap
>to preserve free memory

On my PB, booting spits out 64 or 80 MB into one swapfile; I'm
curious how much your machine swaps on boot.

One thing's for sure, OS X is a memory guzzler horribilis. Very sorry
to hear Snow Cat no better re: RAM needs.

>How does swapping relate to "Page Ins", "Page Outs" and "Swap Used"
>reported in Activity Monitor?

"Outs" are memory swapped out to disk, "Ins" is swap memory being
copied back to RAM from disk, "Used" is total of swapfiles on disk.

>I have 360MB of Page Ins. Page Outs and Swap Used are both 0

I've seen people say to ignore paging faults; I know no reason to
doubt other stats, but there's clearly a contradiction between page
outs being 0 and "ins" being 360.

Currently Activity Monitor (AyM) says I have 1.2 G swap used, but
there are 1.5 G of swapfiles on disk. Perhaps .4 G of those files are
empty, or maybe AyM is wrong.

>It's my understanding OS X will use available RAM for a disk cache.
>I can use up 32GB of RAM running Photoshop while Photoshop itself
>only sees a fraction of that.

I presume that's inactive memory. Worst example I've seen how poorly
OS X manages VM. I presume that's same as or mostly heap L.W. Brown
said the OS never clears.

MemTools might be a big help. One can try free for a few days, cost < $12.

If I learn more useful ways to deal with these issues, I'll let ya'll
know. As mentioned, I'm back to the drawing board. And interested to
try method L.W. Brown noted, but looks like swapping isn't my main
headache -- at least it's a lot tamer with MemTools.

B

====================================================================
The NewtonTalk Mailing List - http://www.newtontalk.net/
The Official Newton FAQ - http://www.splorp.com/newton/faq/
The Newton Glossary - http://www.splorp.com/newton/glossary/
WikiWikiNewt - http://tools.unna.org/wikiwikinewt/
====================================================================
Received on Sat Sep 26 15:53:54 2009

This archive was generated by hypermail 2.1.8 : Sat Sep 26 2009 - 19:30:00 EDT