[CS-FSLUG] Macs and Memory

[Nathan T.]

On 18-Dec-06, at 8:22 PM, Timothy Butler wrote:

[snip]

> How much is inactive?

Actually quite a bit after it's been on for a while. We just had a  
power outage a few hours ago (glad I have a UPS) so I shut down the  
Mac, and after a cold boot I've got over 600MB of free RAM. What I  
don't get is how much becomes "inactive" after it's only been on for  
a few hours. I'm assuming that "inactive" memory is what is being  
used by a program that isn't currently being used, but even after I  
close off all the applications I opened a lot of inactive memory is  
still being used.

> Mine only shows about 200 megs free (though
> admittedly I have a ton of stuff open). I can't say I've watched it
> that closely, but back in my Linux desktop days, part of the ram was
> used for cache when it wasn't otherwise needed. The inactive number
> was more telling, IIRC, than the used number.
>
> 	OS X will run on 256 megs of ram, so if you have a gig, the OS
> shouldn't be filling it up (for that matter, up until Tiger, it would
> run on 128 megs).

I suppose being new the the Mac platform I'm making a lot of  
incorrect assumptions, I suppose the lack of a dual core processor  
could be the bottleneck because when I look at page ins/outs there  
are usually 0 outs. If I'm not mistaken that means that inactive  
programs are being cached to disk, but nothing is being pulled back  
out into active memory.

>> I'd like some comments on what to do about this, if I upgrade the ram
>> to 2GB would it be worth the large investment (1GB cost me ~$250CAD).
>> Or should I simply wait and get a more powerful core Duo Mini with
>> 2GB of ram some time next year? If I get a new one should I really
>> save up and get something with 4GB of ram?
>
> 	I'm not sure what your goals are, but I'd probably wait and get a
> Core 2 Duo Mac mini, which supposedly (so say the rumormongers) will
> show up at MacWorld in January.

I think that's sound advice, I'm more and more convinced that while  
the processor is adequate and the memory is adequate, the lack of a  
better multithreading support is what's causing the apparent lack of  
speed. That said I was also hoping that the drivers would  
substantially improve with Leopard and that I would get better  
performance with that. I think what I'll do is save up and plan for  
an upgrade in summer 2007 after leopard is released.

>> Oh, and could anyone tell me how big of a difference there is on a
>> Mac when it has a independent video card as compared to an integrated
>> one?
>
> 	From everything I've been reading, the integrated video in the Mac
> mini and MacBook seems to be performing quite well except for really
> intense graphical needs. I think the Intel Extreme chipsets going in
> the Macs is suppose to perform similarly well to how it does under
> Windows (which is quite good).  Better, supposedly, than the oldish
> ATI discrete video card in the old PPC Mac minis.
>
> 	If you are going to demand a lot of Open GL performance for 3D,
> etc., however, you'll find the discrete cards better. It's really a
> matter of needs on the Mac just like any other PC. Integrated cards
> seem to be good enough for most these days, and they are only getting
> better.

Perhaps I'm used to being a little spoilt by affordable PC hardware,  
right now my main desktop computer has 2GB of ram and a 256MB NVidia  
GeForce FX 7600 video card, it's probably unfair to expect my Mac  
Mini to compare to that.