Memory and Os 10.2

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Okay, so my iBook was sorta sluggish with 256mb of ram in Jaguar. I then added 256mb of ram, for a total of 384. Now when i run TOP in the terminal...when I first bootup i'm fine, but then after about a day of use...the ram gets as low as 4mb of free memory remaining and most of it in inactive memory. At this point i run vm_stat 5 and look for pageouts....and then it starts happening @about 4mb of free memory left, more and more pageouts....The problem here is, I can close all the programs i'm running and most of the memory never gets released from the inactive memory section....why is this? Is there some sort of wierd memory problem in 10.2 that they need to fix? Anyone else having similiar problems? I mean, i'm all up for getting a 512mb dim and have 640mb of ram, but that isn't the point really, the point is that the memory just isn't being used properly.
 
update on this topic....apparently, once i get to about 4mb of free ram availible....and start opening mroe and more apps....it starts using some of that inactive ram....and then if i close all those apps, i start getting more fre ram availible...so i guess it's memory management is just sorta wierding me out or something, when it does page out i dont' really notice a performance decrease or anything, so I guess it's not something to sweat over or anything....hmm, but still....any more info on this problem would be good, or a breakdown on how the memory management works in 10.2. :)
 
I've noticed the same phenomenon. I'm running a flat screen iMac with 512 mb. Under OS X v 10.1.x I never had a pageout, even when I had many applications open at once. Now I get pageouts and 'top' also tells me that my available memory is low. But like you I don't see any degradation in performance, even when the machine is paging memory out, and I think I'm able to run the same number of applications simultaneously. Last night, for example, I launched Word, IE, Mozilla, iTunes, Mail, and Terminal and the machine didn't even hiccup. I've noticed that there are a few more background processes running under Jaguar, i.e., the iChat client, but this alone shouldn't explain the memory usage we're seeing.
 
THANK YOU JEBUS! someone else has the same problem. Well, i'm glad i'm not the only one on this boat. It's wierd, but I guess i'll ride it through and wait until the next update or what not, they will probably fix this bug...maybe it's just reading the memory usage wrong or they changed the way the memory is managed...not sure, but whatever it is, it's annoying =/
 
Okay, well....I've been screwing around trying to see why I'm getting so many more pageouts with 10.2....and I'm not exactly sure if it's some software problem. I'm thinking it could possibly be iChat that has some sort of serious memory leak. That is the only program that I run 24/7....I'll update you guys soon if I find what is causing the system to run very low on free memory.
 
I've been having some serious lag since I've updated to 10.2, especially in photoshop. All of my friends have been saying how amazingly fast it is, and they all have dual processors, so I though I was out of luck. But I just bought 512 of more memory and now it screams. Photoshop is way way faster, and my games like medal of honor and wolfenstien were always fast, but some of the bigger levels would lag a bit during big gun fights, but now even those big levels are as smooth as butter. I can't get over it. You wouldn't think you'd need 768mb of ram to run an os properly, but I think apple will get it going more efficiently. But for now, I'd say to everyone get more ram, and you will be very happy.
 
okay, well i think the problem lies partially in the 256mb so dimm i put in there from infeneon....I put back in the 128mb micron from apple and i get a lot less page outs.....very few actually. I don't really have enough cash to buy a 512mb modeule from Apple though. I'm wondering what kind of ram you people buy for your macs. I was looking into a 512mb crucial dimm that I could get straight from crucial for my iBook for $220 or so. I figure since crucial is an offshoot of micron that it should work correctly, they say it should work fine. What do you all recommend in terms of memory besides the super marked up crap that apple sells.
 
I just got my 512 for $69 at macsolutions.com. I wasn't going to buy that much, but when I saw it for that price, I couldn't restist. Anyway, I haven't seen a better deal, and it seems to be great ram. Works flawlessly. Apple's ram might be a little better, but for $400 I'll take my chances. I mean, you can buy half of a new computer with that. Sorry Apple.
 
i got a 512 pc 133 cl3 so-dimm for $107 from my pc store, w00p...seems to work fine. Hehe...and A lot more memory leaves less room for pageouts. :) I still think osx needs some fine tuning to the memory management system.
 
Problem with the memory management system? Where?

Ok, actually there are some memory issues, but they really aren't from what you think. OS X just requires alot of memory. Personally I think 1G is a good number. In all honesty, on a G4 and above box, it's really not very expensive to hit 1G, atleast use 512M as a mininum. One of the biggest issues that can cause lots of page in and outs if you have a lower amount of memory is having multiple applications open.

Ofcourse, this isn't for the reason you think. You'd think "lots of apps, means lots of memory, so you'd page alot". Well, that is kinda true, but only when you're switching apps. One of the big issues is the window manager in OS X. The more apps you have running, the more memory it sucks down. This memory also likes to be in physical ram, doesn't swap very well. The reason for this is, due to all the cool effects/transparencies/etc in Quartz, Quartz keeps every window drawn completely in memory. If it's hidden, it's still drawn completely in memory. If you have 10 differnt IE windows open, it has every pixel of every window sitting in memory. When you pull one of the background windows forward, it gets to access all that memory to compute what gets shown, what needs to be transparent, where shadows fall, etc. If your having to send window manager memory to swap to run you app, you're gonna get alot of page outs when you start moving windows. This becomes even worse when you switch between 2 open apps, not only are those two apps fighting for memory, but the window manager is fighting for memory inbetween the switch. In all theory, with todays memory prices, if you have to swap, you need to buy more RAM, that or run less programs :) For example, we can look at my current memory usage (just looking at the top proccesses):

XDarwin: 177M
Mozilla: 72M
iCal: 61M
Window Manager: 138M

Thats 448M of RAM without adding in any of the other things that the OS uses in the backend. If I had 256M, and I kept switching between XDarwin and Mozilla, I'd be hosed for speed. Even with 512 adding in all the needed backend memory, I'd still be swapping up a storm.

Ofcourse, you can blame apple for this, but then we wouldnt' have our pretty eye candy window manager. You could also blame the app developers for making bloated apps, but people tend to like the bloat. You could blame the memory management system, but it's not it's fault that it's having to manage applications that are complete hogs. Ofcourse, you could also blame the economy for being in the toilet and not allowing you to buy more RAM :) Or, just be like the rest of the world, and blame me, thats what I'm here for :)

Ofcourse, this is just my $.02 worth, actually, I think I made it up to a nickel tonight.

Brian
 
See...I would have no problem buying a gb of ram, but my iBook tops at 640mb, hehe. Regardless, I do think they should redo how osx takes care of the drawing windows and keeping them in memory, that seems to be the biggest waste of memory. This is probably not easily done and since I don't program I wouldn't understand what it would take to make memory usage be a little bit more on the efficient side. Anyhow, your post was very informative and I appreciate the response and and end to my memory questions. 640mb should be plenty for what I do with this laptop and I shouldn't be bitching anymore about pageouts...at least until the next time iBitch about page outs...hmm..nevermind, I think i've been drinking too much coffee :p
 
You could start taking the drawn windows out of memory, but you really don't want to. One reason is you'll use alot of cpu cycles when you raise windows as the os now has to calculate and draw the window again to stick into memory, to then show to the screen. If you haven't noticed, OS X doesn't have those issues that you get with windows with half drawn windows, or windows showing with no data in the middle, and the like. This is because the window is all stored in memory and not drawn on the fly. Also, by taking the fully drawn windows out of memory, you kill the functions needed by Quartz Extreme to do it's magic. Quartz Extreme treats every window on the screen as a texture in OpenGL. The video card needs to be able to pull that "texture" out of memory whenever it needs it. You really don't want to have to create your "texture" with CPU cycles when your video card is asking for it. That would basically kill the point of using OpenGL as the compositing engine for Quartz.

Ofcourse, all this means diddly for folks that don't have Quartz Extreme capable machines, and max out at lower amounts of memory (ofcourse 640M is plenty for 99% of folks, I'm just a power user). But ofcourse, you really don't want Apple stopping innovation in order to make everyone happy. I think they have a pretty good medium for old users and the future. Personally I feel the biggest problem Microsoft has with Windows is they are afraid to make fundemental changes to their OS that need to be made, as it will cause issues with older computers, and older software. But this transition must be done. But, this is getting onto a completely different track :)

Brian
 
A slight clarification:

Jaguar adds compression to the window bitmaps to decrease memory usage, this is true for Quartz _and_ QuartzGL (ok, ok, Quartz Extreme... feh). So in that sense, it's not "every single pixel" in every window. (Although, in 10.0 - 10.1.5......)

-alex
 
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