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Why is OS X memory management so terrible?
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It's a misbelief that inactive memory has been released. This misbelief is perpetuated by the simplified explanation of inactive memory that Apple released in its support documentation because the example uses a description that includes a recently quit application.
Inactive memory is still allocated. Whether or not memory is deemed inactive is based on reference counting. Inactive memory is checked to see if it's actually inactive before being freed; this is where a memory leak prevents inactive memory from being freed by telling the system that it's still active and not available for reallocation. Inactive memory is also the memory that is prioritized to be written to the swap file before the other types of memory and is more liking to be associated with paging, including page outs.
http://lists.apple.com/archives/Darwin-kernel/2008/May/msg00072.html
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well, in speaking with apple, looks like they still use pram. "zapping" is still something they do.
ctrl+cmd+P+R during initial boot before the bong. hold until you hear the second or third bong then release and boot normal.
Agree with OP
Having read the entire thread, I believe I have the same problem with OP and came to the same conclusion as to what the problem is (with caveat that I'm no techie).
I also must point the finger at Lion. I have only 2GB RAM on my MBP but used it for 2 years without any problems. I'm a light user (no games etc) with just mail, office apps and browsers. I used to always sleep my computer without problems (would go without shutting down for weeks).
Once upgraded to Lion, even when I hadn't yet upgraded the apps (therefore not fault of apps), and used my computer in exactly the same way, I started getting problems with full RAM and a chunk of Inactive RAM that does not seem to be released efficiently. My computer started running very slowly and the only way to solve it is to either close apps or do a purge. Often all I have open is mail, chrome, skype, calendar, word and excel. That's it. I used to be able to run all those plus others like photoshop with no problems.
When absolutely nothing else changed but upgrading to Lion caused the problem, it's probably fair to point the finger at the OS...
I still can't find a solution (and OP rightly said don't suggest upgrading hardware, downgrading OS as that just isn't helpful).
Having read the entire thread, I believe I have the same problem with OP and came to the same conclusion as to what the problem is (with caveat that I'm no techie).
I also must point the finger at Lion. I have only 2GB RAM on my MBP but used it for 2 years without any problems. I'm a light user (no games etc) with just mail, office apps and browsers. I used to always sleep my computer without problems (would go without shutting down for weeks).
Once upgraded to Lion, even when I hadn't yet upgraded the apps (therefore not fault of apps), and used my computer in exactly the same way, I started getting problems with full RAM and a chunk of Inactive RAM that does not seem to be released efficiently. My computer started running very slowly and the only way to solve it is to either close apps or do a purge. Often all I have open is mail, chrome, skype, calendar, word and excel. That's it. I used to be able to run all those plus others like photoshop with no problems.
When absolutely nothing else changed but upgrading to Lion caused the problem, it's probably fair to point the finger at the OS...
I still can't find a solution (and OP rightly said don't suggest upgrading hardware, downgrading OS as that just isn't helpful).
Well, here's my Activity Monitor after not shutting down my MBP for a day or three. Even when I have a game running, I get about 3GB of free memory. You guys are definitely running something that's leaking memory, since I have yet to experience the same problem.
http://imageshack.us/f/254/screenshot20111108at113.png/
To those who need a temporary solution, look for the FreeMemory app in the Mac App Store. You can then manually free up memory from your menu bar.
http://imageshack.us/f/254/screenshot20111108at113.png/
To those who need a temporary solution, look for the FreeMemory app in the Mac App Store. You can then manually free up memory from your menu bar.
Somthing i found a few years back is if you leave a screensaver on while your not using your macbook seems to free up as much memory as possible. Worked (possibly still does) on my Mid-2009 13" Macbook Pro running Snow Leopard.
I have a macbook pro 15 2010 i7 4GB, and I must say that Snow Leopard's memory management is terrible.
Once free memory gets down to less than 100mb (which is nearly always), except for times when I'm only browsing the web or watching a video, the machine gets terribly unresponsive. The pathetic part of all this is that I still have around 900mb of inactive memory (and I have Photoshop, Dreamweaver, and VMWare Fusion with WinXP open, with browsers, etc.)
You can say all you want about the OS swapping inactive memory when it finds it necessary; the true reality is that the machine is truly unresponsive and OSX's memory swapping is not fast.
A laptop at this pricepoint with 4GB shouldn't get slow at all when using Photoshop, Illustrator and Dreamweaver at the same time. It was intended to work fast, the truth is it doesn't.
Once free memory gets down to less than 100mb (which is nearly always), except for times when I'm only browsing the web or watching a video, the machine gets terribly unresponsive. The pathetic part of all this is that I still have around 900mb of inactive memory (and I have Photoshop, Dreamweaver, and VMWare Fusion with WinXP open, with browsers, etc.)
You can say all you want about the OS swapping inactive memory when it finds it necessary; the true reality is that the machine is truly unresponsive and OSX's memory swapping is not fast.
A laptop at this pricepoint with 4GB shouldn't get slow at all when using Photoshop, Illustrator and Dreamweaver at the same time. It was intended to work fast, the truth is it doesn't.
4GB where the heck is enough to run all those apps...?
Try upgrading to Mountain Lion and run the same amount of apps on that pathetic 4GB, it'll be even worse. Mountain Lion is even more resource hungry than Snow Leopard...
Maxed it out 8GB for god sake, memory is dirt cheap nowadays... Better still, plonk in an SSD... Now that's fast...
4GB where the heck is enough to run all those apps...?
Try upgrading to Mountain Lion and run the same amount of apps on that pathetic 4GB, it'll be even worse. Mountain Lion is even more resource hungry than Snow Leopard...
Maxed it out 8GB for god sake, memory is dirt cheap nowadays... Better still, plonk in an SSD... Now that's fast...
You're right, I still haven't because I'm planning on buying the 8GB/256SSD Macbook Air in January and I don't want to buy extra stuff for this one which I'll sell in 2 months.
And I agree, the 5400 HD is pathetically slow, a small PSD file always loads slow, I always get the impression that the machine is quite sluggish because of that drive. Did you notice a big difference when changing to SSD? I don't mean when opening applications (I know that's fast), but when browsing the finder, changing between 10 tabs in chrome, etc. Do clicks respond faster?
Nevertheless, I still don't get why the hell there are 900mb in inactive memory. That memory should get swapped quickly onto free memory.
At time of writing, my Activity Monitor registers an inactive memory of 1.08GB, by just browsing on Safari using 2 windows of 6 tabs each, with Chrome idle, iTunes idle, BOINC idle, and Adium running, no other major apps active... Slightly more than yours. There's no slowdown on my side, most probably I have 8GB and an SSD in case of a pageout.
Inactive memory is the OS X'es way of keeping active data within memory to allow quick access in case these data are being called to use. Practically harmless. In short, inactive memory IMO is always better than free memory.
Sadly (but not unfortunately) Snow Leopard does not support Purge command on Terminal. Otherwise you can manually free up inactive memory that way...
Thanks for your reply.
By the way, Snow Leopard does support Purge, you have to install the Code..something that comes with the dvd.
I've used it a number of times but it doesn't make a big difference because in no time you'll see that inactive memory fills up again.
The slowdown on my side comes when free memory gets under 50mb, even if I have 900/1gb of inactive memory.