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Comment by LeafStorm | Hacker News Reader

Honestly, so far none of these have been the major performance bottleneck on my Macbook. For me, it's been RAM. Even though I have 4 GB of RAM, I have at least 3 GB wired or active at any given time - Chrome alone takes up roughly 1 GB of it, with all its helper processes. But unfortunately I really have no idea how to bring my RAM usage down.

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You don't really want to bring your RAM usage down. Unused RAM is a performance hit. Sure, some applications are hogs and that can result in a performance hit for background processes and task switching, but high RAM utilization is GOOD for performance, not bad.

High RAM utilization is only good when your RAM is topped off with cache and buffer use. It's bad when it's all consumed by program data that forces the OS to swap other running application stuff to disk, especially if you're using several programs at once.

why would all the memory of chrome be in RAM and other programs not? I suppose there must be lots of swapped data there too. Doesn't crome have a separate sub? process for each tab with not much shared between tabs?

In looking for ways to free disk space on my SSD I find that the chrome ~Library/Cache can grow to insane proportions (5G?)

I had the same issue until I upgraded to 8 GB. I'd recommend to anybody to go for 8GB directly. For me (or any other heavy user), 4GB is just not enough to run MacOS X (the 'kernel_task' alone takes >500MB).

I just upgraded to 16 gigs and it's amazing. The time for a suspend and restore of a parallels virtual instance went down by a large factor; it's now just 10 seconds to restore and 5 seconds to suspend with 2 gigs allocated to it.

I wanted to pipe in to say the same thing. For the longest time, I thought my Late 2008 15" MBP couldn't handle 8GB (chipset issue, I though). I figured 6GB was the largest, and I just stayed with the 4GB as it came from the factory. Then one day late last year, I realized that a) the Late 2008 15" MBP can take 8GB and b) 8GB of RAM was now VERY affordable.

It made a huge difference. No more constant thrashing of the HDD as it tries to manage a large swap file.

And here's a link with some evidence for 8GB in that MacBook Pro, for posterity: http://blog.macsales.com/9102-secret-firmware-lets-late-08-m...

Agreed, particularly on my MacBook Air where ~1GB is reserved for the shared video memory. I have to close Firefox or Chrome if I want to do any development work (our research compiler is a bit of a memory hog) without having a process get swapped out.

I would offer ridiculous gobs of money to upgrade to even 6GB.

Where did you get your ~1GB number? It's 384 megabytes on machines with 4GB, probably 256 on 2GB.

(If you have 13.3" MBP with 8GB of RAM, it carves out 512 MB for video memory.)

Maybe he has the 27" screen attached.

Yup, I connect to an external monitor. And worse, it doesn't seem to give that memory back without rebooting.

Sorry --- that was an important detail that I should have included.

"Even though I have 40 employees, I have at least 30 employees working at any given time."

My system starts to swap as it gets down to the last ~20% of its memory.

I had the same issue, and seriously: buy more RAM. A 2x4G kit from Crucial cost me $45 shipped.

And it's not much more of a financial leap to get to 16gb in a MacBook. 16.

I did not know some models were capable of supporting 16gb of RAM. Unfortunately, I don't think I have one of those models (I think I got mine in 2009). This is good to know, though.

The 2009 will support 6 or 8, depending on model. It is worth it.

Yeah I have 8 in a mid-2009 model, but I'm trying to sell it so that I can put it towards whatever Apple releases in the next few months. If I do sell it, I'll be torn between a MBA or a MBP.

I didn't know either, I'm actually not sure if 16 is officially supported, since Apple said my Macbook was only capable of 8. Crucial has a tool you can download to check compatibility with their various products and your specific macbook model.

Only specific, later generation models of Apple laptops can use 16 GB of RAM. It is NOT officially supported, but it works. The thermal profile likely hasn't been certified by Apple to the point they are comfortable supporting it, but it works at the electrical and logic signal levels.

sadly, can't upgrade the ram in the newer MBAs. this is the main reason i didn't keep mine (even though i wanted to)...VM + IDE + lots of browser instances open turned out to be kinda painful.

This.

I don't have a MacBook, but upgrading 4 Gb to 16 Gb in my iMac made a huge difference.

I hear you. I have a 2008 IMac and I wish i could put 8GB or more in it.

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