I'm planning to upgrade my RAM in the next week or so. I currently have 8GB (2 x 4GB) DDR3 1333Mhz RAM installed. I'm planning to upgrade to 16GB (2 x 8GB) DDR3 1600Mhz RAM. This would be the second time I updated the RAM (from stock 2 x 2GB DDR3 1333).

The Latency is also higher with the 16GB of RAM. Since latency is time, the higher it is the slower - albeit largely immeasurable.



I'm trying to bring down the page out & in's and leave enough room for other services to function comfortably. I'd love to upgrade from my Quad-Core but it's not likely going to happen in the next few years, so I'm resorting to RAM upgrades. I understand the Swap is the size of the RAM, so I can't lower that. It's hard to ask for a real world idea of any improvements but would this upgrade at least suppress page-outs?

The most intensive process has got to be, at times, my minecraft game server. Which, as of now is using 396 of 1011MB's allotted to it. Every now and again I'll start up a 3D Landscape generator, and various image & video manipulation programs.

I don't run any real server processes despite the Server status of the OS in the image. I went with the Mini Server for the dual drives & Quad CPU. Which, I haven't regretted (other than Apple is stubborn when it comes to choices, because I would have preferred to not of had OS X Server). I do plan on an SSD but that'll come later rather than sooner.

You can lower the amount of swap used by increasing RAM, and this will lower the paging, even though the swapfile itself will have to grow.

http://support.apple.com/kb/HT1342
https://developer.apple.com/library/mac/#documentation/Performance/Conceptual/ManagingMemory/Articles/AboutMemory.html

p.s. As an ancillary note, make sure you have enough disk space to deal with the increased size of the sleepimage file and the swapfile to correspond with the increase in RAM.

p.p.s., you can use the purge command to clear the in-RAM cache of recently used data for closed Applications to do more advanced profiling, or to free it all at once (some games are happier loading if all of the space they need is free, rather than a mix of free and inactive).

I've seen the support topic earlier while looking up some information but it didn't answer all of it.

I'll try the purge command daily to see if that helps. The RAM I linked above isn't available locally at the moment so I have some time.

I'll read through the developer page in a short while.

Wait Mac OS X forces both the hibernate file and swapfiles to be equal to ram? Linux has long been smart enough to deal with hibernating to a swap that is less than the total ram. For hibernate modern processors can gzip or similar faster than most disks can handle plus the fact that much of your "used" ram is actually cache or similar and thus can be dumped before suspending. And swap being equal to ram just seems useless, I always understood that as a guideline rather than a forced rule and see no reason it would/should be forced.

Also while more ram may help things I'm not sure what other than the minecraft server would possibly need this. Sure it may be nice, but I'm not convinced the ROI is there for you.

Well, the minecraft server will stay at 1GB of RAM (1011MB to be exact), so the server wouldn't benefit. The other 15GB's will be for the OS and other applications that require it. But maybe I'll just upgrade to 8GB of 1600 RAM rather than 16GB of 1600. I'm giving myself until I download & install OS X 10.8 so I can have my computer on as uninterrupted as possible.

But more than anything, I'm trying to limit my page outs than anything else. I'll try cron-jobbing the purge RAM command daily (half daily) and monitor my page-outs until I restart my computer for updates & a potential hardware upgrade.

Since the topic started, I'm at 29.85 Page Outs, 139.93 Page Ins and 9.04GB of Swap. Not sure how normal that is but I'd like it to be as small as possible between monthly restarts.

(I'm definitely not tunnel visioned on the corsair vengeance, as I prefer to by locally on this. So whatever goes on sale this weekend at Fry's or possibly Best Buy I'll likely pick up. Sadly, neither of them have the RAM listed above in-store.)

Check out OWC if you're buying for Mac.

Jonimus: It may actually only be the sleepimage that is that large, swap may be dynamically sized. I know Windows isn't that smart and tries to force it on you though, so I may have that in mind from my dual booting situation.