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Something is deeply broken in OS X memory management

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Re: Something is deeply broken in OS X memory management

#12

Earlier quoted context omitted.

The thing is, Lion runs like crap without an SSD or insane amounts of RAM for many people. It doesn't help if it works for some, or even the majority. If anything, we need more people digging in OS X internals. I am sorry to use a tired analogy here, but Vista did work great for many too. I have two Macs, one brand new, one migrated from SL, and 10.7 Safari was almost unusable on both until I installed SSDs. If that…

I upgraded to an SSD while on Leopard, and was amazed at the speed. Snow Leopard continued to impress. Lion slowed things down terribly (even with the SSD!), but I have good news: ever since Mountain Lion DP2, it's been fast again.

Yes, I am a fan of ML so far too.

Given that Apple has fixed none of my reported bugs in 10.7, but I can't reproduce many of them in 10.8, I wonder if it even makes sense to analyze 10.7 anymore - seems it's a done deal for Apple.

Re: Something is deeply broken in OS X memory management

#13
post #2

You can run `purge` in a terminal to free your 'inactive' ram. I've set up a cron job to purge frequently, keeps thing humming.

Can you explain a bit more how this works?

The `purge` command has a pretty short man page:

> purge -- force disk cache to be purged (flushed and emptied)

> Purge can be used to approximate initial boot conditions with a cold disk buffer cache for performance analysis. It does not affect anonymous memory that has been allocated through malloc, vm_allocate, etc.

[This seems to talk about it more: http://workstuff.tumblr.com/post/19036310553/two-things-that...

On my 10.5 laptop it didn't seem to dramatically decrease the memory marked "inactive".]

Re: Something is deeply broken in OS X memory management

#14

Does anyone else notice extreme time-based slowdowns using multiple monitors? I've looked through forums and system logs and I can't find an immediate explanation for it. The system tends to hang when using multiple monitors for any extended period of time.

Yes, but I'm using weaker hardware (2009 Mini w/ 2.2GHz Core 2 Duo) on two Samsung panels @ 2048x1152 each. It's improved and doesn't completely hang since I bumped it to 8Gigs of RAM, but there is still a noticeable amount of lag at times. Goes away completely on one panel. Not sure which chunk of the hardware or OS I'd blame first, as I'm hitting the limits of most everything. Little box wasn't bought (or intended) for what I'm using it for.

Re: Something is deeply broken in OS X memory management

#18
post #6

No actual data, barely any technical discussion at all, mention of "the garbage collection algorithm" which most likely isn't even being used by most of the apps running, capped by a total cargo-cult solution... and this is #1 on the front page?

The post is (too) light on information, but I don't dismiss it immediately. Perry Metzger was very much involved with NetBSD (maybe he still is) as a developer. He might know a thing or two about memory management ;).

Re: Something is deeply broken in OS X memory management

#20
post #6

No actual data, barely any technical discussion at all, mention of "the garbage collection algorithm" which most likely isn't even being used by most of the apps running, capped by a total cargo-cult solution... and this is #1 on the front page?

Probably a lot of people hitting the up arrow to save the link to try out this evening. I plead guilty to doing that. I wish I'd read the comments first.
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