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I'm the happy owner of a MacBook Air 2011 model with a nice, speedy SSD.

Usually, I'm really happy about the snappiness of this thing, especially because of this SSD.

Right now, I'm untarring a .tar.bz2 archive containing a little over 300k files that are all shy of 1k in size.

The performance is abysmal. The unpacking started out quick, then started slowing down. Right now, it's unpacking files at a rate of about 5 or 6 per second, the fans are blazing, and the computer is super-unresponsive (Stack Exchange front page took about 30s to load).

This seems really strange to me, and the only culprits I can think of are either HFS+ or FileVault (this is an encrypted disk).

But I don't know how to fix it, if at all possible. This is not just going to take forever, it'll also drain the battery in no time.

Are there any fixes to this?

Thanks :)

UPDATE: After about five minutes, system responsiveness is so bad that display updates take seconds. The same file on my Ubuntu server takes 7 seconds to untar. I'm half an hour in and less than 1/10th of the amount of files are unpacked. This is unreal.

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Have you tried using other unarchiving utilities? Like bzip2 or The Unarchiver if you used Archive Utility. – user495470 Jan 23 '13 at 16:48
Thanks, Lauri, I was about to do exactly that (just a zip file) when OS X appeared with "Your startup disk is getting full" ;) Sorry for the bother! – DanielSmedegaardBuus Jan 23 '13 at 17:02
I'm betting the sluggishness of the UI was because OS X was trimming the swap file to make room for the new files I was writing. – DanielSmedegaardBuus Jan 23 '13 at 17:03

Hehe, my bad! It was a close-to-full partition. I emptied the trash, and speeds were blazing again :)


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