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Curious to know: does using a RAM disk in the Mac OS X operating system make sense in terms of performance and speed?

for more context: I was thinking of moving my Browser's Cache folder (Google Chrome) to this newly created RAM disk. This is considered to increase surfing speeds by 20% in Windows, just want to know if the same applies to Mac OS X).

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Just do it and see for yourself? Of course, one unfortunate side effect would be the clearing of the cache whenever you turn off your machine. – Daniel Beck Dec 6 '10 at 11:24
@Daniel: actually i wouldn't call the cache clearing part unfortunate. it's apparently more secure, but yeah i get what you're saying, the whole re-loading part. – Kaushik Gopal Dec 8 '10 at 5:03

According to this Mozilla Knowledge Base Article Firefox already does (or can) cache images in memory. The gist of it:

This preference controls the maximum amount of memory to use for caching decoded images and chrome (application user interface elements).

I wonder if the claimed 20% is the result of testing the technique, or just "There! - that otta fly." You could be the one to do the science. But consider: A RAM disk takes memory from all tasks including the OS. Firefox's RAM caching only takes the memory FF needs, while it needs it. It might be fun and instructive to plan a test and run it though. I hope you'll report back if you do it.

Edit: I missed that the OP asked about Chrome, as Daniel Beck points out. I'm leaving the answer up for the comments about RAM disks (grawity's counter-example notwithstanding. But thanks for the tip, grawity - I hadn't known that). Also anyone searching for similar information about Firefox someday.

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He's using Google Chrome, so, while interesting, this doesn't answer his question. Or maybe you can find something similar for Chrome? – Daniel Beck Dec 6 '10 at 11:30
Not all RAM disk implementations use memory permanently: Linux tmpfs, for example, only occupies what it needs. (It is a filesystem, not a real "disk" emulation, however - which is where the advantage lies.) – grawity Dec 6 '10 at 20:44
Daniel Beck: Oops, missed that. Serves me right for posting before coffee. – JRobert Dec 6 '10 at 22:53
I would be surprised if any modern browser didn't cache things in memory on its own, without the help of a RAM disk. – Ryan Thompson Mar 13 '11 at 9:27

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