SWAP size

Rob MacGregor rob_macgregor at hotmail.com
Wed Apr 30 23:25:46 PDT 2003

>From: Terry Lambert <tlambert2 at mindspring.com>
>So it's grown from "as much swap as you feel you need" to "as much
>swap as you have RAM" to "1.5 times RAM" to "2x RAM".
>All in all, it's just a rule of thumb; however, there are some
>consequences to not following it, for each time things have
>changed, the consequences get more and more dire.  8-).
>This is why people don't give much creedence to the people who
>are trying to run without swap; we're willing to help them track
>down things that make it impossible, but we recognize that just
>because something's possible doesn't mean it's a good idea.

So you're suggesting that if I've got 16 GB of RAM I should have 32 GB of 
swap?  That's an entire hard disk *just* for swap (though from a performance 
viewpoint, that's not bad).  What about systems with even more RAM?

I agree that having nowhere to store crash dumps is a Bad Thing.  However 
there will be cases where that tradeoff is worth not having a swap device.  
In my own case at home I have a FreeBSD (4.8) system without any swap.  I 
run without swap because the "disk" is a CompactFlash device - using that 
for swap wouldn't be smart.

Then there's the issue of diskless systems where it's not possible to have 

  Please DO NOT send me ANY email directly unless it's a privacy issue.
       Reply-to mangled to assist those who don't read the above.
Rob  |  What part of "no" was it you didn't understand?

Overloaded with spam? With MSN 8, you can filter it out 

More information about the freebsd-performance mailing list