SWAP size

David Gilbert dgilbert at velocet.ca
Wed Apr 30 18:45:12 PDT 2003

>>>>> "Jin" == Jin Guojun <[DSD]" <j_guojun at lbl.gov>> writes:

Jin> not have a lot of RAM, though ...")  if (1) no money to buy more
Jin> RAM, (2) no slot to put more RAM or (3) it is a server just favor
Jin> by every user to run their programs.

Jin> Swap space is prepared for too many processes outrunning the RAM.
Jin> It is not for improving performance, but exchange cost of disk
Jin> for RAM.  More swap space required means that more swap time
Jin> means slow.

Another thing working in favour of 2x swap is that disk has been
becoming that much cheaper.  With 1G and 2G disks, I was carefully
considering the 256M of swap (2x 128M of memory) that I configured.
With disks of 80G and more, I have been putting 1G of swap on every
spindle I install because it really doesn't make a difference and I'd
rather have 4x 1G swap partitions spread across spindles than only one
4G partition.

That's not to claim that I have 2G of RAM (I actually have 1G), but
disk space in general has become amazingly cheap.


|David Gilbert, Velocet Communications.       | Two things can only be     |
|Mail:       dgilbert at velocet.net             |  equal if and only if they |
|http://daveg.ca                              |   are precisely opposite.  |

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