[CALUG] Swap Size

[David A. Cafaro]

Depends on architecture apparently:

"How large can my swap space be?
Currently, the maximum size of a swap partition is architecture- 
dependent. For i386, m68k, ARM and PowerPC, it is "officially" 2Gb. It  
is 128Gb on alpha, 1Gb on sparc, and 3Tb on sparc64. An opteron on the  
2.6 kernel can write to a 16 Tb swap partition. For linux kernels 2.1  
and earlier, the limit is 128Mb. The partition may be larger than 128  
MB, but excess space is never used. If you want more than 128 MB of  
swap for a 2.1 and earlier kernel, you have to create multiple swap  
partitions (8 max). After 2.4, 32 swap areas are "officially"  
possible. See setting up swap for details.

footnote: "official" max swap size: With kernel 2.4, the limit is 64  
swap spaces at a maximum of 64Gb each, although this is not reflected  
in the man page for mkswap. With the 64 bit opteron on the 2.6 kernel,  
128 swap areas are permitted, each a whopping 16 Tb! (thanks to Peter  
Chubb for the calculation) "



The above is from:
http://tldp.org/HOWTO/Partition/requirements.html#SwapSize

So if you want you could have 128 16TB swap partitions, but only if  
you are running a 64bit os on 64bit hardware with a 2.6 kernel.  Oh  
and LOTS of free disk space ;-).

Cheers,
David


David A. Cafaro <dac at cafaro.net>
Cafaro's Ramblings:  www.cafaro.net



On Nov 7, 2008, at 4:47 PM, James Ewing Cottrell 3rd wrote:

> This is one of those bits of knowledge that one "knows" but can't
> remember where to go back to to cite the authority or recheck it in  
> case
> it has changed.
>
> In any case, I have heard that any swap size, either partition or  
> file,
> is limited to 2G. Is this still true? Where is this stated?
>
> JIM
>
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