David Drummond wrote in a message to Roy J. Tellason:

 DD> The reason for two swap partitions is that the apparent maximum
 DD> size for a swap partition in Slackware 8 (and below) is 128Mb. I
 DD> wanted 256Mb swap space. 

I think that's dependent on kernel version,  and went away as a restriction
somewhere around 2.2.x,  though I'm not precisely sure about the version
number.  In any case,  with anything fairly recent the restriction just
isn't there any more.

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