More than one swap device ?

[Mathew BM LIM]

In article <1991Mar21.193820.752 at ssd.kodak.com>, weimer at garden.kodak.COM (Gary Weimer (588-0953)) writes:
|> 
|> In article <1991Mar21.132725 at anusf.anu.edu.au>, mbl900 at anusf.anu.edu.au
|> (Mathew BM LIM) writes:
|> |> I am the administrator of a soon to be installed Fujitsu VP2200 running
|> |> UXP (Fujitsu's SysVR4). I have been trying to plan our file system structure
|> |> and swap space allocation.
|> 
|> I don't know how universal it is, but SunOS (bsd derived) has swapon(8)
|> for adding swap space (If you don't have it, you don't need to know how
|> it works, so I won't explain it). If this is used, swaping is
|> interleaved (supposedly equally) between the devices.
|> 
|> weimer at ssd.kodak.com ( Gary Weimer )

Yes, I know about swapon(8), but just what does "interleaved (supposedly
equally)" mean? Does the kernel remember which device it used last time and
use the other one for the next page? Are the devices selected randomly so that
on average they are equally used? Or is one device used all the time
until it fills up then overflows to the next? My guess is that it is
implementation dependant, does anyone have any hard knowledge on this subject?

-- 
---
Mathew Lim, Unix Systems Programmer, ANU Supercomputer Facility, ANU, Australia.
Telephone : +61 6 249 2750	| ACSnet   : Mathew.BM.Lim at anu.oz
Fax       : +61 6 247 3425	| Internet : Mathew.BM.Lim at anu.edu.au