LiveCD patch for low-memory systems (192K)

Alexandre Strube surak at
Sat Mar 8 07:20:33 UTC 2008

Hello John!

>  >  On Sat, Mar 01, 2008 at 04:15:22PM +0900, John McCabe-Dansted wrote:
>  >  > Hello, I have created a low-memory patch for the Ubuntu 7.10 LiveCD.
>  >  > This patch is based on compcache, see:
>  >  >
>  >  > I have tested this on a 180MB VM and a 120MB VM with only-ubiquity. It
>  >  > worked in both cases.

Quoting compcache's site, "Description

Compressing swap pages and keeping them in RAM provides more memory
space for applications. This is especially useful for swapless
embedded devices. Also, flash storage typically used in embedded
devices suffer from wear-leveling issues - so, its very useful if we
can avoid them using as swap device."

Explain me because I'm stupid:

if we have ram in the first place, why should we swapping and
compressing the swap back into ram again? I mean, if you can store the
swap in ram, is that you have space, so you didn't even need to swap,

>  PROS:
>  P1: Much faster
>    (zero latency and decompression can be 25% as fast as memcpy)
>  P2: No need for swap partition.

Up to when? There will be a moment when the space reserved for it will
finish, no?

>  CONS:
>  C1: Requires Memory.

Wasn't it EXACTLY for machines without enough ram for running ubuntu normally?

>  C3: Places more load on CPU

What is the regular use-case for low-memory machines? Well, its OLD
machines. And I mean, OLD. Like pentium 133 or so.

>  C3 is less important than P4 on new desktops as DualCore single HDD
>  machines are now the norm. However in my testing of LiveCD in VMs I

HA! In YOUR country. Please don't generalize.

Serious, if you have little ram, it's well possible that you have a
low cpu as well. So I don't get the point of this.

By the way, what does it mean the (192K) at the subject?

Alexandre Strube
surak at

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