Re: 2.4.28 -> ch..ch...changes....

Nix
2004-11-27T05:47:24Z

On 24 Nov 2004, Nick Warne mused:
> Normally memory slowly fills up, perhaps using swap for a bit under these
> circumstances - but looking afterwards:

This is a feature, not a bug. Free memory is wasted memory (although
some has to be kept free for drivers that need GFP_ATOMIC allocations:
i.e. `memory *now* dammit *now*'.

> root@linuxamd:~# free
> total used free shared buffers cached
> Mem: 1292348 520012 772336 0 38596 327304
> -/+ buffers/cache: 154112 1138236
> Swap: 1959888 0 1959888

The only thing I can think of that causes this is something very
memory-hungry that's just been killed, releasing a pile of pages back to
the system.

> But whatever, I am impressed indeed - somethings changed for the good!!!

I see no signs of such a change on my 2.4.28 boxes:

(UltraSPARC II)
total used free shared buffers cached
Mem: 509360 498432 10928 0 133568 52656
-/+ buffers/cache: 312208 197152
Swap: 1557264 143992 1413272

(Athlon IV)
total used free shared buffers cached
Mem: 775072 762744 12328 0 88304 322740
-/+ buffers/cache: 351700 423372
Swap: 1048560 81020 967540

(i586)
total used free shared buffers cached
Mem: 126992 123640 3352 0 11792 42012
-/+ buffers/cache: 69836 57156
Swap: 1245168 155560 1089608

The only suspiciously high free figure is on a 2.4.28 UML instance
(2.4.28 + forward-ported 2.4.27-1 patches) on one of those machines:

total used free shared buffers cached
Mem: 94000 66512 27488 0 2940 31260
-/+ buffers/cache: 32312 61688
Swap: 0 0 0

and that is trivially obviously caused by the instance's lack of swap :)

--
`The sword we forged has turned upon us
Only now, at the end of all things do we see
The lamp-bearer dies; only the lamp burns on.'