VM behaviour under 2.4.5-ac21
Hi,
just something positive for the weekend. With 2.4.5-ac21, the behaviour
on my laptop (128MB plus twice the sapw) seems a bit more sane. When I start new large applications now, the "used" portion of VM actually pushes against the cache instead of forcing stuff into swap. It is still using swap, but the effects on interactivity are much lighter.
So, if this is a preview of 2.4.6 bahaviour, there may be a light at
the end of the tunnel.
Have a good weekend
Martin
Signature · 5 lines
------------------------------------------------------------------ Martin Knoblauch | email: [email protected] TeraPort GmbH | Phone: +49-89-510857-309 C+ITS | Fax: +49-89-510857-111 http://www.teraport.de | Mobile: +49-170-4904759
Quoted 8 lines · On 20010629 Martin Knoblauch wrote:
Hi,
just something positive for the weekend. With 2.4.5-ac21, the behaviour on my laptop (128MB plus twice the sapw) seems a bit more sane. When I start new large applications now, the "used" portion of VM actually pushes against the cache instead of forcing stuff into swap. It is still using swap, but the effects on interactivity are much lighter.
I was just going to say the same. After ac20, I think, the kernel stopped pre-allocating swap.
Before I had always some swap used even if I was only using half my core memory (256Mb). And growing. I have not seen the box touch the swap since ac20. It uses all the ram it can get for cache, but does not send anything to swap to use its ram for cache.
Now running ac21 while building ac22, and state is:
werewolf:/usr/src# free
total used free shared buffers cached
Mem: 255588 241044 14544 2168 8836 153752
-/+ buffers/cache: 78456 177132
Swap: 152576 0 152576
werewolf:/usr/src# vmstat
procs memory swap io system cpu
r b w swpd free buff cache si so bi bo in cs us sy id
1 0 0 0 6944 8836 153868 0 0 16 12 95 385 17 3 80Signature · 4 lines
J.A. Magallon # Let the source be with you... mailto:[email protected] Mandrake Linux release 8.1 (Cooker) for i586 Linux werewolf 2.4.5-ac21 #1 SMP Fri Jun 29 16:02:22 CEST 2001 i686
Quoted 18 lines · J . A . Magallon
Quoted 8 lines · On 20010629 Martin Knoblauch wrote:
Hi,
just something positive for the weekend. With 2.4.5-ac21, the behaviour on my laptop (128MB plus twice the sapw) seems a bit more sane. When I start new large applications now, the "used" portion of VM actually pushes against the cache instead of forcing stuff into swap. It is still using swap, but the effects on interactivity are much lighter.
I was just going to say the same. After ac20, I think, the kernel stopped pre-allocating swap.
Before I had always some swap used even if I was only using half my core memory (256Mb). And growing. I have not seen the box touch the swap since ac20. It uses all the ram it can get for cache, but does not send anything to swap to use its ram for cache.
Now running ac21 while building ac22, and state is:
Quoted 10 lines
werewolf:/usr/src# free
total used free shared buffers cached
Mem: 255588 241044 14544 2168 8836 153752
-/+ buffers/cache: 78456 177132
Swap: 152576 0 152576
werewolf:/usr/src# vmstat
procs memory swap io system cpu
r b w swpd free buff cache si so bi bo in cs us sy id
1 0 0 0 6944 8836 153868 0 0 16 12 95 385 17 3 80Weird: there is no VM change between ac20 and 21.