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typoon · Jan 10, 2001, 09:56 PM

Is there any ill effects of lower the disk cache in the memory control panels? Will it slow performance? I ran a test doesn't seem that much slower. I set it to 1024 and rebooted and from the Chime to having the control strip appear it was 1 min 26 sec and I go the same time when I had it set to the default of 8160. I know that when lowering it the finder seems to use less memory. Wouldn't that be a good thing?

rjenkinson · Jan 10, 2001, 10:09 PM

i don't think changing the size of the disk cache would have much of an effect on the time it takes to reboot the machine. once the machine is up and running, the disk cache is used for frequently accessed data (icons, etc.)... that's where you'd see any performance hit.

-r.

[This message has been edited by rjenkinson (edited 01-10-2001).]

Cipher13 · Jan 10, 2001, 10:46 PM

He's right, during normal ops it will seem slower.
How much RAM do you have?
Keep it set to default if you wanna conserve memory and get good performance.

Cipher13

typoon · Jan 10, 2001, 10:59 PM

I have 256 Megs of RAM on my Pismo and 768 on my G4

Cipher13 · Jan 11, 2001, 05:57 AM

Keep it at 8160

ESPECIALLY on the 768 machine!!

Cipher13

Gregory · Jan 11, 2001, 07:21 AM

Ah with 768 you might want to try 16 or 32MB for that disk cache. IE5 never hits the disk for its cache.waf so it's like having a RAM Disk w/ all the benefits and none of the problems.

Greg

typoon · Jan 11, 2001, 07:43 AM

What about with 256 Megs of RAM? Would I see that big of a performance hit? or should I just experiment and see if it feels slow?

MickS · Jan 11, 2001, 08:33 AM

:-(

My Pismo with 256MB of memory won't let me set it to above 8160.

typoon · Jan 11, 2001, 04:21 PM

Mick You need to Click on Custom and it should allow you to go past that. I have 256 Metgs of RAM and just tried it and it allows me to go past it

rjenkinson · Jan 11, 2001, 04:51 PM

i remember reading somewhere that the general rule of thumb for setting the disk cache is 32Kb per 1MB of RAM. i suppose if you've got tons of RAM you can set it as high as you like, but it may not actually improve performance past a certain setting.

-r.

typoon · Jan 11, 2001, 05:33 PM

I also remember reading somewhere that on a PPC it should be set to 1024 because that was the most efficient. In one of them fancy books I read that in.

giantmike · Jan 11, 2001, 06:23 PM

Actually, setting your cache depends on what kind of things you are doing with your Mac. If you are doing heavy graphics work, or playing games, keep it low (I keep mine at 2 MB with 288MB RAM). Those kinds of applications hate high disk caches, and it actually slows them down. If you aren't doing those things, you could set it higher and possibly see a speed increase, but everything I have read has told me that disk chaches about 4MB do nothing, and usualy slow the machine down.

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Cipher13 · Jan 11, 2001, 06:37 PM

Since when can you go above 8160?
Is that an OS 9.1 thing?
I just took it to 32 megs on mine - never knew it could go there

I saw keep it at around 16 max - the larger it is the slower it is to find stuff

Cipher13

typoon · Jan 11, 2001, 07:12 PM

Mine just set the default Disk Cache to 8160 on all my machine whether in 9.04 or in 9.1 or in 8.6 dunno why. Thanks for your help I thiknk I will lower it

typoon · Jan 11, 2001, 07:29 PM

Dunno I was able to do it under 9.1 could it be that I have I have 256 Megs of RAM? I was able to do it in 9.1 though misunderstood you in th above post

typoon · Jan 11, 2001, 07:35 PM

The only thing I am using my PIsmo for right now is just Web stuff and Some Graphics for my webpage and Adobe Golive that's it. Will try it with lowered disk cache