Linked by Thom Holwerda on Mon 11th May 2009 20:43 UTC
Windows SuperFetch is a technology in Windows Vista and onwards that is often misunderstood. I decided to delve into this technology to see what it is all about, and to dispel some of the myths surrounding this feature.
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WereCatf
Member since:
2006-02-15

The only 2 ways in which superfetch could technically be a disadvantage are these:
- if the IO priority system is screwed, the reading superfech does COULD interfere with other activity. Depends on the quality of the kernel's management of priorities. No idea if this is an issue at all, I doubt it, but it is possible.
- superfech uses resources while your PC wouldn't have been doing anything if it weren't running. Bad for powerusage = environment and probably slightly bad for the lifespan of your hardware.


I can think of atleast one case where SuperFetch is a disadvantage: if you are playing a game the game will most likely read its files in more-or-less sequential order, and disk cache will load the parts of the files it assumes will be needed next. But if SuperFetch is caching something in the background while you're playing then it'll invalidate the disk cache causing slightly longer loading times.

Now, I'm not saying that's a big issue though. It's most likely negligible enough for most people not to care. I just mentioned it for the sake of argument.

Reply Parent Score: 3

superstoned Member since:
2005-07-07

Well, yes, it is a valid issue. Caching algorithms would probably be a bit bad to not take such a situation into account, but when low on memory it might happen.

Furthermore, from the threads below I understand the IO priority system in windows isn't at the level of quality it would need to be to prevent prefetch from having an adverse effect on the performance of the system. In other words, the first disadvantage I considered so unlikely seems to be hurting users...

Reply Parent Score: 2

lemur2 Member since:
2007-02-17

Furthermore, from the threads below I understand the IO priority system in windows isn't at the level of quality it would need to be to prevent prefetch from having an adverse effect on the performance of the system.


Indeed. One could only hope for an actual benefit from preloaders if the preloader uses ONLY system resources that are idle at the time. There must be spare (unused) RAM and the CPU and disk must be idle when the pre-loader is operating, otherwise the preloader will reduce speed and responsiveness of the overall system where it supposed to be assisting.

Edited 2009-05-12 11:12 UTC

Reply Parent Score: 2