Yes, when the data set can't be kept in memory, and has to hit the hard drive, it slows things down a lot. That's why for applications servers or workstations, sometimes the amount of memory is a bigger factor than the speed of the CPU, or memory, or hard drive. For file servers, of course you can't keep all the data in memory, your storing things and have no idea when someone will need a particular piece of data. You can speed things up a bit with RAID configurations, and for repeatedly accessed data caching can help, but the HDs can certainly be a major bottleneck.
On individual computers, you might be able to load all the programs in to memory, so you don't have to hit the HD all the time. But some programs are real memory hogs, and if your manipulating lots of data, calling up files and saving them all the time obviously you have to hit the HD, even if the program doesn't have that much memory overhead.
Vista in particular has had a problem with certain types of file copies. That's generally improved in SP1, but I understand that sometimes SP1 doesn't help.
The programs that slowed SP1 down the most in the article I posted, where mainly security programs that scanned files when you accessed them, so you not only have the time to access the file, you have the additional overhead of the scan. |
