** notes that I kept
Vcache is essentially smartdrv (Disk caching) for Windows, except that it's 32 bit, built into the Windows 9X/NT OS, and shares the same memory pool as running applications. The reason you add the vcache lines is that by default, Microsoft rather generously grants memory to vcache, which is an incredible miser about returning it to the free memory pool. So what happens and why it helps is that by default eventually all or nearly all free physical memory in your machine not already allocated to running applications will be allocated to vcache, and once that happens any application requesting memory is allocated from the virtual memory swap file.
Vcache is the disk cache. It's a region of RAM that the windows
uses to read pieces of recently used data on the disk. When
windows needs something off the disk, it will look in the cache
first for it. If it's not there, then it will go to the disk for
it. Likewise, when ever a disk write operation occurs, it is also
written to the cache. By keeping recently used data in the cache,
which is also the data that windows will most likely need in the
immediate future, disk access is kept to a minimum and made more efficient. RAM access is orders of magnitude faster than disk
access. The entries in system.ini what we typically do are to
size the cache region of RAM manually, as windows default values
are thought to be too small. If you make the cache too big however, it can decrease performance 'cause you're tying up RAM that windows could use for other things.
For up to 128Mb use the max setting formula of (RAM in MB)(0.25)
x 1025
For 128 to 256Mb I generally use the same formula except I multiply it all by 0.75
For 256 to 384Mb I multiply it all by 0.50
For over 384, I keep it at 384 x .25 x 1024 x .5 = 49152...
(which is getting pretty stinkin huge, no sense going any
larger no matter how much ram you have)
For the Min amount, just halve whatever the Max amount is.
Chunksize is always 512. (In fact, that's the default)
128 megs x 0.25 x 1024 = 32768 max
128 megs x 0.25 x 1024 x 0.75 = 24576 max
256 megs x 0.25 x 1024 x 0.75 = 49152 max
256 megs x 0.25 x 1024 x 0.50 = 32768 max
384 megs x 0.25 x 1024 x 0.50 = 49152 max
512 megs x 0.25 x 1024 x 0.50 = 65536 max
(The "MIN" are half of the "MAX )
>>> OR <<<<
MinFileCache=32768
MaxFileCache=65536
ChunkSize=512PS: And add this to your 386Enh section
[386Enh]
ConservativeSwapfileUsage=1 Your choice really what number you use... the differences it will
make are trivial after you reach a certain level of ram,
that's why after you hit 384 you level off on the cache size.
49152 is a pretty big cache allocation...
The best writeup of vcache optimization and why it is (and isn't in some cases) necessary is here:
http://www.rojakpot.com/Speed_Demonz.htm Give it a read.. this guy's done his homework. While you're at it, read the chunksize and swapfile optimizations too. Pay particular attention to the section on sizing the swapfile. Note that the more ram you have, the SMALLER it should be.... not the opposite.
When you're done that and really want to be confused, readup about the Namecache and Pathcache settings in your registry under the heading "MAX CACHE SPEED" here:
http://users.aol.com/axcel216/newtip16.htm 
