[comp.sys.nsc.32k] Minix

jvh@robin.hut.fi (08/15/90)

Especially if you have 8 MB memory, I suggest that you increase the
size of the disk cache in the Minix kernel (NR_BUFS in fs/const.h).  I
changed the size to 2048 and the speed of compilation when making a
Makefile increased drastically. 

With a small cache most of the time in a compilation was spent in
reading the compiler and the like into memory. When the cache is large
enough the compilation times are comparable to a sparc or similar. On
the other hand it makes it more important to say sync before halting.

It probably is a good idea to increase the size of the related hash
table (NR_BUF_HASH (I use 1024)). 256 (NR_BUFS) and 128 seemed
reasonable with 4MBs.  
Some other numbers I increased without problems: 
- number of processes (16 -> 128) NR_PROCS in h/const.h 
- number of superblocks (5 -> 32) NR_SUPERS in fs/const.h

It is funny how most of the numbers seem somewhat underdimensioned
when there are 8 MBs of memory, 1.4GB of disk, and around 10 MIPS in a
Minix system :-), as we had at one time.

	Johannes