[GRASSLIST:3178] Re: advice on building a workstation PC for Grass

[James Plante]

On Apr 14, 2004, at 10:45 PM, Glynn Clements wrote:

>
> Philipp Molzer wrote:
>
>> I'd appreciate any advice on building a new PC, with running Grass in
>> mind.  I am currently using
>> AMD Duron Processor
>> cpu MHz         : 1294.521
>> RAM : 750 MB
>> Linux 2.4.20-28.8
>> The ram seems to be fine, but the CPU frequently max's out on things
>> such as v.in.shape, r.patch, etc.
>> I'd like to stay under $600 for motherboard, CPU, RAM, harddrive, and
>> case.  I know I am being quite vague about what sort of data I'm 
>> working
>> with, but I'm sure that people must have opinions about what a 
>> dedicated
>> Grass workstation would have in it.
>
> It depends on the nature of the workload. If you are doing simple,
> serial-access computations on large amounts of data, disk bandwidth
> will be the limiting factor. For computations which involve
> random-access, RAM is significant. For intensive computations on small
> amounts of data, the CPU speed will be the limiting factor. If you
> read certain maps repeatedly, having sufficient RAM to cache them will
> improve the situation.
>
> Except in extreme cases where the answer would be obvious, it's almost
> impossible to predict which will be the limiting factor. You just have
> to observe the behaviour (CPU/memory/disk usage) of an existing
> system.
>
The General Rules of Computing Machinery seem to apply:
1) Every program expands to fill all available memory.
1a) Every database expands to fill all available disks.
2) With respect to RAM, disk space, and CPU speed: some is good, more 
is better, and too much is just enough!
3) Whatever you build will be obsolete in 18 months.

RAID, 64-bit CPU, 2GB RAM, and two or three big honkin' monitors.

Jim Plante
<jimplante at charter.net>