Enhancing Alpha/Linux Experiences

[Jon maddog Hall]

mshlitz at yahoo.com said:
> I'd be open to suggestions as to what I can do to "enhance" my Alpha
> experience.

Since we now have an opportunity to create a technical discussion......

One of the things that made the Alpha/Linux combination so fast was that the
Alpha systems typically have a very large cache at every level of memory.
While lots of systems are very responsive to keeping things in cache, the Alpha
is even more responsive.  Alpha Linux was a screamer because the kernel was
so small at the time that you could keep the entire kernel, a lot of the
command interpreter and even a portion of the application in the CPU's
cache.

A friend of mine wrote a program that purposely did the same thing with the
same algorithm, but one time was trying to trash cache, and the next time
tried to keep cache warm.  There was a 40 TIMES performance improvement of the
same program.  With Intel there was a 10 times performance improvement for the
same programs/test, because the Intel chip was not as sensitive to cache
issues.

Moral of the story is to configure your Alpha/Linux kernel to use the smallest
configuration possible, to get as much other programs and data into cache as
possibloe.

md
-- 
Jon "maddog" Hall
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