4.2 scheduler

[Stanley Friesen]

In article <3058 at sun.uucp> guy at sun.uucp (Guy Harris) writes:
>>	(me)
>> 	Well, I  consider 30% to be reasonable, but I find 50% and up
>> to be excessive, after all the machine is really there to execute
>> *user* code, not the kernal!
>
>Well, let me ask a couple of questions:
>
>	1) how much work would that user code be able to do if
>	   the kernel weren't doing opens, reads, writes, etc. for you?
>
	Except that the older versions were doing all that at an
overhead of only 30-40%, why should I "pay" more for the same
functions? In fact 90% of our work here is compiling and editing, with
a little troff thrown in. As far as I know these utilities are little
changed between 4.1 and 4.2. Certainly they expect much the same
services out of the kernel. The net result is that for the same user
load, with the same job mix, we are getting much slower response
time.

>	2) how much of the user code in question is actually
>	   doing "support work" for the part of the user code
>	   that's doing the real work?
>
	I don't really know, but I suspect that specialized,
tailor-made support code is going to be more efficient than the
generalized support available from the kernel.
-- 

				Sarima (Stanley Friesen)

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