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Re: Any exp with NTw/2 to 4 hamster wheels?

From: Charlie Mengler <>
Date: Wed, 06 Dec 2000 13:34:07 -0800
Message-Id: <>

If the two existing CPUs are under utilized, add two more CPUs will have limited or marginal benefit; if any measurable affect.

As a general rule only when a resource (memory, CPU cycles, disk I/O throughput, network bandwidth) is be run at 100% of capacity will much be gained by adding more of that resource.

For example assume that you have 1" wide water pipe that can carry 10 liters per second, BUT it is only carrying 5 liters per second. Changing the pipe to be a 2" pipe will NOT change the 5 liter per second flow! The water in this case is flowing at 5L/Sec because of some other bottleneck that is restircting the flow. To make the water flow faster than 5L/sec. you need to identify & eliminate the bottleneck.

The term "bottleneck" is used because it is the neck of the bottle that limits how quickly the bottle can be either filled or emptied. Changing the size of the bottle will not affect the rate at which the water can pass through the neck of the bottle.

HTH & YMMV! "Eric D. Pierce" wrote:
> i think a better question is: "why *wouldn't* you see a performance
> increase?". you put more hamsters on more wheels, more things will
> spin around faster w/ greater torque, no?
> ep
> On 6 Dec 2000, at 6:20, The Oracle DBA wrote:
> > A client seems to be seeing now perf improv with adding 2 more
> > procs to a 2 proc NT box. Anyone see a similar result? This is 805
Received on Wed Dec 06 2000 - 15:34:07 CST

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