🚀 go-pugleaf

In comp.os.linux.hardware Totally Lost <idletime@my-dejanews.com> wrote:

: Celron's with their 128K L2 cache can easily produce worse performance
: under modest to heavy load than a single processor in an SMP system.

Don't forget: PPros had only 256K L2 and everbody was just satisfied :-)



: In many server systems, even dual PII's with 512K L2 caches fail to
: scale or produce negative results under modest to heavy work loads.
: In some applications, even Xenon's large caches fail to scale or
: produce negative results in comparision to uniprocessors of the same
: architecture. Simply put, it's not uncommon to find applications where
: two processors trashing the caches with SMP interrupts or shared memory
: produce much worse performance than the same system with only a single
: processor enabled.

Of course, you can _always_ find an appication that doesn't fit
into an L2-Cache (and that will ever be).



: I would expect that for many users, dual Celeron's may have a negative
: performance impact much of the time.

You _expect_? I have _experiences_: up to 90% speedup at code-compilation
(yes, with Dual-Celeron)



: To observe that Dual Celron's produce an observed improvement under
: certain lightly loading applications may be true. To assert that
: they scale under modest to heavy work loads is probably a huge mistake.

It's always a question of code locality: a Dual Celeron may be
faster than a Dual PII at the same clockrate since the Celeron's
L2 is twice as fast.



: To expect that they will scale well under Linux with heavy loads is
: almost certainly folly.

hmm ... i tried a load of ten ... the machine didn't felt slow
at all. :-)

A friend of mine did some benchmarks with dual PII/350 and
Dual Celeron 333: the Celerons were only 10-20% slower
at many Applications (compilation, gaming, rendering etc.)
but they are a third the price ...


You should forget you theoretical considerations (which are close
to FUD) and do some practical works!
PII and Celeron are realy very close in performance but very
different in price (that one who buys a PII instead of a Celeron
is realy silly or forced to).

In dual-mode the Celerons are only a little bit slower than Dual PII, but
1) the Price is much lower, so the performance/price ratio is much better
2) if i realy had a mission critcal Server under heavy load, then i
   would buy a _real_ Computer (i am not talking of Xeons)

Especial for Home-Multimedia on Linux, the (Dual)Celeron are the
better choice (Oh i have forgotten to mention PIII: it even
speeds up the internet, according to intel's advertising in germany)

Ok, the Celerons would scale lousy on a Quad- or Octa-SMP-System, but
that is theorie, because Celerons and PII can only do dual-operation


So, now it's your turn!


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