Re: stat very inefficient

From: Ulrich Drepper
Date: Thu Jul 29 2004 - 02:48:57 EST


Peter Chubb wrote:

> With hot cache the system time is really small.

But this is not all you'll have to look at.

Single application performs does not really tell the whole story. If
you touch more memory, more cache is used. In SMP machines the cost of
cacheline transfers are added. And in multi-core processors the cores
even share some cache which means every bit used might decrease system
performance ever so slightly.

If the added complexity is manageable the avoided memory operations
should be a win even if you cannot directly measure it.

--
â Ulrich Drepper â Red Hat, Inc. â 444 Castro St â Mountain View, CA â
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