Re: memset (was: Redundant memset in AIO read_events)

Arjan van de Ven
2003-07-10T10:04:48Z

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On Thu, 2003-07-10 at 12:04, Etienne Lorrain wrote:
> Note that using memset() is better reserved to initialise variable-size
> structures or buffers. Even if memset() is extremely optimised,
> it is still not as fast as not doing anything.

this is not always true....
memset can be used as an optimized cache-warmup, which can avoid the
write-allocate behavior of normal writes, which means that if you memset
a structure first and then fill it, it can be halve the memory bandwidth
and thus half as fast. This assumes an optimized memset which we
*currently* don't have I think... but well, we can fix that ;)

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