JNI-performance - Is it really that fast?

Clemens Eisserer linuxhippy at gmail.com
Wed Mar 26 23:46:23 UTC 2008

> No problem at all (:>).
>  Is your pentium4 a uniprocessor?  On uniprocessors HotSpot elides the
>  lock: prefix when emitting the Intel cmpxchg (CAS) instruction.  The
>  lock prefix forces the cmpxchg to be serializing and greatly increases
>  the latency but that's unnecessary on uniprocessors as they're always
>  self-consistent.  (Even multiple threads on a uniprocessor are always
>  self-consistent with respect to the memory model).
Exactly, its a uniprocessor.

Thanks a lot for clarification and for your patience, suggestions and
comments :)

lg Clemens

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