DragonFly users List (threaded) for 2005-03
Nomenclature Change Request
'After the holidays'....
Request DragonFlyBSD project consider exchanging
at least 'external' use of the term 'SMP' for one more
appropriate and, one trusts - *advantageous* in future.
'HMP' (Hybrid Multi Processing)
'DMP' (Dynamic, or Distributed Multi Processing)
'MMP' (Message-based Multi Processing)
or? (other candidates, please...)
- Implementation of DragonFly (and earlier 'SMP' OS),
is already rarely, in fact, 'Symmetrical', and can be expected
to become progressively less so.
Intel HAL 1.X spec leaves interrupt handling to one
CPU only, NUMA architecture allows different RAM
complement and even speed, some MB route all
RAM access via one CPU, while others use crossbar
switch matrices to allow one, many, none, etc.
IBM Warp Server 'SMP' achieved near-unity-gain with
big-iron-derived 'hybrid', not 'symmetrical'
MP - but we do NOT want to go either their 'spinlock'
route or their hand-optimized-for X86 code route.
Costly, limited, expensive to code to. Inflexible.
DragonFly's flexible message-passing philosophy,
OTOH, which may at times be either/both asynchronous
or synchronous, provides a more flexible and general
purpose mechanism to enable further de-coupling of
the OS and applications from the hardware layer in
general, or a specific CPU / point in time, in particular.
This appears to be both a practical necessity to be better
able to cope with newer hardware as it comes along,
and a powerful advantage w/r implementation, scaling,
an porting that other methods.
Differentiating DragonFlyBSD by stressing this
point should certainly make clear that it is not
'just another *BSD', nor less capable than Linux
of the month.
One hope and trusts, of course, that it will come
to pass... and that DragonFlyBSD will work as well
in practice as in concept.