Threads simulated in software are a kludge to better utilize current
processor and operating system architectures. In time machines where
the parallelism is handled in hardware will be more widely available and
the threading will be transparent and highly efficient.
Joe Wilson wrote:
Threads are very much in the C tradition - minimalistic.
If you code in C you must know what you're doing anyway.
C is by no means a high level or safe language.
But until an automatically parallelizing safe language with
good performance becomes popular - this is what we got.
You just have to rely on simple conventions to minimize the
risks.
--- Michael Scharf <[EMAIL PROTECTED]> wrote:
Why Threads Are A Bad Idea:
http://www.eecs.berkeley.edu/Pubs/TechRpts/2006/EECS-2006-1.pdf
From the article:
"Threads are a seemingly straightforward adaptation of the
dominant sequential model of computation to concurrent
systems. Languages require little or no syntactic changes to
support threads, and operating systems and architectures
have evolved to efficiently support them. Many technologists
are pushing for increased use of multithreading in software
in order to take advantage of the predicted increases in
parallelism in computer architectures. In this paper, I
argue that this is not a good idea. Although threads seem to
be a small step from sequential computation, in fact, they
represent a huge step. They discard the most essential and
appealing properties of sequential computation:
understandability, predictability, and determinism. Threads,
as a model of computation, are wildly nondeterministic, and
the job of the programmer becomes one of pruning that
nondeterminism. Although many research techniques improve
the model by offering more effective pruning, I argue that
this is approaching the problem backwards. Rather than
pruning nondeterminism, we should build from essentially
deterministic, composable components. Nondeterminism should
be explicitly and judiciously introduced where needed,
rather than removed where not needed. The consequences of
this principle are profound. I argue for the development of
concurrent coordination languages based on sound, composable
formalisms. I believe that such languages will yield much
more reliable, and more concurrent programs."
____________________________________________________________________________________
Be a better pen pal.
Text or chat with friends inside Yahoo! Mail. See how. http://overview.mail.yahoo.com/
-----------------------------------------------------------------------------
To unsubscribe, send email to [EMAIL PROTECTED]
-----------------------------------------------------------------------------
-----------------------------------------------------------------------------
To unsubscribe, send email to [EMAIL PROTECTED]
-----------------------------------------------------------------------------
