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From: Paul Winalski <paul.winalski@gmail.com>
To: TUHS main list <tuhs@minnie.tuhs.org>
Subject: Re: [TUHS] PDP-11 legacy, C, and modern architectures
Date: Wed, 27 Jun 2018 11:30:47 -0400	[thread overview]
Message-ID: <CABH=_VScs_KqX0v0-Cc6LaOjwnLvQk0B+wYzjWngYuu+YYsoQA@mail.gmail.com> (raw)
In-Reply-To: <CAC20D2P6LcfP9HD6VrmGH35NkUL873h51ZJLs5HABB1B2ygADg@mail.gmail.com>

What Clem said.  Chisnall is right about C having been designed for a
sequential-programming world.  That's why Fortran (with array and
other parallel/vector operations built in) rules in the HPTC parallel
programming space.  But I don't buy most of his arguments.  Making
parallel programming easy and natural has been an unsolved problem
during my entire 30+ year career in designing software development
tools.  It's still an unsolved problem.  Modern compiler technology
helps to find the hidden parallelism in algorithms expressed
sequentially, but I think the fundamental problem is that most human
beings have great difficulty conceptualizing parallel algorithms.
It's also always been true that to get maximum performance you have to
somehow get close to the specific hardware you're using--either by
explicitly programming for it, or by having a compiler do that for
you.

Note also that there have been extensions to C/C++ to support
parallelism.  Cilk, for example.

-Paul W.

  parent reply	other threads:[~2018-06-27 15:31 UTC|newest]

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-26 17:54 Nelson H. F. Beebe
2018-06-26 18:03 ` Cornelius Keck
2018-06-26 21:21   ` Nelson H. F. Beebe
2018-06-26 21:56   ` Kurt H Maier
2018-06-26 18:52 ` Ronald Natalie
2018-06-26 19:01 ` Ronald Natalie
2018-06-26 21:16   ` Arthur Krewat
2018-06-26 21:50     ` Larry McVoy
2018-06-26 21:54       ` Ronald Natalie
2018-06-26 21:59         ` Larry McVoy
2018-06-26 22:20           ` Bakul Shah
2018-06-26 22:33             ` Arthur Krewat
2018-06-26 23:53               ` Bakul Shah
2018-06-27  8:30             ` Tim Bradshaw
2018-06-26 22:33           ` Andy Kosela
2018-06-27  0:11             ` Bakul Shah
2018-06-27  6:10               ` arnold
2018-06-27  2:18           ` [TUHS] PDP-11 legacy, C, and modern architectTures Theodore Y. Ts'o
2018-06-27  2:22             ` Theodore Y. Ts'o
2018-06-28 14:36             ` Steffen Nurpmeso
2018-06-27 11:26         ` [TUHS] PDP-11 legacy, C, and modern architectures Tony Finch
2018-06-27 14:33           ` Clem Cole
2018-06-27 14:38             ` Clem Cole
2018-06-27 15:30             ` Paul Winalski [this message]
2018-06-27 16:55               ` Tim Bradshaw
2018-06-27  6:27     ` arnold
2018-06-27 16:00 ` Steve Johnson
2018-06-28  4:12   ` Bakul Shah
2018-06-28 14:15     ` Theodore Y. Ts'o
2018-06-28 14:40       ` Larry McVoy
2018-06-28 14:55         ` Perry E. Metzger
2018-06-28 14:58           ` Larry McVoy
2018-06-28 15:39             ` Tim Bradshaw
2018-06-28 16:02               ` Larry McVoy
2018-06-28 16:41                 ` Tim Bradshaw
2018-06-28 16:59                   ` Paul Winalski
2018-06-28 17:09                   ` Larry McVoy
2018-06-29 15:32                     ` tfb
2018-06-29 16:09                       ` Perry E. Metzger
2018-06-29 17:51                       ` Larry McVoy
2018-06-29 18:27                         ` Tim Bradshaw
2018-06-29 19:02                         ` Perry E. Metzger
2018-06-28 20:37                 ` Perry E. Metzger
2018-06-28 15:37         ` Clem Cole
2018-06-28 20:37           ` Lawrence Stewart
2018-06-28 14:43       ` Perry E. Metzger
2018-06-28 14:56         ` Larry McVoy
2018-06-28 15:07           ` Warner Losh
2018-06-28 19:42           ` Perry E. Metzger
2018-06-28 19:55             ` Paul Winalski
2018-06-28 20:42             ` Warner Losh
2018-06-28 21:03               ` Perry E. Metzger
2018-06-28 22:29                 ` Theodore Y. Ts'o
2018-06-29  0:18                   ` Larry McVoy
2018-06-29 15:41                     ` Perry E. Metzger
2018-06-29 18:01                       ` Larry McVoy
2018-06-29 19:07                         ` Perry E. Metzger
2018-06-29  5:58                   ` Michael Kjörling
2018-06-28 20:52             ` Lawrence Stewart
2018-06-28 21:07               ` Perry E. Metzger
2018-06-28 16:45       ` Paul Winalski
2018-06-28 20:47         ` Perry E. Metzger
2018-06-29 15:43         ` emanuel stiebler
2018-06-29  2:02       ` Bakul Shah
2018-06-29 12:58         ` Theodore Y. Ts'o
2018-06-29 18:41           ` Perry E. Metzger
2018-06-29  1:02 Noel Chiappa
2018-06-29  1:06 Noel Chiappa

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