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From: Keith Wright <kwright@keithdiane.us>
To: Zelphir Kaltstahl <zelphirkaltstahl@posteo.de>
Cc: damien.mattei@gmail.com, guile-user@gnu.org
Subject: Re: map-par slower than map
Date: Sun, 23 Oct 2022 23:56:58 -0400	[thread overview]
Message-ID: <878rl5kh6d.fsf@fcs22.keithdiane.us> (raw)
In-Reply-To: <87860c1f-e590-8e16-e031-dedc99cd3864@posteo.de> (message from Zelphir Kaltstahl on Sun, 23 Oct 2022 23:18:58 +0000)

Zelphir Kaltstahl <zelphirkaltstahl@posteo.de> writes:

> Of course,if you have global state and do not have a synchronization
> construct for accessing the hash table, I would expect things to
> go wrong at some point, with non-reproducible results.

Indeed.

> I do not think that futures are to blame here,
> or parallel map in that case.

Are futures to blame?  Do you blame the plus sign for
this wrong equation:  4+5=20?
My teachers blamed me for that sort of thing.

> With a synchronization construct, some kind of mutex,
> your bottle neck might just become that mutex.

But why make it parallel at all?  Unless you have some serious
parallel hardware you will just be wasting time in the scheduler
when you could be computing the answer.

In other news --- there are many kinds of people on this mailing
list.  I wonder what percentage are the kind that needs page-long
disjunctive normal form expressions in their mail boxes?

Not me.

   -- Keith

PS: For page-long boolean expression, they are nice.  But why?



  reply	other threads:[~2022-10-24  3:56 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-12 17:19 map-par slower than map Damien Mattei
2022-10-12 18:45 ` Maxime Devos
2022-10-12 20:20   ` Damien Mattei
2022-10-12 20:27     ` Damien Mattei
2022-10-12 21:29       ` Zelphir Kaltstahl
2022-10-14  8:21         ` Damien Mattei
2022-10-14  8:38           ` Zelphir Kaltstahl
2022-10-17 13:17             ` Damien Mattei
2022-10-22 16:01               ` Damien Mattei
2022-10-23  1:06                 ` Damien Mattei
2022-10-23 23:18                   ` Zelphir Kaltstahl
2022-10-24  3:56                     ` Keith Wright [this message]
2022-10-24  7:03                       ` Zelphir Kaltstahl
2022-10-24  4:39                     ` Damien Mattei
2022-10-25  9:07         ` Mikael Djurfeldt
2022-10-25  9:11           ` Mikael Djurfeldt
2022-10-25 14:09             ` Damien Mattei
2022-11-10 10:32         ` Damien Mattei
2022-11-10 10:41           ` Damien Mattei
2022-11-10 10:52             ` Zelphir Kaltstahl
2022-11-10 13:36               ` Damien Mattei
2022-11-10 17:07           ` Olivier Dion via General Guile related discussions
2022-11-11 10:26             ` Damien Mattei
2022-11-11 12:25               ` Zelphir Kaltstahl
2022-11-11 13:36                 ` Damien Mattei
2022-11-11 13:37                   ` Damien Mattei
2022-11-13  8:23                     ` Damien Mattei
2022-10-12 21:44     ` Maxime Devos
2022-10-12 21:55 ` Olivier Dion via Developers list for Guile, the GNU extensibility library
2022-10-13  7:40   ` Damien Mattei
2022-10-13  8:20     ` Damien Mattei
2022-10-13  9:10     ` Olivier Dion via Developers list for Guile, the GNU extensibility library
2022-10-13 10:44   ` Damien Mattei
2022-10-13 11:00     ` Olivier Dion via Developers list for Guile, the GNU extensibility library
     [not found]       ` <CADEOadfovi8s3OxRcssWOuOW8jjHoL9Z7pD_5FstSm=ZkBHP8g@mail.gmail.com>
2022-10-13 11:57         ` Fwd: " Damien Mattei
2022-10-13 12:36           ` Damien Mattei
2022-10-13 12:41             ` Olivier Dion via Developers list for Guile, the GNU extensibility library
2022-10-13 13:43               ` Damien Mattei
2022-10-13 14:06                 ` Olivier Dion via Developers list for Guile, the GNU extensibility library
2022-10-13 14:10                   ` Damien Mattei
2022-10-13 14:21                     ` Damien Mattei

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