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From: Lyndon Nerenberg <lyndon@orthanc.ca>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Cc: Lyndon Nerenberg <lyndon@orthanc.ca>
Subject: Re: [9fans] PDP11 (Was: Re: what heavy negativity!)
Date: Thu, 11 Oct 2018 10:54:22 -0700	[thread overview]
Message-ID: <7aa20b1cedd55fec@orthanc.ca> (raw)
In-Reply-To: <d73cbcf5-4f11-4d4a-9a03-a31fe3b0931f@email.android.com>

> I have been able to copy 1 GiB/s to userspace from an nvme device. I should
> think a radio should be no problem.

The problem is when you have multiple decoder blocks implemented
as individual processes (i.e. the GNU radio model).  Once you have
everything debugged, you can put it into a single threaded process
and eliminate the copy overhead.  But it's completely impractical
to prototype or debug real applications this way.  And it's the
prototyping case I'm interested in here.

So I'm *curious* to know if page flipping a 'protocol buffer' like
object between processes provides an optimization over copying
through the kernel.  Not so much for the speed aspect, but to free
up CPU cycles that can be devoted to actual SDR work.

Since when did curiosity become a capital crime?   Oh, wait, that
was January 20, 2017.  My bad.

--lyndon



  reply	other threads:[~2018-10-11 17:54 UTC|newest]

Thread overview: 89+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-08  3:38 Lucio De Re
2018-10-08  4:29 ` Digby R.S. Tarvin
2018-10-08  7:20   ` hiro
2018-10-08 12:03     ` Charles Forsyth
2018-10-08 17:20       ` hiro
2018-10-08 21:55         ` Digby R.S. Tarvin
2018-10-08 23:03           ` Dan Cross
2018-10-09  0:14             ` Bakul Shah
2018-10-09  1:34               ` Christopher Nielsen
2018-10-09  3:28               ` Lucio De Re
2018-10-09  8:23                 ` hiro
2018-10-09  9:45                 ` Ethan Gardener
2018-10-09 17:50                   ` Bakul Shah
2018-10-09 18:57                     ` Ori Bernstein
2018-10-10  7:32                 ` Giacomo Tesio
2018-10-09 17:45               ` Lyndon Nerenberg
2018-10-09 18:49                 ` hiro
2018-10-09 19:14                   ` Lyndon Nerenberg
2018-10-09 22:05                     ` erik quanstrom
2018-10-11 17:54                       ` Lyndon Nerenberg [this message]
2018-10-11 18:04                         ` Kurt H Maier
2018-10-11 19:23                         ` hiro
2018-10-11 19:24                           ` hiro
2018-10-11 19:25                             ` hiro
2018-10-11 19:26                         ` Skip Tavakkolian
2018-10-11 19:39                           ` Lyndon Nerenberg
2018-10-11 19:44                             ` Skip Tavakkolian
2018-10-11 19:47                               ` Lyndon Nerenberg
2018-10-11 19:57                                 ` hiro
2018-10-11 20:23                                   ` Lyndon Nerenberg
2018-10-10 10:42                     ` Ethan Gardener
2018-10-09 19:23                   ` Lyndon Nerenberg
2018-10-09 19:34                     ` hiro
2018-10-09 19:36                       ` hiro
2018-10-09 19:40                       ` Lyndon Nerenberg
2018-10-10  0:18                       ` Dan Cross
2018-10-10  5:45                         ` hiro
2018-10-09 22:06                     ` erik quanstrom
2018-10-10  6:24                       ` Bakul Shah
2018-10-10 13:58                         ` erik quanstrom
2018-10-09 22:42                   ` Dan Cross
2018-10-09 19:09                 ` Bakul Shah
2018-10-09 19:30                   ` Lyndon Nerenberg
2018-10-09  3:08             ` Digby R.S. Tarvin
2018-10-09  3:16               ` [9fans] PDP11 David Arnold
2018-10-09  4:52                 ` Digby R.S. Tarvin
2018-10-09 11:58               ` [9fans] PDP11 (Was: Re: what heavy negativity!) Ethan Gardener
2018-10-09 13:59                 ` erik quanstrom
2018-10-09 22:22                 ` Digby R.S. Tarvin
2018-10-10 10:38                   ` Ethan Gardener
2018-10-10 23:15                     ` Digby R.S. Tarvin
2018-10-11 18:10                       ` Lyndon Nerenberg
2018-10-11 20:55                         ` Digby R.S. Tarvin
2018-10-11 21:03                           ` Lyndon Nerenberg
2018-10-09 14:02               ` erik quanstrom
2018-10-08  8:12   ` Nils M Holm
2018-10-08  9:12     ` Digby R.S. Tarvin
2018-10-08  8:09 ` Nils M Holm
2018-10-09 19:47 cinap_lenrek
2018-10-09 22:01 ` erik quanstrom
2018-10-09 23:43 ` Lyndon Nerenberg
2018-10-10  5:52   ` hiro
2018-10-10  8:13     ` Digby R.S. Tarvin
2018-10-10  9:14       ` hiro
2018-10-10 13:59         ` Steve Simon
2018-10-10 21:32         ` Digby R.S. Tarvin
2018-10-11 17:43     ` Lyndon Nerenberg
2018-10-11 19:11       ` hiro
2018-10-11 19:27         ` Lyndon Nerenberg
2018-10-11 19:56           ` hiro
2018-10-10  5:57   ` hiro
2018-10-09 19:49 cinap_lenrek
2018-10-09 19:56 ` hiro
2018-10-10  0:15 cinap_lenrek
2018-10-10  0:22 ` Lyndon Nerenberg
2018-10-10 16:14 cinap_lenrek
2018-10-10 17:34 cinap_lenrek
2018-10-10 21:54 ` Steven Stallion
2018-10-10 22:29   ` Kurt H Maier
2018-10-10 22:55     ` Steven Stallion
2018-10-11 11:19       ` Aram Hăvărneanu
2018-10-11  0:26   ` Skip Tavakkolian
2018-10-11  1:03     ` Steven Stallion
2018-10-14  9:46   ` Ole-Hjalmar Kristensen
2018-10-14 10:37     ` hiro
2018-10-14 17:34       ` Ole-Hjalmar Kristensen
2018-10-14 19:17         ` hiro
2018-10-15  9:29         ` Giacomo Tesio
2018-10-10 22:19 cinap_lenrek

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