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From: Steven Stallion <sstallion@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] zero copy & 9p (was Re: PDP11 (Was: Re: what heavy negativity!)
Date: Wed, 10 Oct 2018 22:20:05 -0500	[thread overview]
Message-ID: <CAGGHmKEsHLE5-UiHnyKFR--qXOCJs-pPmABaVj1hTMdiuV3t_A@mail.gmail.com> (raw)
In-Reply-To: <20181011023054.2E6AC156E40C@mail.bitblocks.com>

On Wed, Oct 10, 2018 at 9:32 PM Bakul Shah <bakul@bitblocks.com> wrote:
> Steve wrote "1:1 mapping of the virtual kernel address space such
> that something like zero-copy could be possible"
>
> Not sure what he meant. For zero copy you need to *directly*
> write to the memory allocated to a process. 1:1 mapping is
> really not needed.

Ugh. I could have worded that better. That was a (very) clumsy attempt
at stating that the kernel would have to support remapping the user
buffer to virtual kernel space. Fortunately Plan 9 doesn't page out
kernel memory, so pinning wouldn't be required.

Cheers,
Steve



  reply	other threads:[~2018-10-11  3:20 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-10 23:58 cinap_lenrek
2018-10-11  0:56 ` Dan Cross
2018-10-11  2:26   ` Steven Stallion
2018-10-11  2:30   ` Bakul Shah
2018-10-11  3:20     ` Steven Stallion [this message]
2018-10-11 14:21       ` [9fans] ..... UNSUBSCRIBE_HELP NEEDED DHAN HURLEY
  -- strict thread matches above, loose matches on Subject: below --
2018-10-10 17:34 [9fans] PDP11 (Was: Re: what heavy negativity!) cinap_lenrek
2018-10-10 21:54 ` Steven Stallion
2018-10-10 22:26   ` [9fans] zero copy & 9p (was " Bakul Shah
2018-10-10 22:52     ` Steven Stallion
2018-10-11 20:43     ` Lyndon Nerenberg
2018-10-11 22:28       ` hiro
2018-10-12  6:04       ` Ori Bernstein
2018-10-13 18:01         ` Charles Forsyth
2018-10-13 21:11           ` hiro
2018-10-14  5:25             ` FJ Ballesteros
2018-10-14  7:34               ` hiro
2018-10-14  7:38                 ` Francisco J Ballesteros
2018-10-14  8:00                   ` hiro
2018-10-15 16:48                     ` Charles Forsyth
2018-10-15 17:01                       ` hiro
2018-10-15 17:29                       ` hiro
2018-10-15 23:06                         ` Charles Forsyth
2018-10-16  0:09                       ` erik quanstrom
2018-10-17 18:14                       ` Charles Forsyth

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