From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 References: <7aa20c07322147e6@orthanc.ca> <20181011230430.8ec148a3cb2a4d95180a4ad2@eigenstate.org> In-Reply-To: <20181011230430.8ec148a3cb2a4d95180a4ad2@eigenstate.org> From: Charles Forsyth Date: Sat, 13 Oct 2018 19:01:00 +0100 Message-ID: To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: multipart/alternative; boundary="0000000000005e039105781ffd7f" Cc: Lyndon Nerenberg Subject: Re: [9fans] zero copy & 9p (was Re: PDP11 (Was: Re: what heavy negativity!) Topicbox-Message-UUID: ed51fd0e-ead9-11e9-9d60-3106f5b1d025 --0000000000005e039105781ffd7f Content-Type: text/plain; charset="UTF-8" I did several versions of one part of zero copy, inspired by several things in x-kernel, replacing Blocks by another structure throughout the network stacks and kernel, then made messages visible to user level. Nemo did another part, on his way to Clive On Fri, 12 Oct 2018, 07:05 Ori Bernstein, wrote: > On Thu, 11 Oct 2018 13:43:00 -0700, Lyndon Nerenberg > wrote: > > > Another case to ponder ... We're handling the incoming I/Q data > > stream, but need to fan that out to many downstream consumers. If > > we already read the data into a page, then flip it to the first > > consumer, is there a benefit to adding a reference counter to that > > read-only page and leaving the page live until the counter expires? > > > > Hiro clamours for benchmarks. I agree. Some basic searches I've > > done don't show anyone trying this out with P9 (and publishing > > their results). Anybody have hints/references to prior work? > > > > --lyndon > > > > I don't believe anyone has done the work yet. I'd be interested > to see what you come up with. > > > -- > Ori Bernstein > > --0000000000005e039105781ffd7f Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
I did several versions of one part of zero copy, inspired= by several things in x-kernel, replacing Blocks by another structure throu= ghout the network stacks and kernel, then made messages visible to user lev= el. Nemo did another part, on his way to Clive=C2=A0

On Fri, 12 Oct 2018, 07:05 Ori Bernstein, &l= t;ori@eigenstate.org> wrote:
On Thu, 11 Oct 2018 13:43:00 -0700, = Lyndon Nerenberg <lyndon@orthanc.ca> wrote:

> Another case to ponder ...=C2=A0 =C2=A0We're handling the incoming= I/Q data
> stream, but need to fan that out to many downstream consumers.=C2=A0 I= f
> we already read the data into a page, then flip it to the first
> consumer, is there a benefit to adding a reference counter to that
> read-only page and leaving the page live until the counter expires? >
> Hiro clamours for benchmarks.=C2=A0 I agree.=C2=A0 Some basic searches= I've
> done don't show anyone trying this out with P9 (and publishing
> their results).=C2=A0 Anybody have hints/references to prior work?
>
> --lyndon
>

I don't believe anyone has done the work yet. I'd be interested
to see what you come up with.


--
=C2=A0 =C2=A0 Ori Bernstein

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