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Re: Are We Back to the "Wars" Now ?

From vallor <vallor@cultnix.org>
Newsgroups comp.os.linux.misc
Subject Re: Are We Back to the "Wars" Now ?
Date 2024-11-23 03:25 +0000
Message-ID <lqd08jFisv3U1@mid.individual.net> (permalink)
References (7 earlier) <wwvcyio8m9p.fsf@LkoBDZeT.terraraq.uk> <vhorrb$t48o$1@dont-email.me> <vhosra$1171f$1@dont-email.me> <lqalg1F7fi9U2@mid.individual.net> <vhql0r$1a0ch$2@dont-email.me>

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On Fri, 22 Nov 2024 19:11:23 -0000 (UTC), Rich <rich@example.invalid>
wrote in <vhql0r$1a0ch$2@dont-email.me>:

> vallor <vallor@cultnix.org> wrote:
>> On Fri, 22 Nov 2024 03:12:43 -0000 (UTC), Lawrence D'Oliveiro
>> <ldo@nz.invalid> wrote in <vhosra$1171f$1@dont-email.me>:
>> 
>>> On Thu, 21 Nov 2024 21:55:37 -0500, Phillip Frabott wrote:
>>> 
>>>> We had to drop named pipes solely because of the performance hit
>>>> because it is writing to a file system so it's being controlled by
>>>> the file system, even if that file system is in memory.
>>> 
>>> That doesn’t make any sense, if we were talking about Linux. Is this
>>> on Windows, by any chance?
>> 
>> Doesn't the named pipe connection work through the filesystem code?
>> That could add overhead.
> 
> Only to the extent that a filesystem lookup has to occur to lookup the
> name in order to open() the name.
> 
> Once you have a file descriptor back from the open() call, there is no
> difference at all kernel wise betwenn the two, they are one and the same
> block of kernel code.

I stand corrected about that.

> 
>> Can't use named pipes on just any filesystem -- won't work on NFS for
>> example, unless I'm mistaken.
> 
> Correct, you need a filesystem that supports storing a 'name' that that
> is a reference to a pipe, so windows filesystems are out.
> 
> Named pipes appear as 'pipe' nodes across NFS (just tested this to be
> certian).  And, so long as all the "accessors" of the named pipe are
> running on the same Linux machine with the NFS mount containing the pipe
> node, the named pipe works as expected (just tested this as well).

I tested it too (with an NFS v4.1 filesystem), and yes, mkfifo makes
a named pipe, and it works as expected.  (Didn't expect it to work
across machines, though that would be a neat trick.)


> But a named pipe on NFS does not give you a machine to machine (two
> different machines) transmit channel.
> 
>>>> As the demand grows, we are actually at the limits of performance
>>>> that even unnamed pipes gives us. So we are starting to migrate to
>>>> UNIX sockets which has about double to bandwidth and performance of
>>>> pipes.
>>> 
>>> Not sure how that works, given that Unix sockets are actually a more
>>> complex mechanism than pipes.
>> 
>> With Unix sockets, once the connection is made, it's all in-memory
>> networking.
> 
> Correct.
> 
>> I suspect (but don't know) that named pipes require the data to pass
>> through the filesystem for each write.
> 
> Incorrect.  The only 'filesystem' access for named pipes is during the
> open() call to look up the name from the filesystem.  Once you get the
> file descriptor back, it is the exact same in-memory FIFO queue as an
> anonymous pipe created via pipe() (at least on Linux).

Again, I stand corrected on that.

(Haven't figured out how to increase ulimit -p yet, doesn't seem
to want to increase, even as root...)

-- 
-v System76 Thelio Mega v1.1 x86_64 NVIDIA RTX 3090 Ti
   OS: Linux 6.12.0 Release: Mint 21.3 Mem: 258G
   "A good hot dog feeds the hand that bites it."

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Thread

Are We Back to the "Wars" Now ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-18 01:20 -0500
  Re: Are We Back to the "Wars" Now ? D <nospam@example.net> - 2024-11-18 10:13 +0100
    Re: Are We Back to the "Wars" Now ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-19 21:57 -0500
      Re: Are We Back to the "Wars" Now ? D <nospam@example.net> - 2024-11-20 10:01 +0100
  Re: Are We Back to the "Wars" Now ? Pancho <Pancho.Jones@proton.me> - 2024-11-18 09:27 +0000
  Re: Are We Back to the "Wars" Now ? Richard Kettlewell <invalid@invalid.invalid> - 2024-11-18 09:54 +0000
  Re: Are We Back to the "Wars" Now ? Rich <rich@example.invalid> - 2024-11-18 10:46 +0000
    Re: Are We Back to the "Wars" Now ? Phillip Frabott <nntp@fulltermprivacy.com> - 2024-11-18 09:45 -0500
      Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-20 00:23 +0000
        Re: Are We Back to the "Wars" Now ? Phillip Frabott <nntp@fulltermprivacy.com> - 2024-11-21 02:05 -0500
          Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-21 07:22 +0000
            Re: Are We Back to the "Wars" Now ? Phillip Frabott <nntp@fulltermprivacy.com> - 2024-11-21 10:12 -0500
              Re: Are We Back to the "Wars" Now ? Richard Kettlewell <invalid@invalid.invalid> - 2024-11-21 18:38 +0000
                Re: Are We Back to the "Wars" Now ? Phillip Frabott <nntp@fulltermprivacy.com> - 2024-11-21 21:55 -0500
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-22 03:12 +0000
                Re: Are We Back to the "Wars" Now ? vallor <vallor@cultnix.org> - 2024-11-22 06:09 +0000
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-22 06:37 +0000
                Re: Are We Back to the "Wars" Now ? vallor <vallor@cultnix.org> - 2024-11-22 07:02 +0000
                Named pipes vs. Unix sockets (was: Re: Are We Back to the "Wars" Now ?) vallor <vallor@cultnix.org> - 2024-11-22 07:29 +0000
                Re: Named pipes vs. Unix sockets vallor <vallor@cultnix.org> - 2024-11-22 08:38 +0000
                Re: Named pipes vs. Unix sockets Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-22 09:37 +0000
                Re: Named pipes vs. Unix sockets Phillip Frabott <nntp@fulltermprivacy.com> - 2024-11-22 10:00 -0500
                Re: Named pipes vs. Unix sockets Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-22 20:52 +0000
                Re: Named pipes vs. Unix sockets Phillip Frabott <nntp@fulltermprivacy.com> - 2024-11-22 17:06 -0500
                Re: Named pipes vs. Unix sockets Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-23 00:42 +0000
                Re: Named pipes vs. Unix sockets rlhamil@smart.net (Richard L. Hamilton) - 2024-12-03 05:23 +0000
                Re: Named pipes vs. Unix sockets Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-12-03 06:20 +0000
                Re: Are We Back to the "Wars" Now ? Rich <rich@example.invalid> - 2024-11-22 19:11 +0000
                Re: Are We Back to the "Wars" Now ? vallor <vallor@cultnix.org> - 2024-11-23 03:25 +0000
                Re: Are We Back to the "Wars" Now ? Rich <rich@example.invalid> - 2024-11-23 04:28 +0000
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-23 04:50 +0000
                Pipes v. FIFOs (was: Are We Back to the "Wars" Now ?) Geoff Clare <geoff@clare.See-My-Signature.invalid> - 2024-11-26 14:21 +0000
                Re: Are We Back to the "Wars" Now ? Richard Kettlewell <invalid@invalid.invalid> - 2024-11-22 10:04 +0000
              Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-21 21:56 +0000
                Re: Are We Back to the "Wars" Now ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-22 01:44 -0500
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-22 06:49 +0000
                Re: Are We Back to the "Wars" Now ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-22 23:44 -0500
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-23 05:19 +0000
                Re: Are We Back to the "Wars" Now ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-23 01:27 -0500
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-23 07:41 +0000
                Re: Are We Back to the "Wars" Now ? "Carlos E.R." <robin_listas@es.invalid> - 2024-11-23 14:39 +0100
                Re: Are We Back to the "Wars" Now ? Fritz Wuehler <fritz@spamexpire-202411.rodent.frell.theremailer.net> - 2024-11-23 22:32 +0100
                Re: Are We Back to the "Wars" Now ? "Carlos E.R." <robin_listas@es.invalid> - 2024-11-24 00:11 +0100
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-23 22:04 +0000
                Re: Are We Back to the "Wars" Now ? "Carlos E.R." <robin_listas@es.invalid> - 2024-11-24 00:11 +0100
                Re: Are We Back to the "Wars" Now ? The Natural Philosopher <tnp@invalid.invalid> - 2024-11-23 11:12 +0000
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-23 21:25 +0000
                Re: Are We Back to the "Wars" Now ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-23 19:42 -0500
                Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-24 02:03 +0000
                Re: Are We Back to the "Wars" Now ? Rich <rich@example.invalid> - 2024-11-24 14:25 +0000
                Re: Are We Back to the "Wars" Now ? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2024-11-24 15:48 +0000
                Re: Are We Back to the "Wars" Now ? Rich <rich@example.invalid> - 2024-11-24 16:56 +0000
                Re: Are We Back to the "Wars" Now ? Richard Kettlewell <invalid@invalid.invalid> - 2024-11-24 19:14 +0000
                Re: Are We Back to the "Wars" Now ? "Carlos E.R." <robin_listas@es.invalid> - 2024-11-24 20:32 +0100
                Re: Are We Back to the "Wars" Now ? Rich <rich@example.invalid> - 2024-11-24 19:36 +0000
  Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-11-20 00:22 +0000
    Re: Are We Back to the "Wars" Now ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-12-03 01:19 -0500
      Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-12-03 06:49 +0000
        Re: Are We Back to the "Wars" Now ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-12-04 01:10 -0500
          Re: Are We Back to the "Wars" Now ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-12-04 06:45 +0000

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