Sujet : Re: Are We Back to the "Wars" Now ?
De : invalid (at) *nospam* invalid.invalid (Richard Kettlewell)
Groupes : comp.os.linux.miscDate : 24. Nov 2024, 20:14:59
Autres entêtes
Organisation : terraraq NNTP server
Message-ID : <wwvldx8qw98.fsf@LkoBDZeT.terraraq.uk>
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User-Agent : Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux)
Lew Pitcher <
lew.pitcher@digitalfreehold.ca> writes:
On Sun, 24 Nov 2024 14:25:10 +0000, Rich wrote:
186282@ud0s4.net <186283@ud0s4.net> wrote:
On 11/23/24 4:25 PM, Lawrence D'Oliveiro wrote:
That’s irrelevant. Pipes originated on the earliest Unix machine,
which was a PDP-11 with only a 64kiB address space. They work great
for pumping around gigabytes of data, but you don’t need
gigabyte-sized memory buffers to do that.
It all has to be SOMEWHERE ... if not in RAM then
on a mass storage device.
Nope, at least not with pipes.
>
Hold on a sec.... pipes are /buffered/ in RAM, so there's at least
a small bit of ram set aside for each open pipe.
The word ‘all’ isn’t just decoration. The claim was ‘it all has to be
somewhere’, and Rich’s point (as I understand it) is that it does not
all have to be somewhere.
For example,
head -c $((1024*1024*1024)) /dev/urandom | sha256sum
puts a gigabyte of data through a pipe, but at no point does anything
allocate anywhere close to a gigabyte of storage of any kind.
-- https://www.greenend.org.uk/rjk/