Re: STREAMS: interface versus implementation

Alan Cox (alan@lxorguk.ukuu.org.uk)
Wed, 16 Sep 1998 15:54:08 +0100 (BST)


> > Just overload the ioctl symbol
>
> That stinks. While nobody expects STREAMS to be really fast,
> they shouldn't add severe overhead to libc. That includes the
> non-STREAMS part of an application that uses STREAMS.

Tragedy.

1. Anyone who needed that performance wouldnt be using streams they'd
be rewriting.
2. It only affects anything linked with said streams library.
3. The "severe overhead argument" is complete shit. You are
adding

if(*(u32 *)pathname='/dev')

to most opens. 2 clocks at most with branch prediction in
your favour and about 5 or 6 additional long sized comparisons
for the slow path.

That will be lost in the noise after you've opened your first
emulated stream.

Alan

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