Re: Sftp: performance enhancing changes

[Markus Friedl <markus%openbsd.org@localhost>]

On Fri, Sep 05, 2003 at 11:04:17AM -0600, Joseph Galbraith wrote:
> We had a discussion of sftp performance.  I don't
> think we really reached an consensus about a change.
> 
> The following things were brought up:
> 
> o Ignoring channel window makes for a screaming
>   sftp transfer. (unacceptable, breaks multiplexing.)
> 
> o I proposed a new SSH_FXP_MULTI_READ that would make
>   it easier to do large data transfers.
> 
> o An implementation hints section with some verbage
>   about issuing multiple simultaneous read and write
>   requests to obtain maxmimum performance.
> [...]
> So, what do we want to do?

ignoring the channel window is a very very bad suggestion.
annoucements of larger windows is a much better idea.

multi-read is not really necessary.

an implementation hint should help.  openssh's sftp performance has
increased considerably after Damien added support for multiple
simultaneous requests.