Gentlemen,

On Nov 8, 2007 1:20 PM, Michel Loiseleur <mloiseleur_at_linagora.com> wrote:

> Le Monday 05 November 2007 18:16:15 Michel Loiseleur, vous avez écrit:
> > Hi all,
> >
> > After my post here :
> >
> https://sourceforge.net/tracker/?func=detail&atid=100976&aid=1826056&group_
> >id=976
> >
> > I have reworked a little the patch, according to the comment. Feel
> free
> > to improve it, hack it and especially, integrate it :).
> >
> > In one sentence, this patch add a small feature to curl during ftp
> > transfer : it sends "NOOP" message in order to keep connection alive.
> >
>
> To the contrary, the SO_KEEPALIVE approach is working well. The patch
> is
> nonintrusive and do not force us to add some more flags or more options on
> compile time.
>
> Here is the sysctl call :
> $ sudo sysctl -w sysctl -w net.ipv4.tcp_keepalive_time=x
>

Sure, it works.

However, there are certain doubts with regards to its non-intrusiveness.
The default TCP KA timeout is about 2 hours. When you change it to some
seconds,
all TCP connections at the host will start using it
(and generate a certain CPU engagement).

My strong feeling is that correction of the host-wide TCP-stack parameters
is not a business of any application or a protocol stack, unless the whole
host
is devoted to that application/stack; it should be done by the host admin
explicitly.

This is jm2c ...

-- 
Sincerely,
Robert Iakobashvili,
coroberti %x40 gmail %x2e com
...........................................................
http://curl-loader.sourceforge.net
A web testing and traffic generation tool.