scheduling off the waiting list

Poul-Henning Kamp phk at
Mon Dec 28 22:24:08 CET 2009

In message <4B39210F.7080908 at>, Nils Goroll writes:

>So basically there are two different scenarios when hsh_rush is called.
>* Trigger delivery of an object which just got unbusied
>* and trigger delivery of more sessions which did not fire in the first round

The basic point here is that we do not want to unleash 500 waiting sessions
when the object is unbusied, so we release a few, and when they are done
they each release a few etc.

Sort of inspired by TCP-slowstart, but not half as advanced.

I'm not entirely happy with how this works in practice, but within the
current reach, I have no better ideas.

Grace mode helps a lot, if you can use it.


Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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