[PATCH] burstable dummynet pipe

Luigi Rizzo rizzo at icir.org
Tue Nov 2 22:38:38 PST 2004


On Sun, Oct 31, 2004 at 09:35:58PM +0100, Pawel Malachowski wrote:
> Hello,
> 
> Attached (poor) patch (against 5.3-RC1) implements pipes that can be
> overloaded (exceed their bw) for a (short) period of time.
> It adds yet another parameter for pipe: `burst x', x in (K)Bytes.
> Should also work with dynamic (clonable via mask) pipes.
> 
> Configuring `x bytes burst' means we are allowing to transmit x bytes
> with increased (by default: ~2x) speed. After that, traffic passes
> through pipe as usual (bw-limited), however, burst credit is slowly
> (by default: ~10x lower than bw) accumulated when pipe is idle (low

to tell the truth, the 2x and 10x thing seems to me a rather
kludgy and arbitrary way to implement 'bursts'.
The most straightforward way to implement this feature is
to let the pipe be "burst" bytes ahead of the programmed rate,
which results in a rather trivial change to the current code.
If you really want to burst out data and recover credt at a
different rate, these extra rates should be configurable.

so if someone thinks of committing this patch in the current form,
please at least note in the commit log that i am opposed to that.

cheers
luigi


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