Re: Linux iSCSI Initiator, OpenSource (fwd) (Re: Gauntlet Set NOW!)

From: Valdis.Kletnieks@vt.edu
Date: Tue Jan 07 2003 - 03:00:14 EST


On Tue, 07 Jan 2003 04:08:29 -0300, Werner Almesberger said:
> Valdis.Kletnieks@vt.edu wrote:

> > it takes *hours* without a
> > packet drop to get the window open *all* the way
>
> Or did you mean "after" instead of "without" ? Or maybe "into
> equilibrium" instead of "the window open ..." ? (After all, the
> window isn't only open, but it's been blown off its hinges.)

"without". Let's say it takes 4 hours to recover from a drop, and
you have another one 3 hours into recovery - it will now take more than
one more hour to recover.

"into equilibrium fully open". It's easy enough to see it in equilibrium
(more or less) not fully open.. ;)

> In any case, your statement accurately describes a somewhat
> surprising quirk in Linux TCP performance as of only a bit more
> than six years ago :)

OK, I tuned in late - are you saying that the 6-year-old Linux quirk
happened to have the same symptoms as Floyd's current work, or that
the slow-start tweaks were designed in 6 years ago, or that a fix for
the quirk accidentally did the same thing as Floyd's stuff?

The whole slow-start/ack/retransmit has been chewed over so many times in the
last 20 years that it's hard to keep track of which vendors picked up which
tweaks when, and which vendors accidentally invented them again, and which
vendors invented the tweaks independently and didn't publicize them more....

/Valdis



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Tue Jan 07 2003 - 22:00:34 EST