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Subject: Re: [PATCH] mac80211: retry sending failed BAR frames later
 instead of tearing down aggr
From: Johannes Berg <johannes@sipsolutions.net>
To: Felix Fietkau <nbd@openwrt.org>
Cc: linux-wireless@vger.kernel.org, linville@tuxdriver.com,
	Helmut Schaa <helmut.schaa@googlemail.com>
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Date: Wed, 31 Aug 2011 14:15:48 +0200
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On Sun, 2011-08-28 at 21:11 +0200, Felix Fietkau wrote:
> Unfortunately failed BAR tx attempts happen more frequently than I
> expected, and the resulting aggregation teardowns cause performance
> issues, as the aggregation session does not always get re-established
> properly.

I find this curious. How can tons of traffic go through, but BAR frames
fail? These are unicast and should be retried a bunch...

> Instead of tearing down the entire aggr session, we can simply store the
> SSN of the last failed BAR tx attempt, wait for the first successful
> tx status event, and then send another BAR with the same SSN.

So what if it keeps failing? I think eventually we'd want to kill the
session?

johannes