Re: [PATCH] mac80211: retry sending failed BAR frames later instead of tearing down aggr

On 2011-08-31 2:15 PM, Johannes Berg wrote:

On Sun, 2011-08-28 at 21:11 +0200, Felix Fietkau wrote:

quoted

 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...

I think it mostly happens when the client goes to powersave (triggered 
by background scans, etc).

quoted

 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?

If it keeps failing, then the connection is probably so bad that it 
doesn't matter if we kill the session or not.

- Felix