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[CCID2]: Disable broken Ack Ratio adaptation algorithm

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This comments out a problematic section comprising a half-finished algorithm:

 - The variable `ccid2hctx_ackloss' is never initialised to a value different from 0 and
   hence in fact is a read-only constant.
 - The `arsent' variable counts packets other than Acks (it is incremented for every packet),
   and there is no test for Ack Loss.
 - The concept of counting Acks as such leads to a complex calculation, and the calculation
   at the moment is inconsistent with this concept.
   The problem is that the number of Acks - rather than the number of windows - is counted,
   which leads to a complex (cubic/quadratic) expression - this is not even implemented.

In its current state, the commented-out algorithm interfers with normal processing by
changing Ack Ratio incorrectly, and at the wrong times.

A new algorithm is necessary, which will not necessarily use the same variables as used by
the unfinished one; hence the old variables have been removed.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Gerrit Renker
2007-11-24 21:58:33 -02:00
committed by David S. Miller
parent b00d2bbc45
commit 900bfed471
2 changed files with 21 additions and 6 deletions
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4
net/dccp/ccids/ccid2.h
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@@ -44,8 +44,6 @@ struct ccid2_seq {
* @ccid2hctx_acks - ACKS recv in AI phase
* @ccid2hctx_sent - packets sent in this window
* @ccid2hctx_lastrtt -time RTT was last measured
* @ccid2hctx_arsent - packets sent [ack ratio]
* @ccid2hctx_ackloss - ack was lost in this win
* @ccid2hctx_rpseq - last consecutive seqno
* @ccid2hctx_rpdupack - dupacks since rpseq
*/
@@ -66,8 +64,6 @@ struct ccid2_hc_tx_sock {
int ccid2hctx_sent;
unsigned long ccid2hctx_lastrtt;
struct timer_list ccid2hctx_rtotimer;
unsigned long ccid2hctx_arsent;
int ccid2hctx_ackloss;
u64 ccid2hctx_rpseq;
int ccid2hctx_rpdupack;
int ccid2hctx_sendwait;