Re: [PATCH] net_sched: accurate bytes/packets stats/rates
flat view
From: Jarek Poplawski <hidden>
Date: 2011-01-16 22:35:47
On Fri, Jan 14, 2011 at 11:03:42AM -0800, Stephen Hemminger wrote:
From Eric Dumazet [off-list ref] In commit 44b8288308ac9d (net_sched: pfifo_head_drop problem), we fixed a problem with pfifo_head drops that incorrectly decreased sch->bstats.bytes and sch->bstats.packets Several qdiscs (CHOKe, SFQ, pfifo_head, ...) are able to drop a previously enqueued packet, and bstats cannot be changed, so bstats/rates are not accurate (over estimated) This patch changes the qdisc_bstats updates to be done at dequeue() time instead of enqueue() time. bstats counters no longer account for dropped frames, and rates are more correct, since enqueue() bursts dont have effect on dequeue() rate. Signed-off-by: Eric Dumazet <redacted> Acked-by: Stephen Hemminger <redacted> CC: Patrick McHardy <redacted> CC: Jarek Poplawski <redacted> CC: jamal <redacted>
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quoted hunk ↗ jump to hunk
--- a/net/sched/sch_drr.c 2011-01-14 09:19:00.830857886 -0800 +++ b/net/sched/sch_drr.c 2011-01-14 09:28:20.398631228 -0800@@ -376,7 +376,6 @@ static int drr_enqueue(struct sk_buff *s } bstats_update(&cl->bstats, skb);
Why leave leaf classes with different stats? Jarek P.
quoted hunk ↗ jump to hunk
- qdisc_bstats_update(sch, skb); sch->q.qlen++; return err;
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