Bug 74051

Summary:	[BISECTED]TUN device performance regression
Product:	Networking	Reporter:	Martin Filip (nexus+kernel)
Component:	Other	Assignee:	Stephen Hemminger (stephen)
Status:	NEW ---
Severity:	high	CC:	alan, arthur.titeica, buitrongnhan.iphone, bvanassche, daniel, gert, jed-kernel.org, szg00000
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	v3.15-rc1	Subsystem:
Regression:	Yes	Bisected commit-id:
Attachments:	git bisect log huu

Description Martin Filip 2014-04-14 10:50:35 UTC

I've noticed significant TUN device performance drop between 3.13 and 3.14 kernels, problem seems to persist until current git version.

With good kernel I can achieve full 100mbps through openvpn without any problem, with problematic kernel TX performance drops down to ~50kbps.

According to git bisect it seems that root of all evil is commit 53d6471cef17262d3ad1c7ce8982a234244f68ec.

I can confirm that performance is great again with current kernel when I revert this one.

Comment 1 Martin Filip 2014-04-14 10:51:22 UTC

Created attachment 132161 [details]
git bisect log

Comment 2 Daniel Borkmann 2014-04-14 10:56:14 UTC

Please report all of that to netdev@vger.kernel.org thanks.

Comment 3 Martin Filip 2014-04-23 07:22:07 UTC

Fix was merged as 1e785f48d29a09b6cf96db7b49b6320dada332e1

Comment 4 Bart Van Assche 2014-05-11 09:07:44 UTC

Duplicate of https://bugzilla.kernel.org/show_bug.cgi?id=73891.

Comment 5 huu 2016-07-18 22:00:11 UTC

Created attachment 224231 [details]
huu