Flent-users discussion archives
 help / color / mirror / Atom feed
* Re: [Flent-users] [tohojo/flent] flent on newer versions of Linux (#157)
       [not found] <tohojo/flent/issues/157@github.com>
@ 2018-12-31 20:31 ` Toke Høiland-Jørgensen
  2019-01-08 11:10 ` Toke Høiland-Jørgensen
  2019-01-09 11:51 ` Toke Høiland-Jørgensen
  2 siblings, 0 replies; 3+ messages in thread
From: Toke Høiland-Jørgensen @ 2018-12-31 20:31 UTC (permalink / raw)
  To: tohojo/flent; +Cc: Subscribed


[-- Attachment #1.1: Type: text/plain, Size: 919 bytes --]

Leslie Monis <notifications@github.com> writes:

> Hi,
>
> I have encountered an issue when running the tcp_nup tests on newer
> versions of Linux, specifically v4.16 and up. It seems that flent
> isn't able to get enough data points (for upload throughput) for
> individual TCP flows. This is causing the median TCP upload sum value
> to be way lower than the the average TCP upload sum on a setup with a
> bottleneck bandwidth of 10 Mbits/s. Whereas, the same setup, with
> flent running on a slightly older version of Linux (v4.13 and v4.15)
> gives results with good number of data points for individual TCP
> flows.

Can you supply a debug log file (-L to Flent) and the data file being
produced when you run into this issue?


-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/tohojo/flent/issues/157#issuecomment-450688043

[-- Attachment #1.2: Type: text/html, Size: 3412 bytes --]

[-- Attachment #2: Type: text/plain, Size: 151 bytes --]

_______________________________________________
Flent-users mailing list
Flent-users@flent.org
http://flent.org/mailman/listinfo/flent-users_flent.org

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [Flent-users] [tohojo/flent] flent on newer versions of Linux (#157)
       [not found] <tohojo/flent/issues/157@github.com>
  2018-12-31 20:31 ` [Flent-users] [tohojo/flent] flent on newer versions of Linux (#157) Toke Høiland-Jørgensen
@ 2019-01-08 11:10 ` Toke Høiland-Jørgensen
  2019-01-09 11:51 ` Toke Høiland-Jørgensen
  2 siblings, 0 replies; 3+ messages in thread
From: Toke Høiland-Jørgensen @ 2019-01-08 11:10 UTC (permalink / raw)
  To: tohojo/flent; +Cc: Subscribed


[-- Attachment #1.1: Type: text/plain, Size: 509 bytes --]

Hmm, I think this could be caused by this commit:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0a6b2a1dc2a2105f178255fe495eb914b09cb37a

...which makes TCP always use GSO.

This was introduced in Linux 4.17; is there any chance you could test that the difference appeared in that version?

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/tohojo/flent/issues/157#issuecomment-452261743

[-- Attachment #1.2: Type: text/html, Size: 2577 bytes --]

[-- Attachment #2: Type: text/plain, Size: 151 bytes --]

_______________________________________________
Flent-users mailing list
Flent-users@flent.org
http://flent.org/mailman/listinfo/flent-users_flent.org

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [Flent-users] [tohojo/flent] flent on newer versions of Linux (#157)
       [not found] <tohojo/flent/issues/157@github.com>
  2018-12-31 20:31 ` [Flent-users] [tohojo/flent] flent on newer versions of Linux (#157) Toke Høiland-Jørgensen
  2019-01-08 11:10 ` Toke Høiland-Jørgensen
@ 2019-01-09 11:51 ` Toke Høiland-Jørgensen
  2 siblings, 0 replies; 3+ messages in thread
From: Toke Høiland-Jørgensen @ 2019-01-09 11:51 UTC (permalink / raw)
  To: tohojo/flent; +Cc: Subscribed


[-- Attachment #1.1: Type: text/plain, Size: 647 bytes --]

Leslie Monis <notifications@github.com> writes:

>> Hmm, I think this could be caused by this commit:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0a6b2a1dc2a2105f178255fe495eb914b09cb37a
>>
>>...which makes TCP always use GSO.
>
> Yes, the commit does seem to cause the issue.

Great, thanks for confirming! Now, the question is what can be done
about it; I'll poke around a bit and see if I can come up with a
workaround.


-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/tohojo/flent/issues/157#issuecomment-452670046

[-- Attachment #1.2: Type: text/html, Size: 2828 bytes --]

[-- Attachment #2: Type: text/plain, Size: 151 bytes --]

_______________________________________________
Flent-users mailing list
Flent-users@flent.org
http://flent.org/mailman/listinfo/flent-users_flent.org

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2019-01-09 11:51 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <tohojo/flent/issues/157@github.com>
2018-12-31 20:31 ` [Flent-users] [tohojo/flent] flent on newer versions of Linux (#157) Toke Høiland-Jørgensen
2019-01-08 11:10 ` Toke Høiland-Jørgensen
2019-01-09 11:51 ` Toke Høiland-Jørgensen

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox