From: Fred Klassen <fklassen@appneta.com>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>,
Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
Shuah Khan <shuah@kernel.org>,
Network Development <netdev@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
linux-kselftest@vger.kernel.org,
Willem de Bruijn <willemb@google.com>
Subject: Re: [PATCH net 4/4] net/udpgso_bench_tx: audit error queue
Date: Tue, 28 May 2019 09:57:35 -0700 [thread overview]
Message-ID: <9811659B-6D5A-4C4F-9CF8-735E9CA6DE4E@appneta.com> (raw)
In-Reply-To: <CAF=yD-Le0XKCfyDBvHmBRVqkwn1D6ZoG=12gss5T62VcN5+1_w@mail.gmail.com>
> On May 28, 2019, at 8:08 AM, Willem de Bruijn <willemdebruijn.kernel@gmail.com> wrote:
>
I will push up latest patches soon.
I did some testing and discovered that only TCP audit tests failed. They
failed much less often when enabling poll. Once in about 20 runs
still failed. Therefore I commented out the TCP audit tests.
As for the other tests, this is what I got with poll() disabled…
udp gso zerocopy timestamp audit
udp rx: 1611 MB/s 1148129 calls/s
udp tx: 1659 MB/s 28146 calls/s 28146 msg/s
udp rx: 1686 MB/s 1201494 calls/s
udp tx: 1685 MB/s 28579 calls/s 28579 msg/s
udp rx: 1685 MB/s 1200402 calls/s
udp tx: 1683 MB/s 28552 calls/s 28552 msg/s
Summary over 3.000 seconds...
sum udp tx: 1716 MB/s 85277 calls (28425/s) 85277 msgs (28425/s)
Tx Timestamps: 85277 received 0 errors
Zerocopy acks: 85277 received 0 errors
Here you see that with poll() enabled, it is a bit slower, so I don’t have it
enabled in udpgso_bench.sh …
udp gso zerocopy timestamp audit
udp rx: 1591 MB/s 1133945 calls/s
udp tx: 1613 MB/s 27358 calls/s 27358 msg/s
udp rx: 1644 MB/s 1171674 calls/s
udp tx: 1643 MB/s 27869 calls/s 27869 msg/s
udp rx: 1643 MB/s 1170666 calls/s
udp tx: 1641 MB/s 27845 calls/s 27845 msg/s
Summary over 3.000 seconds...
sum udp tx: 1671 MB/s 83072 calls (27690/s) 83072 msgs (27690/s)
Tx Timestamps: 83072 received 0 errors
Zerocopy acks: 83072 received 0 errors
You may be interested that I reduced test lengths from 4 to 3 seconds,
but I am still getting 3 reports per test. I picked up the extra report by
changing 'if (tnow > treport)’ to 'if (tnow >= treport)’
> The only issue specific to GSO is that xmit_more can forego this
> doorbell until the last segment. We want to complicate this logic with
> a special case based on tx_flags. A process that cares should either
> not use GSO, or the timestamp should be associated with the last
> segment as I've been arguing so far.
This is the area I was thinking of looking into. I’m not sure it will work
or that it will be too messy. It may be worth a little bit of digging to
see if there is anything there. That will be down the road a bu
>>
>> I’ll get back to you when I have tested this more thoroughly. Early results
>> suggest that adding the -P poll() option has fixed it without any appreciable
>> performance hit. I’ll share raw results with you, and we can make a final
>> decision together.
>
> In the main loop? It still is peculiar that notifications appear to go
> missing unless the process blocks waiting for them. Nothing in
> sock_zerocopy_callback or the queueing onto the error queue should
> cause drops, as far as I know.
>
Now that I know the issue is only in TCP, I can speculate that all bytes are
being reported, but done with fewer messages. It may warrant some
investigation in case there is some kind of bug.
> Indeed. Ideally even run all tests, but return error if any failed,
> like this recent patch
>
> selftests/bpf: fail test_tunnel.sh if subtests fail
> https://patchwork.ozlabs.org/patch/1105221/
>
> but that may be a lot of code churn and better left to a separate patch.
I like it. I have it coded up, and it seems to work well. I’ll make a
separate commit in the patch set so we can yank it out if you feel
it is too much
next prev parent reply other threads:[~2019-05-28 16:57 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-23 21:06 [PATCH net 0/4] Allow TX timestamp with UDP GSO Fred Klassen
2019-05-23 21:06 ` [PATCH net 1/4] net/udp_gso: " Fred Klassen
2019-05-23 21:39 ` Willem de Bruijn
2019-05-24 1:38 ` Fred Klassen
2019-05-24 4:53 ` Willem de Bruijn
2019-05-24 16:34 ` Fred Klassen
2019-05-24 19:29 ` Willem de Bruijn
2019-05-24 22:01 ` Fred Klassen
2019-05-25 15:20 ` Willem de Bruijn
2019-05-25 18:47 ` Fred Klassen
2019-05-27 1:30 ` Willem de Bruijn
2019-05-27 2:09 ` Willem de Bruijn
2019-05-25 20:46 ` Fred Klassen
2019-05-23 21:59 ` Willem de Bruijn
2019-05-25 20:09 ` Fred Klassen
2019-05-25 20:47 ` Fred Klassen
2019-05-23 21:06 ` [PATCH net 2/4] net/udpgso_bench_tx: options to exercise TX CMSG Fred Klassen
2019-05-23 21:45 ` Willem de Bruijn
2019-05-23 21:52 ` Willem de Bruijn
2019-05-24 2:10 ` Fred Klassen
2019-05-23 21:06 ` [PATCH net 3/4] net/udpgso_bench_tx: fix sendmmsg on unconnected socket Fred Klassen
2019-05-23 21:06 ` [PATCH net 4/4] net/udpgso_bench_tx: audit error queue Fred Klassen
2019-05-23 21:56 ` Willem de Bruijn
2019-05-24 1:27 ` Fred Klassen
2019-05-24 5:02 ` Willem de Bruijn
2019-05-27 21:30 ` Fred Klassen
2019-05-27 21:46 ` Willem de Bruijn
2019-05-27 22:56 ` Fred Klassen
2019-05-28 1:15 ` Willem de Bruijn
2019-05-28 5:19 ` Fred Klassen
2019-05-28 15:08 ` Willem de Bruijn
2019-05-28 16:57 ` Fred Klassen [this message]
2019-05-28 17:07 ` Willem de Bruijn
2019-05-28 17:11 ` Willem de Bruijn
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=9811659B-6D5A-4C4F-9CF8-735E9CA6DE4E@appneta.com \
--to=fklassen@appneta.com \
--cc=davem@davemloft.net \
--cc=kuznet@ms2.inr.ac.ru \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=shuah@kernel.org \
--cc=willemb@google.com \
--cc=willemdebruijn.kernel@gmail.com \
--cc=yoshfuji@linux-ipv6.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).