From: David Laight <David.Laight@ACULAB.COM>
To: 'Eric Dumazet' <eric.dumazet@gmail.com>,
'Paolo Abeni' <pabeni@redhat.com>,
Jesper Dangaard Brouer <brouer@redhat.com>
Cc: 'Marek Majkowski' <marek@cloudflare.com>,
linux-kernel <linux-kernel@vger.kernel.org>,
network dev <netdev@vger.kernel.org>,
kernel-team <kernel-team@cloudflare.com>
Subject: RE: epoll_wait() performance
Date: Thu, 28 Nov 2019 10:17:34 +0000 [thread overview]
Message-ID: <1265e30d04484d08b86ba2abef5f5822@AcuMS.aculab.com> (raw)
In-Reply-To: <313204cf-69fd-ec28-a22c-61526f1dea8b@gmail.com>
From: Eric Dumazet
> Sent: 27 November 2019 17:47
...
> A QUIC server handles hundred of thousands of ' UDP flows' all using only one UDP socket
> per cpu.
>
> This is really the only way to scale, and does not need kernel changes to efficiently
> organize millions of UDP sockets (huge memory footprint even if we get right how
> we manage them)
>
> Given that UDP has no state, there is really no point trying to have one UDP
> socket per flow, and having to deal with epoll()/poll() overhead.
How can you do that when all the UDP flows have different destination port numbers?
These are message flows not idempotent requests.
I don't really want to collect the packets before they've been processed by IP.
I could write a driver that uses kernel udp sockets to generate a single message queue
than can be efficiently processed from userspace - but it is a faff compiling it for
the systems kernel version.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
next prev parent reply other threads:[~2019-11-28 10:17 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-22 11:17 epoll_wait() performance David Laight
2019-11-27 9:50 ` Marek Majkowski
2019-11-27 10:39 ` David Laight
2019-11-27 15:48 ` Jesper Dangaard Brouer
2019-11-27 16:04 ` David Laight
2019-11-27 19:48 ` Willem de Bruijn
2019-11-28 16:25 ` David Laight
2019-11-28 11:12 ` Jesper Dangaard Brouer
2019-11-28 16:37 ` David Laight
2019-11-28 16:52 ` Willy Tarreau
2019-12-19 7:57 ` Jesper Dangaard Brouer
2019-11-27 16:26 ` Paolo Abeni
2019-11-27 17:30 ` David Laight
2019-11-27 17:46 ` Eric Dumazet
2019-11-28 10:17 ` David Laight [this message]
2019-11-30 1:07 ` Eric Dumazet
2019-11-30 13:29 ` Jakub Sitnicki
2019-12-02 12:24 ` David Laight
2019-12-02 16:47 ` Willem de Bruijn
2019-11-27 17:50 ` Paolo Abeni
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