[Bloat] SO_SNDBUF and SO_RCVBUF
Steinar H. Gunderson
sgunderson at bigfoot.com
Wed Apr 22 15:11:54 PDT 2015
On Wed, Apr 22, 2015 at 02:42:59PM -0700, Eric Dumazet wrote:
> Sorry, I do not understand you.
>
> The nice thing about TCP_NOTSENT_LOWAT is that you no longer have to
> care about choosing the 'right SO_SNDBUF'
>
> It is still CC responsibility to choose/set cwnd, but you hadn't set an
> artificial cap on cwnd.
>
> You control the amount of 'unsent data' per socket.
>
> If you set a low limit, application might have to issue more send()
> calls and get more EPOLLOUT events.
>
> This also means that if you get an abort / eof, you no longer have a
> huge unsent queue that TCP API does not allow to cancel.
>
> https://insouciant.org/tech/prioritization-only-works-when-theres-pending-data-to-prioritize/
So this URL is basically what I said; you need to have data to prioritize
between for this to be useful. If you just want to send a simple file
(and aborts in HTTP/1.1 basically don't really exist), it doesn't really
matter if you have a huge backlog or not.
So I'm sure it's useful for HTTP/2 or SPDY, but that's already pretty
advanced functionality.
/* Steinar */
--
Homepage: http://www.sesse.net/
More information about the Bloat
mailing list