[Spice-devel] [PATCH v2 spice-protocol 2/2] Add qos related messages

[Marc-André Lureau]

On Thu, Apr 19, 2012 at 9:30 AM, Yonit Halperin <yhalperi at redhat.com> wrote:
> The latency factor is in my TODO (see cover letter).
> I use ioctl(socket, TIOCOUTQ) in order to find how many bytes are pending in
> the tcp snd buffer, in addition to the size of the message.
> So I calculate the bandwidth by (message_size + ioctl(socket,
> TIOCOUTQ))/ack_time.
> When I add the latency, it will be (message_size + ioctl(socket, TIOCOUTQ))
> / (ack_time - latency)
>
> This measurement can be affected by other links, but I think it is what we
> want -> the actual bandwidth available for the channel.

Don't we want to measure only downlink bandwidth/conditon separately
from uplink? What you suggest takes into account a lot of parameters
from both side. I still fail to see what exactly it represents. Imho,
it doesn't need TIOCOUTQ or latency. A top with N bytes sent "in
burst" is all it takes, no?


-- 
Marc-André Lureau