Satisfy net.Conn about smux

[xtaci]

how to implement SetWriteDeadline(t time.Time) error for different streams on the same connection?

[AudriusButkevicius]

Well yamux does it somehow.

[xtaci]

but with problem

[AudriusButkevicius]

What problem?
I mean it's not feasible to have any networking library if you might end up hanging indefinately or for unreasonable amounts of time (say 30 seconds on a handshake)

[AudriusButkevicius]

As for implementation it's trivial, all the deadlines do is promise that next calls will not block for longer than X, no other sematics are implied by that.

[xtaci]

you have to set the underlying connection's WriteDeadLine to the closest one of all streams, or else, it will block when sockbuf is full.

so a possible solution is by maintaining a min-heap for deadline. when the closest deadline has reached, switch to the next one.

[AudriusButkevicius]

I think it's perfectly fine to discard data at some later point (after the write has returned), the idea is just not to block on the write for too long, if the send queue is full or something like that.

[xtaci]

you can't guarantee that if you do not set write deadline to for example TCPConn.

[AudriusButkevicius]

Well I suspect it's fine for the dispatching routine to block indefinately or to maintain a continious 1s deadline itself internally, yet it doesn't need to be related to the deadline of the stream.

[AudriusButkevicius]

I guess you need a deadline for Accept() on the session for example.

[xtaci]

continuous 1s interrupt doesn't guarantee the atomicity of conn.Write for various underlying connections , you have to handle 'wrote incomplete data' problem, especially for TCPConn.

[AudriusButkevicius]

Fine, you can probably get away without a deadline there as the write call would return upon a close of tye connection anyway, not causing any routine leaks.