Documentation

Default max streams. (64)

Default max data of a stream. (256K bytes)

Default max data of a connection.

By default, this is set to defaultMaxStreams * defaultMaxStreamData. This ensures that streams that are not currently handled cannot exhaust the connection window.

If you use a smaller connection window size, you must ensure that if you are handling fewer concurrent streams than allowed by defaultMaxStreams, that the unhandled streams cannot exhaust the connection window, or risk the entire system deadlocking.

Flow for sending

-------------------------------------->
       ^           ^
    txfSent    txfLimit

       |-----------| The size which this node can send
       txWindowSize

Creating TX flow with a receive buffer size.

txfLimit - txfSent.

Window size.

Flow for receiving.

The goal of RxFlow is to ensure that our network peer does not send us data faster than we can consume it. We therefore impose a maximum number of unconsumed bytes that we are willing to receive from the peer, which we refer to as the buffer size:

                   rxfBufSize
          |---------------------------|
-------------------------------------------->
          ^              ^
     rxfConsumed    rxvReceived

The peer does not know of course how many bytes we have consumed of the data that they sent us, so they keep track of their own limit of how much data they are allowed to send. We keep track of this limit also:

                   rxfBufSize
          |---------------------------|
-------------------------------------------->
          ^              ^       ^
     rxfConsumed    rxvReceived  |
                              rxfLimit

Each time we receive data from the peer, we check that they do not exceed the limit (checkRxLimit). When we consume data, we periodically send the peer an update (known as a _window update_) of what their new limit is (maybeOpenRxWindow). To decrease overhead, we only this if the window update is at least half the window size.

Creating RX flow with an initial window size.

rxfLimit - rxfReceived.

This is the number of bytes the peer is still allowed to send before they must wait for a window update; see RxFlow for details.

The representation of window size update.

Record that we have consumed some received data

May return a window update; see RxFlow for details.

Checking if received data is acceptable against the current window.

Sized cache based on least recently used.

Empty LRUCache. O(1)

Inserting. O(log n)

Deleting. O(log n)

Looking up. O(log n)

Looking up and changing priority. O(log n)

Empty LRUCache. O(1)

Type for rating.

Creating a new Rate.

Getting the current rate. If one or more seconds have passed since the previous call, the counter is re-initialized with 1 and it is returned. Otherwise, incremented counter number is returned.

Getting the current rate. If one or more seconds have passed since the previous call, the counter is re-initialized with the second argument and it is returned. Otherwise, increased counter number is returned.