Multiple-speed message channel of messaging system

1. A method, comprising:

storing messages of a channel of a plurality of channels in one or more buffers according to an order, wherein each buffer comprises a respective time-to-live;

for one or more connections, determining, by one or more computer processors, a respective sampling rate based on one of a data type of the channel and a determined latency of each connection;

receiving a request for messages of the channel from a subscriber through a connection of the one or more connections;

selecting messages from the one or more buffers according to the sampling rate; and

sending the selected messages to the subscriber according to the order using the connection.

2. The method of claim 1 , comprising:

receiving messages of the channel from a plurality of publishers.

3. The method of claim 2 , wherein the order comprises the order in which messages of the channel were received.

4. The method of claim 1 , wherein determining the respective sampling rate based on the data type of the channel comprises:

identifying a time-varying data field in messages of the channel;

obtaining respective data values in the time-varying data field from two or more messages of the channel; and

determining a magnitude of changes in the respective data values with respect to time to determine the respective sampling rate for each connection.

5. The method of claim 1 , wherein determining the respective sampling rate based on the data type of the channel comprises:

identifying one or more messages of the channel having a prioritized message data type, wherein sampling does not skip messages having the prioritized message data type for delivery to the subscriber.

6. The method of claim 1 , comprising:

determining the latency of the connection based on an indication of at least one of a delay and a missing delivery to the subscriber of one or more messages of the channel.

7. The method of claim 6 , wherein the indication is received from the subscriber.

8. The method of claim 1 , comprising:

determining the latency of the connection based on an indication of at least one of a delay and a missing delivery to the subscriber of one or more messages of another channel of the plurality of channels.

9. The method of claim 1 , comprising:

determining a second latency of the connection; and

adjusting the sampling rate for the connection based on the second latency.

10. The method of claim 1 , wherein messages are selected from the one or more buffers that have not expired.

11. A system, comprising:

one or more computer processors programmed to:

store messages of a channel of a plurality of channels in one or more buffers according to an order, wherein each buffer comprises a respective time-to-live;

for one or more connections, determine a respective sampling rate based on one of a data type of the channel and a determined latency of each connection;

receive a request for messages of the channel from a subscriber through a connection of the one or more connections;

select messages from the one or more buffers according to the sampling rate; and

send the selected messages to the subscriber according to the order using the connection.

12. The system of claim 11 , wherein the one or more computer processors further programmed to receive messages of the channel from a plurality of publishers.

13. The system of claim 12 , wherein the order comprises the order in which messages of the channel were received.

14. The system of claim 11 , wherein to determine the respective sampling rate based on the data type of the channel, the one or more computer processors are programmed to:

identify a time-varying data field in messages of the channel;

obtain respective data values in the time-varying data field from two or more messages of the channel; and

determine a magnitude of changes in the respective data values with respect to time to determine the respective sampling rate for each connection.

15. The system of claim 11 , wherein to determine the respective sampling rate based on the data type of the channel, the one or more computer processors are programmed to:

identify one or more messages of the channel having a prioritized message data type, wherein sampling does not skip messages having the prioritized message data type for delivery to the subscriber.

16. The system of claim 11 , wherein the one or more computer processors further programmed to:

determine the latency of the connection based on an indication of at least one of a delay and a missing delivery to the subscriber of one or more messages of the channel.

17. The system of claim 11 , wherein the one or more computer processors further programmed to:

determine the latency of the connection based on an indication of at least one of a delay and a missing delivery to the subscriber of one or more messages of another channel of the plurality of channels.

18. The system of claim 11 , wherein one or more computer processors further programmed to:

determine a second latency of the connection; and

adjust the sampling rate for the connection based on the second latency.

19. The system of claim 11 , wherein messages are selected from the one or more buffers that have not expired.

20. A non-transitory computer-readable medium having instructions stored thereon that, when executed by one or more computer processors, cause the one or more computer processors to:

store messages of a channel of a plurality of channels in one or more buffers according to an order, wherein each buffer comprises a respective time-to-live;

for one or more connections, determine, by the one or more computer processors, a respective sampling rate based on one of a data type of the channel and a determined latency of each connection;

receive a request for messages of the channel from a subscriber through a connection of the one or more connections;

select messages from the one or more buffers according to the sampling rate; and

send the selected messages to the subscriber according to the order using the connection.