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benchmarkingload-testingserver-sent-events

How to load test Server Sent Events?

I have a small app that sends Server Sent Events. I would like to load test my app so I can benchmark the latency from the time a message is pushed to the time the message is received so I can know when/where the performance breaks down. What tools are available to be able to do this?

Solution

  • Since Server-Sent Events it is just HTTP you can use siege utility. Here is the example:

    siege -b -t 1m -c45 http://127.0.0.1:9292/streaming

    Where:

    • -b benchmark mode i.e. don't wait between connections
    • -t 1m benchmark for 1 minute
    • -c45 number of concurrent connections
    • http://127.0.0.1:9292 my dev server host and custom port
    • /streaming HTTP-endpoint which respond with Content-Type: text/event-stream

    Output:

    Lifting the server siege...      done.

Transactions:                 79 hits
Availability:             100.00 %
Elapsed time:              59.87 secs
Data transferred:           0.01 MB
Response time:             23.43 secs
Transaction rate:           1.32 trans/sec
Throughput:             0.00 MB/sec
Concurrency:               30.91
Successful transactions:          79
Failed transactions:               0
Longest transaction:           30.12
Shortest transaction:          10.04