Benchmarks have been ran with the following versions of modules.

├── async@1.5.0
├── babel@5.8.29
├── davy@1.0.1
├── deferred@0.7.3
├── kew@0.7.0
├── lie@3.0.1
├── neo-async@1.6.0
├── optimist@0.6.1
├── promise@7.0.4
├── q@1.4.1
├── rsvp@3.1.0
├── streamline@1.0.7
├── text-table@0.2.0
├── vow@0.4.11
└── when@3.7.4

1. DoxBee sequential

This is Gorki Kosev's benchmark used in the article Analysis of generators and other async patterns in node. The benchmark emulates a situation where N=10000 requests are being made concurrently to execute some mixed async/sync action with fast I/O response times.

This is a throughput benchmark.

Every implementation runs in a freshly created isolated process which is warmed up to the benchmark code before timing it. The memory column represents the highest snapshotted RSS memory (as reported by process.memoryUsage().rss) during processing.

Command: ./bench doxbee (needs cloned repository)

The implementations for this benchmark are found in benchmark/doxbee-sequential directory.

results for 10000 parallel executions, 1 ms per I/O op

file                                       time(ms)  memory(MB)
callbacks-baseline.js                           160       44.53
callbacks-suguru03-neo-async-waterfall.js       227       47.89
promises-bluebird-generator.js                  247       37.76
streamline-callbacks.js                         302       45.64
promises-bluebird.js                            322       31.92
promises-cujojs-when.js                         357       60.88
promises-tildeio-rsvp.js                        419       64.88
promises-lvivski-davy.js                        543      109.81
callbacks-caolan-async-waterfall.js             557      102.08
promises-then-promise.js                        609      124.34
promises-dfilatov-vow.js                        632      138.27
streamline-generators.js                        647       73.85
promises-calvinmetcalf-lie.js                   661      130.81
generators-tj-co.js                             789      137.84
promises-ecmascript6-native.js                  847      182.71
promises-obvious-kew.js                        1240      254.99
promises-medikoo-deferred.js                   2053      201.29
observables-Reactive-Extensions-RxJS.js        2430      279.24
observables-pozadi-kefir.js                    2559      159.62
observables-baconjs-bacon.js.js               18482      883.22
promises-kriskowal-q.js                       23081      876.11
observables-caolan-highland.js                28138      517.57

Platform info:
Linux 3.13.0-32-generic x64
Node.JS 4.2.1
V8 4.5.103.35
Intel(R) Core(TM) i7-4900MQ CPU @ 2.80GHz × 8

2. Parallel

This made-up scenario runs 25 shimmed queries in parallel per each request (N=10000) with fast I/O response times.

This is a throughput benchmark.

Every implementation runs in a freshly created isolated process which is warmed up to the benchmark code before timing it. The memory column represents the highest snapshotted RSS memory (as reported by process.memoryUsage().rss) during processing.

Command: ./bench parallel (needs cloned repository)

The implementations for this benchmark are found in benchmark/madeup-parallel directory.

results for 10000 parallel executions, 1 ms per I/O op

file                                      time(ms)  memory(MB)
callbacks-baseline.js                          290       49.25
promises-bluebird.js                           382       72.45
promises-bluebird-generator.js                 407       76.25
callbacks-suguru03-neo-async-parallel.js       472       97.05
promises-tildeio-rsvp.js                       597      182.07
promises-cujojs-when.js                        610      142.19
callbacks-caolan-async-parallel.js             804      157.11
promises-lvivski-davy.js                      1229      262.84
promises-calvinmetcalf-lie.js                 1301      338.68
promises-then-promise.js                      1585      367.77
streamline-callbacks.js                       1800      315.59
promises-ecmascript6-native.js                1816      481.08
promises-dfilatov-vow.js                      1980      489.30
promises-medikoo-deferred.js                  4181      522.04
promises-obvious-kew.js                       5473     1075.70
streamline-generators.js                      7980      840.97

Platform info:
Linux 3.13.0-32-generic x64
Node.JS 4.2.1
V8 4.5.103.35
Intel(R) Core(TM) i7-4900MQ CPU @ 2.80GHz × 8

3. Latency benchmarks

For reasonably fast promise implementations latency is going to be fully determined by the scheduler being used and is therefore not interesting to benchmark. JSPerfs that benchmark promises tend to benchmark latency.