[pull] master from Melon-Tropics:master

contrib/tracing/README.md

@@ -286,3 +286,53 @@ Spent   a05880b8c77971ed0b9f73062c7c4cdb0ff3856ab14cbf8bc481ed571cd34b83:1
 Added   eb689865f7d957938978d6207918748f74e6aa074f47874724327089445b0960:0            5589696005 2094513 No
 Added   eb689865f7d957938978d6207918748f74e6aa074f47874724327089445b0960:1               1565556 2094513 No
 ```
+
+### mempool_monitor.py
+
+A BCC Python script producing mempool statistics and an event log. Based on the
+`mempool:added`, `mempool:removed`, `mempool:replaced`, and `mempool:rejected`
+tracepoints.
+
+Statistics include incidence and rate for each event type since the script was
+started (`total`) as well as during the last minute (`1 min`) and ten minutes
+(`10 min`). The event log shows mempool events in real time, each entry
+comprising a timestamp along with all event data available via the event's
+tracepoint.
+
+```console
+$ python3 contrib/tracing/mempool_monitor.py ./src/bitcoind
+```
+
+```
+ Mempool Monitor
+ Press CTRL-C to stop.
+
+ ┌─Event count───────────────────────┐  ┌─Event rate──────────────────────────┐
+ │ Event       total   1 min  10 min │  │ Event       total    1 min   10 min │
+ │ added      1425tx   201tx  1425tx │  │ added     4.7tx/s  3.4tx/s  4.7tx/s │
+ │ removed      35tx     4tx    35tx │  │ removed   0.1tx/s  0.1tx/s  0.1tx/s │
+ │ replaced     35tx     4tx    35tx │  │ replaced  0.1tx/s  0.1tx/s  0.1tx/s │
+ │ rejected      0tx     0tx     0tx │  │ rejected  0.0tx/s  0.0tx/s  0.0tx/s │
+ └───────────────────────────────────┘  └─────────────────────────────────────┘
+
+ ┌─Event log────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
+ │ 13:10:30Z added f9064ca5bfc87cdd191faa42bf697217cd920b2b94838c1f1192e4f06c4fd217 with feerate 8.92 sat/vB (981 sat, 110 vbytes)                                              │
+ │ 13:10:30Z added 53ffa3afbe57b1bfe423e1755ca2b52c5b6cb4aa91b8b7ee9cb694953f47f234 with feerate 5.00 sat/vB (550 sat, 110 vbytes)                                              │
+ │ 13:10:30Z added 4177df5e19465eb5e53c3f8b6830a293f57474921bc6c2ae89375e0986e1f0f9 with feerate 2.98 sat/vB (429 sat, 144 vbytes)                                              │
+ │ 13:10:30Z added 931a10d83f0a268768da75dc4b9e199f2f055f12979ae5491cc304ee10f890ea with feerate 3.55 sat/vB (500 sat, 141 vbytes)                                              │
+ │ 13:10:30Z added 4cf32b295723cc4ab73f2a2e51d4bb276c0042760a4c00a3eb9595b8ebb24721 with feerate 89.21 sat/vB (12668 sat, 142 vbytes)                                           │
+ │ 13:10:31Z replaced d1eecf9d662121322f4f31f0c2267a752d14bb3956e6016ba96e87f47890e1db with feerate 27.12 sat/vB received 23.3 seconds ago (7213 sat, 266 vbytes) with c412db908│
+ │ 9b7ed53f3e5e36d2819dd291278b59ccaabaeb17fd37c3d87fdcd57 with feerate 28.12 sat/vB (8351 sat, 297 vbytes)                                                                     │
+ │ 13:10:31Z added c412db9089b7ed53f3e5e36d2819dd291278b59ccaabaeb17fd37c3d87fdcd57 with feerate 28.12 sat/vB (8351 sat, 297 vbytes)                                            │
+ │ 13:10:31Z added b8388a5bdc421b11460bdf477d5a85a1a39c2784e7dd7bffabe688740424ea57 with feerate 25.21 sat/vB (3554 sat, 141 vbytes)                                            │
+ │ 13:10:31Z added 4ddb88bc90a122cd9eae8a664e73bdf5bebe75f3ef901241b4a251245854a98e with feerate 24.15 sat/vB (5072 sat, 210 vbytes)                                            │
+ │ 13:10:31Z added 19101e4161bca5271ad5d03e7747f2faec7793b274dc2f3c4cf516b7cef1aac3 with feerate 7.06 sat/vB (1080 sat, 153 vbytes)                                             │
+ │ 13:10:31Z removed d1eecf9d662121322f4f31f0c2267a752d14bb3956e6016ba96e87f47890e1db with feerate 27.12 sat/vB (7213 sat, 266 vbytes): replaced                                │
+ │ 13:10:31Z added 6c511c60d9b95b9eff81df6ecba5c86780f513fe62ce3ad6be2c5340d957025a with feerate 4.00 sat/vB (440 sat, 110 vbytes)                                              │
+ │ 13:10:31Z added 44d66f7f004bd52c46be4dff3067cab700e51c7866a84282bd8aab560a5bfb79 with feerate 3.15 sat/vB (448 sat, 142 vbytes)                                              │
+ │ 13:10:31Z added b17b7c9ec5acfbbf12f0eeef8e29826fad3105bb95eef7a47d2f1f22b4784643 with feerate 4.10 sat/vB (1348 sat, 329 vbytes)                                             │
+ │ 13:10:31Z added b7a4ad93554e57454e8a8049bfc0bd803fa962bd3f0a08926aa72e7cb23e2276 with feerate 1.01 sat/vB (205 sat, 202 vbytes)                                              │
+ │ 13:10:32Z added c78e87be86c828137a6e7e00a177c03b52202ce4c39029b99904c2a094b9da87 with feerate 11.00 sat/vB (1562 sat, 142 vbytes)                                            │
+ │                                                                                                                                                                              │
+ └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
+```