Multi party, networked offline heads

[ch1bo]

This is a change I encountered when rebasing raft-network for #1720 and was useful back in the spike, but would have also been valuable in the hydra-doom use case.

Anyways, this is adding a --offline-head-seed argument to offline mode and fixes the "simulation" opened head to be deterministic across multiple instances, resulting that the nodes can and do talk to each other and consequently sign snapshots.

---

• CHANGELOG updated
• Documentation updated
• Haddocks updated
• No new TODOs introduced

[github-actions]

Transaction cost differences

Script summary

Name	Size (Bytes)
νInitial	-
νCommit	-
νHead	-
μHead	-
νDeposit	-

Init transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	-	-	-	-
2	-	-	-	-
3	-	-	-	-
5	-	-	-	-
10	-	-	-	-
40	-	-	-	-

Commit transaction costs

UTxO	Tx size	% max Mem	% max CPU	Min fee ₳
1	-	-	-	-
2	-	-	-	-
3	-	-	-	-
5	-	-	-	-
10	-	-	-	-
54	-	-	-	-

CollectCom transaction costs

Parties	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
1	-	-	-	-	-
2	-	-	-	-	-
3	-	-	-	-	-
4	-	-	-	-	-
5	-	-	-	-	-
6	-	-	-	-	-
7	-	-	-	-	-
8	-	-	-	-	-

Cost of Increment Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	-	+0.39	+0.09	-
2	-	-	-	-
3	-	-	-	-
5	-	-	-	-
10	-	-	-	-
37	-	-	-	-

Cost of Decrement Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	-	-	-	-
2	-	-	-	-
3	-	-	-	-
5	-	-	-	-
10	-	-	-	-
40	-	-	-	-

Close transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	-	-	-	-
2	-	-	-	-
3	-	-	-	-
5	-	-	-	-
10	-	-	-	-
34	-	-	-	-

Contest transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	-	-	-	-
2	-	-	-	-
3	-	-	-	-
5	-	-	-	-
10	-	-	-	-
27	-	-	-	-

FanOut transaction costs

UTxO, Parties	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
(0, 10)	-	-	-	-	-
(1, 10)	-	-	-	-	-
(5, 10)	-	-	-	-	-
(10, 10)	-	-	-	-	-
(20, 10)	-	-	-	-	-
(37, 10)	-	-	-	-	-

[github-actions]

Transaction costs

Sizes and execution budgets for Hydra protocol transactions. Note that unlisted parameters are currently using arbitrary values and results are not fully deterministic and comparable to previous runs.

Metadata
Generated at	2025-02-17 10:16:38.872512039 UTC
Max. memory units	14000000
Max. CPU units	10000000000
Max. tx size (kB)	16384

Script summary

Name	Hash	Size (Bytes)
νInitial	c8a101a5c8ac4816b0dceb59ce31fc2258e387de828f02961d2f2045	2652
νCommit	61458bc2f297fff3cc5df6ac7ab57cefd87763b0b7bd722146a1035c	685
νHead	0e35115a2c7c13c68ecd8d74e4987c04d4539e337643be20bb3274bd	14756
μHead	57166715eadb8d3135964325c016eea546c21e1c0aae974ca67df9a5*	5541
νDeposit	ae01dade3a9c346d5c93ae3ce339412b90a0b8f83f94ec6baa24e30c	1102

• The minting policy hash is only usable for comparison. As the script is parameterized, the actual script is unique per head.

Init transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	6093	11.32	3.53	0.54
2	6298	13.56	4.22	0.57
3	6493	15.68	4.86	0.60
5	6898	19.98	6.17	0.66
10	7904	31.18	9.61	0.82
40	13936	98.61	30.29	1.78

Commit transaction costs

This uses ada-only outputs for better comparability.

UTxO	Tx size	% max Mem	% max CPU	Min fee ₳
1	561	2.44	1.16	0.20
2	743	3.38	1.73	0.22
3	923	4.36	2.33	0.24
5	1278	6.41	3.60	0.28
10	2176	12.13	7.25	0.40
54	10057	98.61	68.52	1.88

CollectCom transaction costs

Parties	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
1	57	525	26.47	7.60	0.44
2	113	636	34.96	10.01	0.53
3	171	747	45.83	12.98	0.65
4	226	862	50.58	14.52	0.70
5	283	969	64.15	18.22	0.84
6	341	1081	77.09	21.64	0.98
7	395	1192	86.42	24.26	1.08
8	450	1303	89.35	25.35	1.11

Cost of Increment Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	1806	25.42	8.31	0.49
2	1886	26.01	9.09	0.51
3	2064	28.27	10.55	0.55
5	2391	32.58	13.29	0.61
10	3067	41.13	19.25	0.76
39	7429	98.59	57.10	1.69

Cost of Decrement Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	593	23.99	7.61	0.43
2	801	26.54	8.99	0.46
3	824	25.31	9.28	0.46
5	1185	31.64	12.38	0.55
10	1907	41.04	18.30	0.70
38	6072	96.08	52.15	1.57

Close transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	698	29.15	9.21	0.48
2	789	32.89	10.93	0.53
3	1025	33.52	11.98	0.55
5	1296	39.83	15.25	0.64
10	2166	52.10	22.66	0.83
34	5627	96.54	52.96	1.56

Contest transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	688	35.95	11.01	0.55
2	819	38.11	12.31	0.58
3	1014	41.03	13.96	0.63
5	1261	45.29	16.56	0.69
10	2032	57.60	23.77	0.88
27	4551	98.05	47.75	1.49

Abort transaction costs

There is some variation due to the random mixture of initial and already committed outputs.

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	5972	28.23	9.31	0.71
2	6183	38.73	12.81	0.83
3	6255	44.20	14.57	0.89
4	6354	53.55	17.66	0.99
5	6447	66.27	21.81	1.13
6	6505	67.59	22.18	1.14
7	6765	84.70	27.97	1.33
8	6855	85.88	28.31	1.35

FanOut transaction costs

Involves spending head output and burning head tokens. Uses ada-only UTXO for better comparability.

Parties	UTxO	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
10	0	0	6091	18.75	6.15	0.61
10	5	284	6261	31.23	10.90	0.76
10	10	570	6432	40.50	14.57	0.87
10	30	1708	7112	83.04	31.07	1.36
10	37	2105	7347	97.56	36.72	1.53

End-to-end benchmark results

This page is intended to collect the latest end-to-end benchmark results produced by Hydra's continuous integration (CI) system from the latest master code.

Please note that these results are approximate as they are currently produced from limited cloud VMs and not controlled hardware. Rather than focusing on the absolute results, the emphasis should be on relative results, such as how the timings for a scenario evolve as the code changes.

Generated at 2025-02-17 10:19:37.652582387 UTC

Baseline Scenario

Number of nodes	1
Number of txs	300
Avg. Confirmation Time (ms)	4.168704500
P99	10.003814869999959ms
P95	4.86708535ms
P50	3.9635179999999997ms
Number of Invalid txs	0

Memory data

Time	Used	Free
2025-02-17 10:18:14.416211708 UTC	927M	2234M
2025-02-17 10:18:19.416137444 UTC	1000M	2140M
2025-02-17 10:18:24.416049725 UTC	1000M	2140M
2025-02-17 10:18:29.416116955 UTC	1003M	2136M
2025-02-17 10:18:34.416114005 UTC	1014M	2125M
2025-02-17 10:18:39.416025186 UTC	1014M	2124M

Three local nodes

Number of nodes	3
Number of txs	900
Avg. Confirmation Time (ms)	22.726207555
P99	45.01031833999936ms
P95	30.30747325ms
P50	20.872570000000003ms
Number of Invalid txs	0

Memory data

Time	Used	Free
2025-02-17 10:18:51.484123731 UTC	932M	2219M
2025-02-17 10:18:56.484179894 UTC	1094M	2055M
2025-02-17 10:19:01.48427395 UTC	1104M	2045M
2025-02-17 10:19:06.484143667 UTC	1144M	2005M
2025-02-17 10:19:11.484246188 UTC	1168M	1892M
2025-02-17 10:19:16.484241755 UTC	1193M	1806M
2025-02-17 10:19:21.484219385 UTC	1193M	1805M
2025-02-17 10:19:26.484222927 UTC	1209M	1789M
2025-02-17 10:19:31.484245257 UTC	1209M	1788M
2025-02-17 10:19:36.484181723 UTC	1214M	1782M

[noonio]

Seems great; aside from minor clarification around whether or not the head-seed actually must be hexadecimals :)

Seems like it's better if it's just an arbitrary string.