Fix decoding of Hydra keys and ignore problematic head init

[ch1bo]

We were not correctly decoding Hydra verification keys (but crashing via error) because of a missing data constructor.

This also makes the observeInitTx sort out heads that would have such problematic party datums.

An example transaction with problematic data is:
b860a236a7e77577628bf705286d449188831cf90d714934f1cc06369c6e3953 on preprod

---

• CHANGELOG updated or not needed
• Documentation updated or not needed
• Haddocks updated or not needed
• No new TODOs introduced or explained herafter

[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	2025-02-14 20:20:21.482045346 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	10.98	3.42	0.53
2	6295	13.47	4.19	0.57
3	6495	15.68	4.86	0.60
5	6898	20.19	6.25	0.66
10	7901	31.40	9.68	0.82
40	13936	98.39	30.22	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	739	3.38	1.73	0.22
3	918	4.36	2.33	0.24
5	1279	6.41	3.60	0.28
10	2178	12.13	7.25	0.40
54	10061	98.61	68.52	1.88

CollectCom transaction costs

Parties	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
1	57	525	25.64	7.39	0.43
2	114	636	34.95	10.02	0.53
3	170	747	43.25	12.40	0.62
4	225	858	54.85	15.57	0.74
5	281	969	66.84	18.76	0.87
6	340	1081	78.92	22.11	0.99
7	395	1196	84.52	23.81	1.06
8	451	1303	87.14	24.97	1.09

Cost of Increment Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	1789	25.50	8.33	0.50
2	1886	25.97	9.08	0.51
3	2123	29.66	11.03	0.56
5	2471	33.53	13.67	0.63
10	3246	43.98	20.42	0.80
37	7389	97.48	55.82	1.67

Cost of Decrement Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	607	23.95	7.60	0.43
2	789	26.73	9.03	0.47
3	907	27.50	9.89	0.48
5	1134	30.05	11.96	0.53
10	1980	43.69	19.02	0.73
39	6352	98.10	53.38	1.61

Close transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	677	29.15	9.20	0.48
2	774	30.24	10.11	0.50
3	936	32.82	11.65	0.54
5	1276	40.11	15.31	0.64
10	2048	51.09	22.23	0.81
34	5509	95.98	52.59	1.55

Contest transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	667	35.95	11.00	0.55
2	768	37.41	12.00	0.57
3	899	39.54	13.31	0.61
5	1247	45.22	16.53	0.69
10	2021	57.12	23.64	0.87
27	4589	99.04	48.18	1.50

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	5968	28.20	9.30	0.71
2	6128	38.80	12.83	0.83
3	6190	43.45	14.29	0.88
4	6354	53.74	17.73	0.99
5	6540	64.04	21.12	1.11
6	6702	74.59	24.69	1.23
7	6756	82.80	27.30	1.31
8	6904	96.80	32.00	1.47

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	6092	20.05	6.60	0.63
10	1	56	6124	20.87	6.98	0.64
10	10	569	6430	40.96	14.72	0.87
10	30	1709	7113	82.65	30.94	1.35
10	38	2163	7382	99.89	37.62	1.55

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 2025-02-14 20:23:18.662676171 UTC

Baseline Scenario

Number of nodes	1
Number of txs	300
Avg. Confirmation Time (ms)	4.097790956
P99	14.255678ms
P95	4.4649202ms
P50	3.7793514999999998ms
Number of Invalid txs	0

Memory data

Time	Used	Free
2025-02-14 20:21:53.685416644 UTC	925M	2291M
2025-02-14 20:21:58.685412049 UTC	1047M	2145M
2025-02-14 20:22:03.685425229 UTC	1008M	2184M
2025-02-14 20:22:08.685410692 UTC	1008M	2184M
2025-02-14 20:22:13.685421084 UTC	1010M	2182M
2025-02-14 20:22:18.685347114 UTC	1021M	2170M

Three local nodes

Number of nodes	3
Number of txs	900
Avg. Confirmation Time (ms)	22.771286034
P99	113.77056891ms
P95	30.437010299999997ms
P50	20.207447000000002ms
Number of Invalid txs	0

Memory data

Time	Used	Free
2025-02-14 20:22:31.602237297 UTC	950M	2253M
2025-02-14 20:22:36.602306231 UTC	1113M	2089M
2025-02-14 20:22:41.602447195 UTC	1121M	2081M
2025-02-14 20:22:46.60223432 UTC	1123M	2078M
2025-02-14 20:22:51.602424164 UTC	1167M	1966M
2025-02-14 20:22:56.602459133 UTC	1188M	1863M
2025-02-14 20:23:01.602410699 UTC	1204M	1847M
2025-02-14 20:23:06.602509662 UTC	1207M	1843M
2025-02-14 20:23:11.602398006 UTC	1207M	1843M
2025-02-14 20:23:16.602577062 UTC	1213M	1837M

[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	-	-	-	-
2	-	-	-	-
3	-	+0.39	+0.09	-
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)	-	-	-	-	-

[noonio]

Great!