Don't rely on local state when observing decrement and recover txs

[v0d1ch]

• We should not prevent any on-chain information from propagating further since the only source of truth is actually what we observe from L1. This PR removes some parts of the code that made some assumptions using local state of a hydra-node which we can't really trust.

This PR goes together with the one removing related check from the hydra specification #1930

---

• 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 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	-	$${\color{green}-0.39}$$	$${\color{green}-0.09}$$	-
10	-	$${\color{green}-0.39}$$	$${\color{green}-0.09}$$	$${\color{green}-0.01}$$
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	2025-04-10 10:57:25.415506063 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	6091	11.02	3.43	0.53
2	6299	13.74	4.28	0.57
3	6500	15.28	4.73	0.59
5	6895	20.38	6.31	0.66
10	7903	30.97	9.53	0.82
40	13935	98.27	30.17	1.77

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	742	3.38	1.73	0.22
3	923	4.36	2.33	0.24
5	1279	6.41	3.60	0.28
10	2171	12.13	7.25	0.40
54	10078	98.61	68.52	1.88

CollectCom transaction costs

Parties	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
1	57	529	25.64	7.39	0.43
2	113	636	34.89	9.99	0.53
3	170	747	43.26	12.38	0.62
4	228	862	56.51	15.96	0.76
5	284	969	64.76	18.37	0.85
6	340	1081	76.71	21.55	0.97
7	393	1192	80.52	22.90	1.02
8	452	1303	95.28	27.02	1.17

Cost of Increment Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	1787	25.03	8.22	0.49
2	1931	26.64	9.38	0.52
3	2017	27.16	10.15	0.53
5	2478	33.87	13.75	0.63
10	3226	43.83	20.32	0.79
39	7322	95.96	56.29	1.65

Cost of Decrement Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	597	23.71	7.54	0.42
2	815	26.46	8.97	0.46
3	903	28.41	10.16	0.49
5	1127	29.72	11.83	0.53
10	1900	39.76	17.94	0.68
39	6197	98.25	53.40	1.60

Close transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	690	29.15	9.21	0.48
2	782	32.85	10.92	0.53
3	930	34.71	12.16	0.56
5	1444	39.20	15.35	0.64
10	1935	49.48	21.50	0.79
34	5387	99.16	53.18	1.57

Contest transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	628	35.29	10.70	0.54
2	808	38.07	12.30	0.58
3	904	39.54	13.31	0.61
5	1286	45.37	16.59	0.69
10	2030	57.51	23.75	0.88
27	4529	97.41	47.53	1.48

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	6004	28.29	9.33	0.71
2	6050	36.38	11.95	0.80
3	6355	48.94	16.23	0.94
4	6326	56.44	18.58	1.02
5	6526	66.81	22.09	1.14
6	6590	69.26	22.86	1.16
7	6723	82.04	27.02	1.30
8	6891	96.96	32.13	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	19.66	6.46	0.62
10	5	285	6261	30.97	10.82	0.75
10	10	567	6428	41.61	14.95	0.88
10	30	1705	7108	84.03	31.40	1.37
10	37	2102	7344	98.48	37.03	1.54

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 2025-04-10 11:00:09.402675533 UTC

Baseline Scenario

Number of nodes	1
Number of txs	300
Avg. Confirmation Time (ms)	4.392931530
P99	6.7976263599999935ms
P95	5.4041033ms
P50	4.218446999999999ms
Number of Invalid txs	0

Memory data

Time	Used	Free
2025-04-10 10:58:54.409843994 UTC	902M	2920M
2025-04-10 10:58:59.409689716 UTC	996M	2817M
2025-04-10 10:59:04.409665133 UTC	998M	2816M
2025-04-10 10:59:09.409670072 UTC	1008M	2805M
2025-04-10 10:59:14.409665603 UTC	1008M	2805M
2025-04-10 10:59:19.40967258 UTC	1009M	2803M

Three local nodes

Number of nodes	3
Number of txs	900
Avg. Confirmation Time (ms)	27.762516286
P99	41.82732957ms
P95	36.180953049999985ms
P50	26.819914ms
Number of Invalid txs	0

Memory data

Time	Used	Free
2025-04-10 10:59:32.409296971 UTC	906M	2915M
2025-04-10 10:59:37.410954639 UTC	1174M	2643M
2025-04-10 10:59:42.411277751 UTC	1226M	2523M
2025-04-10 10:59:47.409266426 UTC	1247M	2460M
2025-04-10 10:59:52.409280502 UTC	1254M	2452M
2025-04-10 10:59:57.409288569 UTC	1249M	2457M
2025-04-10 11:00:02.40929206 UTC	1251M	2454M
2025-04-10 11:00:07.409275118 UTC	1254M	2450M