Adr/network reliability

[pgrange]

This ADR describes assumptions and responsibilities of the networking layer to ensure reliability. See #188

---

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

[github-actions]

Transactions 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	2023-09-26 09:51:50.611970994 UTC
Max. memory units	14000000
Max. CPU units	10000000000
Max. tx size (kB)	16384

Script summary

Name	Hash	Size (Bytes)
νInitial	eaf589de11c6c805af24b759e7794d62661d3db4ade79594892ebaec	4106
νCommit	8dcc1fb34d1ba168dfb0b82e7d1a31956a2db5856f268146b0fd7f2a	2051
νHead	e35bdf32cd3806596150c1cbab6ab5456bd957b36019ed2746bf481d	8797
μHead	386ad19467be96131379dacf57a9351a762da2dee3486a855f0409c9*	4151

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

Cost of Init Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	4745	11.70	4.61	0.49
2	4949	14.15	5.55	0.52
3	5155	16.36	6.38	0.56
5	5569	21.29	8.26	0.63
10	6590	33.42	12.89	0.80
37	12127	96.56	36.92	1.73

Cost of Commit Transaction

This is using ada-only outputs for better comparability.

UTxO	Tx size	% max Mem	% max CPU	Min fee ₳
1	598	12.64	4.97	0.31
2	787	16.26	6.61	0.36
3	975	20.11	8.33	0.42
5	1350	28.23	11.94	0.52
10	2287	50.99	21.84	0.82
18	3788	94.67	40.33	1.37

Cost of CollectCom Transaction

Parties	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
1	57	814	23.84	9.50	0.45
2	113	1134	36.27	14.59	0.60
3	171	1456	54.65	22.03	0.81
4	226	1775	69.26	28.19	0.99
5	282	2094	93.64	38.08	1.27

Cost of Close Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	693	19.23	8.84	0.40
2	899	21.00	10.42	0.43
3	1136	22.83	12.04	0.47
5	1576	26.20	15.17	0.54
10	2572	34.60	22.66	0.71
50	10810	98.40	81.92	2.01

Cost of Contest Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	713	22.67	10.13	0.44
2	962	24.63	11.81	0.48
3	1140	26.10	13.10	0.51
5	1608	30.38	16.72	0.59
10	2569	39.11	24.17	0.75
42	9144	97.05	74.19	1.87

Cost of Abort Transaction

Some variation because of random mixture of still initial and already committed outputs.

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	5019	21.36	9.22	0.61
2	5484	35.95	15.71	0.80
3	5906	53.95	23.69	1.02
4	6316	75.91	33.36	1.28
5	6753	99.90	44.00	1.57

Cost of FanOut Transaction

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 ₳
5	0	0	4767	8.95	3.77	0.46
5	1	57	4803	10.08	4.50	0.48
5	5	284	4951	15.44	7.74	0.55
5	10	569	5122	21.61	11.58	0.63
5	20	1137	5484	34.94	19.66	0.82
5	30	1706	5845	47.77	27.55	0.99
5	40	2274	6199	60.68	35.46	1.17
5	50	2847	6567	73.95	43.53	1.35
5	70	3983	7287	99.83	59.40	1.71

End-To-End Benchmark Results

This page is intended to collect the latest end-to-end benchmarks results produced by Hydra's Continuous Integration system from the latest master code.

Please take those results with a grain of salt as they are currently produced from very limited cloud VMs and not controlled hardware. Instead of focusing on the absolute results, the emphasis should be on relative results, eg. how the timings for a scenario evolve as the code changes.

Generated at 2023-09-26 09:43:12.128619448 UTC

3-nodes Scenario

A rather typical setup, with 3 nodes forming a Hydra head.

Number of nodes	3
Number of txs	900
Avg. Confirmation Time (ms)	119.291241551
P99	312.36531404999994ms
P95	240.54164164999995ms
P50	106.2657595ms
Number of Invalid txs	0

Baseline Scenario

This scenario represents a minimal case and as such is a good baseline against which to assess the overhead introduced by more complex setups. There is a single hydra-node d with a single client submitting single input and single output transactions with a constant UTxO set of 1.

Number of nodes	1
Number of txs	300
Avg. Confirmation Time (ms)	5.637089610
P99	18.31750805999999ms
P95	12.513279ms
P50	4.2738285000000005ms
Number of Invalid txs	0

[github-actions]

Test Results

359 tests   354 ✔️  15m 49s ⏱️
122 suites      5 💤
    6 files        0 ❌

Results for commit 4f9a84a.

♻️ This comment has been updated with latest results.

[v0d1ch]

LGTM

[ch1bo]

I like the context section as it gives a good introduction. In my opinion, to approve and merge this, only a few more clarifications are needed (see below). None of them are show-stoppers though.