Restarting the node with different parameters

[v0d1ch]

Fix #764

NOTE: This is initial work on this item as I wanted to gather reviews. This PR only checks the contestation period and the parties. If the approach is good I will add more checks to complete our objective.

Why

We want our hydra-node to behave well with respect to the provided arguments. In the presence of existing state it can happen that the arguments are not in line with what we have already in our state. For these cases we want to prevent the hydra-node from operating further until either state is cleared or node arguments match the state.

What

Check node state (if any) against the provided arguments, log and fail if we discover misconfiguration.

• CHANGELOG updated
• Documentation updated
• Added and/or updated haddocks
• 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	2023-03-17 19:47:46.606664228 UTC
Max. memory units	14000000
Max. CPU units	10000000000
Max. tx size (kB)	16384

Script summary

Name	Hash	Size (Bytes)
νInitial	9492414f8f96e8483a0b8ee268fc06a954641cb2cbaa9a8b093c2c9b	4621
νCommit	5d3f107aaa56d06188cf231941cf8163e777236a9cfdc48fd4bbfa23	2422
νHead	82f16b51e2d81c6f4d42dd7398b4713a445464902f63dfd86ffe754e	8954
μHead	4083fa7081a0f4b4092fb02867c9ac594bb0e8bab8110ab242ba5a72*	4458

• 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	5056	13.49	5.31	0.52
2	5257	16.34	6.41	0.56
3	5464	20.21	7.92	0.61
5	5872	24.25	9.42	0.67
10	6897	37.26	14.37	0.86
36	12231	99.27	37.80	1.76

Cost of Commit Transaction

Currently only one UTxO per commit allowed (this is about to change soon)

UTxO	Tx size	% max Mem	% max CPU	Min fee ₳
1	603	15.83	6.22	0.35

Cost of CollectCom Transaction

Parties	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
1	57	816	24.42	9.92	0.45
2	114	1137	40.75	16.66	0.65
3	171	1462	59.33	24.41	0.87
4	227	1784	81.13	33.50	1.13

Cost of Close Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	672	17.74	7.77	0.38
2	805	18.73	8.21	0.40
3	965	20.08	8.96	0.42
5	1307	22.70	10.43	0.47
10	1471	24.26	10.67	0.49
50	8725	85.93	45.27	1.55

Cost of Contest Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	676	21.73	9.11	0.42
2	832	23.88	10.16	0.45
3	1005	25.16	10.88	0.48
5	1337	28.72	12.69	0.53
10	2160	37.37	17.14	0.67
46	8109	99.36	49.05	1.66

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	5171	29.49	12.60	0.71
2	5491	48.17	20.80	0.93
3	5817	70.08	30.47	1.19
4	6138	95.38	41.62	1.49

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	5077	10.59	4.43	0.49
5	1	57	5113	12.12	5.31	0.51
5	5	283	5255	18.22	8.83	0.59
5	10	569	5436	25.85	13.24	0.69
5	20	1140	5797	41.11	22.05	0.90
5	30	1707	6156	56.37	30.86	1.10
5	40	2277	6516	71.64	39.68	1.30
5	50	2849	6879	86.92	48.50	1.50
5	58	3305	7170	99.14	55.56	1.67

[github-actions]

Test Results

307 tests  +12   301 ✔️ +12   24m 49s ⏱️ + 4m 45s
104 suites +  4       6 💤 ±  0 
    6 files   +  1       0 ❌ ±  0 

Results for commit b1b3e15. ± Comparison against base commit 2c34d91.

♻️ This comment has been updated with latest results.

[pgrange]

I understand that, for now, you're not looking for a P.R. per se but for preliminary comments. So here are mine.

Cheers,

[ch1bo]

I think we can reduce the complexity of this also by not being too strict on the level of detail required. IMO it is sufficient to say, that the loaded state is not matching what was configured. Maybe with another message to indicate check state in --persistence-dir against provided command line options

[ch1bo]

Some inconsistencies still, but I can approve even without these changes.