Wip: ADR 35

[v0d1ch]

• https://claude.ai/code/artifact/6295f17b-f8c3-494c-8120-054812fd7742

• https://claude.ai/code/artifact/998138d6-df29-497b-aef5-7f28addcbd60

---

• 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

No cost or size differences found

[github-actions]

End-to-end benchmark differences

Comparing this PR (new) against master (old). Numbers come from cloud VMs, so changes under 5% are shown as ≈ and are likely run-to-run noise rather than a real regression or improvement. 🟢 = improvement, 🔴 = regression; uncolored rows are neutral measures reported for context.

Sustained load (3 nodes, 3x5000 txs)

Metric	master	PR	Δ
End-to-end TPS (tx/s)	495.57	494.55	≈ -1.02 (-0.2%)
Sustained TPS (tx/s)	1,035.18	897.35	🔴 -137.83 (-13.3%)
Backlog drain time (s)	29.60	29.50	≈ -0.10 (-0.3%)
Snapshots per second (/s)	0.56	0.53	-0.03 (-5.4%)
Avg txs per snapshot	882.40	937.50	+55.10 (+6.2%)
Avg. Confirmation Time (s)	24.571	24.243	≈ -0.328 (-1.3%)
P50 confirmation (s)	26.072	25.466	≈ -0.606 (-2.3%)
P95 confirmation (s)	29.679	29.517	≈ -0.163 (-0.5%)
P99 confirmation (s)	29.910	29.681	≈ -0.229 (-0.8%)
Tx validation time p50 (s)	8.606	8.488	≈ -0.118 (-1.4%)
Peak node RSS (MB)	413.90	451.10	+37.20 (+9.0%)
Invalid txs	0.00	0.00	≈ +0.00 (n/a%)

Plateau 1000 UTxO (1 node, 4000 txs)

Metric	master	PR	Δ
End-to-end TPS (tx/s)	227.71	231.12	≈ +3.41 (+1.5%)
Backlog drain time (s)	17.50	17.20	≈ -0.30 (-1.7%)
Snapshots per second (/s)	0.46	0.40	-0.06 (-13.0%)
Avg txs per snapshot	500.00	571.40	+71.40 (+14.3%)
Avg. Confirmation Time (s)	10.958	10.936	≈ -0.021 (-0.2%)
P50 confirmation (s)	13.388	11.773	🟢 -1.614 (-12.1%)
P95 confirmation (s)	16.951	17.193	≈ +0.242 (+1.4%)
P99 confirmation (s)	17.459	17.202	≈ -0.258 (-1.5%)
Tx validation time p50 (s)	5.358	4.734	🟢 -0.624 (-11.6%)
Peak node RSS (MB)	393.30	388.10	≈ -5.20 (-1.3%)
Invalid txs	0.00	0.00	≈ +0.00 (n/a%)

Round-trip latency (3 nodes, closed-loop, 3x250 txs)

Metric	master	PR	Δ
End-to-end TPS (tx/s)	94.25	105.24	🟢 +10.99 (+11.7%)
Sustained TPS (tx/s)	94.52	105.32	🟢 +10.80 (+11.4%)
Backlog drain time (s)	0.00	0.00	≈ +0.00 (n/a%)
Snapshots per second (/s)	63.71	71.00	+7.29 (+11.4%)
Avg txs per snapshot	1.50	1.50	≈ +0.00 (+0.0%)
Avg. Confirmation Time (s)	0.032	0.028	🟢 -0.003 (-10.2%)
P50 confirmation (s)	0.031	0.028	🟢 -0.003 (-10.7%)
P95 confirmation (s)	0.041	0.036	🟢 -0.004 (-10.6%)
P99 confirmation (s)	0.047	0.042	🟢 -0.005 (-10.4%)
Tx validation time p50 (s)	0.009	0.007	🟢 -0.001 (-12.9%)
Peak node RSS (MB)	149.10	149.00	≈ -0.10 (-0.1%)
Invalid txs	0.00	0.00	≈ +0.00 (n/a%)

[github-actions]

Transaction costs

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	2026-08-25 10:51:58.796124106 UTC
Max. memory units	14000000
Max. CPU units	10000000000
Max. tx size (kB)	16384

Script summary

Name	Hash	Size (Bytes)
νHead	1d511733200df551c8cd8cddb3160ed39087af815638be37a1b80ffd	12962
μHead	603f261bc5a01f5f4ed988cc07a40a130b94e6820c28e9affde82d9e*	4971
νDeposit	eafae2c32f99ab347c7bb15961e0e84c74305f9088c1a7b8abf88e7f	2117
νCRS	09db7ee6cf7a4b358dd5c8a2f19d2c048336ffc5a01ef35a47ca7072	2736

• 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	5473	9.65	3.18	0.50
2	5572	9.80	3.21	0.50
3	5667	10.20	3.34	0.51
5	5858	11.68	3.83	0.54
10	6340	14.18	4.63	0.58
50	10182	35.19	11.18	0.97
100	14983	62.10	19.59	1.46
114	16327	69.98	22.07	1.60

Cost of Increment Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	2827	21.40	7.67	0.70
2	2958	22.37	8.64	0.72
3	3085	23.54	9.68	0.75
5	3348	25.27	11.56	0.78
10	4002	29.67	16.28	0.88
50	9244	72.59	56.38	1.75
75	12524	98.53	81.15	2.28

Cost of Decrement Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	642	18.52	6.70	0.58
2	772	19.46	7.66	0.60
3	904	20.41	8.63	0.62
5	1168	22.37	10.59	0.66
10	1822	27.11	15.43	0.76
50	7063	67.57	54.75	1.60
75	10342	93.30	79.44	2.13

Close transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	669	17.76	11.66	0.61
2	800	18.71	12.63	0.63
3	928	19.71	13.62	0.65
5	1195	21.61	15.56	0.69
10	1850	26.52	20.46	0.79
50	7090	67.84	60.11	1.64
75	10361	93.23	84.77	2.17

Contest transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	701	21.49	14.90	0.66
2	832	22.65	15.94	0.68
3	964	23.80	16.97	0.71
5	1226	26.09	19.03	0.75
10	1876	31.71	24.14	0.86
50	7122	79.56	65.74	1.78
66	9217	98.71	82.38	2.15

FanOut transaction costs

Involves spending head output and burning head tokens. Uses ada-only UTXO for better comparability.
Rows first grow the UTxO set at a fixed 10 parties, then show the largest set that still fits per number of parties (burning more participation tokens leaves less room for outputs).

Parties	UTxO	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
10	0	0	5644	23.70	43.00	1.14
10	1	57	5678	26.05	45.51	1.18
10	5	285	5814	36.28	55.83	1.34
10	10	568	5983	50.26	69.12	1.56
10	20	1139	6324	82.76	97.10	2.04
1	20	1134	6039	76.54	95.13	1.96
5	20	1139	6168	79.31	96.01	2.00
10	20	1139	6323	82.76	97.10	2.04
20	20	1138	6633	90.08	99.38	2.13
50	15	854	7395	95.05	92.01	2.15

PartialFanOut transaction costs

Largest chunk of ada-only outputs that can be distributed in one partial fanout step, computed dynamically. The last row is the maximum total UTxO count where at least one output can still be distributed.

Total UTxO	Distributed	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
11	10	570	987	35.29	66.46	1.20
25	23	1311	1430	68.58	99.53	1.73
30	23	1310	1429	68.58	99.53	1.73
40	23	1308	1427	68.58	99.53	1.73
50	23	1311	1430	68.58	99.53	1.73
100	23	1309	1424	68.58	99.53	1.73
150	23	1308	1427	68.58	99.53	1.73
200	23	1308	1427	68.58	99.53	1.73
200	23	1310	1429	68.58	99.53	1.73

PartialFanOut transaction costs (with native tokens)

Largest chunk of native-token outputs that can be distributed in one partial fanout step, computed dynamically. The last row is the maximum total UTxO count where at least one output can still be distributed.

Total UTxO	Distributed	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
11	10	1140	1631	42.27	68.98	1.30
25	21	2331	2588	76.71	99.30	1.84
30	21	2331	2588	76.71	99.30	1.84
40	21	2016	2258	76.71	99.20	1.83
50	21	2016	2259	76.71	99.20	1.83
100	21	2520	2783	76.71	99.35	1.85
150	21	2079	2325	76.69	99.20	1.83
200	21	1995	2237	76.71	99.20	1.82
200	21	2394	2655	76.69	99.30	1.84

FinalPartialFanOut transaction costs (with native tokens)

Terminal partial fanout step (FanoutProgress → Final) with outputs carrying a native token. Burns all head tokens and proves accumulator exhaustion via BLS proof.

Distributed	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
1	114	5533	22.51	44.44	1.14
5	555	5891	36.06	55.96	1.34
10	1110	6341	54.18	70.75	1.62
10	1150	6381	54.18	70.75	1.62

End-to-end benchmark results

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 2026-08-25 10:53:25.44755878 UTC

Baseline Scenario

Number of nodes	1
Number of txs	300
Load mode	open-loop
Avg. Confirmation Time (ms)	184.4
P99	187.6ms
P95	187.2ms
P50	184.7ms
Tx validation time p50 (ms)	128.9
End-to-end TPS	1595.93 tx/s
Backlog drain time (s)	0.2
Snapshots observed	2
Snapshots per second	10.64 /s
Avg txs per snapshot	150.0
Peak node RSS (MB)	143.5
Number of Invalid txs	0
Fanout outputs	2

Three local nodes

Number of nodes	3
Number of txs	900
Load mode	open-loop
Avg. Confirmation Time (ms)	951.1
P99	985.3ms
P95	984.5ms
P50	947.6ms
Tx validation time p50 (ms)	494.0
End-to-end TPS	911.92 tx/s
Backlog drain time (s)	0.9
Snapshots observed	2
Snapshots per second	2.03 /s
Avg txs per snapshot	450.0
Peak node RSS (MB)	145.9
Number of Invalid txs	0
Fanout outputs	4

Scenario benchmark results

Scenario benchmark results

This page collects results from the scenario matrix: every combination of cluster size, UTxO shape, and incremental-ops mode is exercised by CI from the latest master code and reported below.

Numbers are approximate. They come from cloud VMs rather than controlled hardware, so the useful signal is the relative change between cells and between commits, not the absolute throughput.

Generated at 2026-08-25 11:06:25.342455452 UTC

Summary across cells

TPS columns are rates (transactions per second); Wall clock (s) is the measured elapsed time from the first tx submission to the last confirmation. Times are rounded to one decimal.

Scenario	Txs	Wall clock (s)	End-to-end TPS (tx/s)	Sustained TPS (tx/s)	Avg conf (ms)	P95 conf (ms)
Nodes=1, Constant, fire and forget	30	0.0	1158.38	n/a	25.1	25.6
Nodes=1, Constant, wait for tx valid	30	0.1	204.09	203.13	4.8	6.3
Nodes=1, Growing, fire and forget	30	0.0	1025.49	n/a	28.4	29.0
Nodes=1, Growing, wait for tx valid	30	0.2	173.89	174.20	5.7	6.7
Nodes=1, Mixed, fire and forget	30	0.0	981.02	n/a	29.8	30.3
Nodes=1, Mixed, wait for tx valid	30	0.2	180.46	180.21	5.5	6.9
Nodes=2, Constant, fire and forget	60	0.1	1124.71	n/a	51.6	52.2
Nodes=2, Constant, wait for tx valid	60	0.4	136.77	133.15	14.4	19.0
Nodes=2, Growing, fire and forget	60	0.1	824.12	n/a	71.0	71.9
Nodes=2, Growing, wait for tx valid	60	0.6	92.92	92.81	21.2	26.7
Nodes=2, Mixed, fire and forget	60	0.1	893.30	n/a	64.6	66.0
Nodes=2, Mixed, wait for tx valid	60	0.6	95.15	90.50	20.8	29.2
Nodes=3, Constant, fire and forget	90	0.1	782.45	n/a	111.7	114.0
Nodes=3, Constant, wait for tx valid	90	0.9	99.61	99.05	29.9	39.3
Nodes=3, Growing, fire and forget	90	0.2	562.28	n/a	155.9	158.1
Nodes=3, Growing, wait for tx valid	90	1.1	78.39	79.35	37.5	46.5
Nodes=3, Mixed, fire and forget	90	0.1	613.76	n/a	143.9	146.3
Nodes=3, Mixed, wait for tx valid	90	1.0	86.95	83.39	34.2	43.6

Nodes=1, Constant, fire and forget

Number of nodes	1
Number of txs	30
Load mode	open-loop
Avg. Confirmation Time (ms)	25.1
P99	25.7ms
P95	25.6ms
P50	25.2ms
Tx validation time p50 (ms)	10.0
End-to-end TPS	1158.38 tx/s
Backlog drain time (s)	0.0
Snapshots observed	2
Snapshots per second	77.23 /s
Avg txs per snapshot	15.0
Peak node RSS (MB)	143.0
Number of Invalid txs	0
Fanout outputs	2

Nodes=1, Constant, wait for tx valid

Number of nodes	1
Number of txs	30
Load mode	closed-loop
Avg. Confirmation Time (ms)	4.8
P99	7.8ms
P95	6.3ms
P50	4.7ms
Tx validation time p50 (ms)	1.7
End-to-end TPS	204.09 tx/s
Sustained TPS	203.13 tx/s
Backlog drain time (s)	0.0
Snapshots observed	30
Snapshots per second	204.09 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	143.9
Number of Invalid txs	0
Fanout outputs	2

Nodes=1, Growing, fire and forget

Number of nodes	1
Number of txs	30
Load mode	open-loop
Avg. Confirmation Time (ms)	28.4
P99	29.0ms
P95	29.0ms
P50	28.6ms
Tx validation time p50 (ms)	10.9
End-to-end TPS	1025.49 tx/s
Backlog drain time (s)	0.0
Snapshots observed	2
Snapshots per second	68.37 /s
Avg txs per snapshot	15.0
Peak node RSS (MB)	143.3
Number of Invalid txs	0
Fanout outputs	31

Nodes=1, Growing, wait for tx valid

Number of nodes	1
Number of txs	30
Load mode	closed-loop
Avg. Confirmation Time (ms)	5.7
P99	6.7ms
P95	6.7ms
P50	5.7ms
Tx validation time p50 (ms)	1.6
End-to-end TPS	173.89 tx/s
Sustained TPS	174.20 tx/s
Backlog drain time (s)	0.0
Snapshots observed	30
Snapshots per second	173.89 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	143.4
Number of Invalid txs	0
Fanout outputs	31

Nodes=1, Mixed, fire and forget

Each client first grows its UTxO set (1-in to 2-out) for half of its tx budget, then contracts it back (2-in to 1-out) for the remainder.

Number of nodes	1
Number of txs	30
Load mode	open-loop
Avg. Confirmation Time (ms)	29.8
P99	30.4ms
P95	30.3ms
P50	29.9ms
Tx validation time p50 (ms)	18.8
End-to-end TPS	981.02 tx/s
Backlog drain time (s)	0.0
Snapshots observed	2
Snapshots per second	65.40 /s
Avg txs per snapshot	15.0
Peak node RSS (MB)	143.1
Number of Invalid txs	0
Fanout outputs	2

Nodes=1, Mixed, wait for tx valid

Each client first grows its UTxO set (1-in to 2-out) for half of its tx budget, then contracts it back (2-in to 1-out) for the remainder.

Number of nodes	1
Number of txs	30
Load mode	closed-loop
Avg. Confirmation Time (ms)	5.5
P99	7.8ms
P95	6.9ms
P50	5.3ms
Tx validation time p50 (ms)	1.7
End-to-end TPS	180.46 tx/s
Sustained TPS	180.21 tx/s
Backlog drain time (s)	0.0
Snapshots observed	30
Snapshots per second	180.46 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	143.0
Number of Invalid txs	0
Fanout outputs	2

Nodes=2, Constant, fire and forget

Number of nodes	2
Number of txs	60
Load mode	open-loop
Avg. Confirmation Time (ms)	51.6
P99	52.7ms
P95	52.2ms
P50	51.9ms
Tx validation time p50 (ms)	25.6
End-to-end TPS	1124.71 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	37.49 /s
Avg txs per snapshot	30.0
Peak node RSS (MB)	144.7
Number of Invalid txs	0
Fanout outputs	3

Nodes=2, Constant, wait for tx valid

Number of nodes	2
Number of txs	60
Load mode	closed-loop
Avg. Confirmation Time (ms)	14.4
P99	21.5ms
P95	19.0ms
P50	13.9ms
Tx validation time p50 (ms)	4.2
End-to-end TPS	136.77 tx/s
Sustained TPS	133.15 tx/s
Backlog drain time (s)	0.0
Snapshots observed	60
Snapshots per second	136.77 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	144.9
Number of Invalid txs	0
Fanout outputs	3

Nodes=2, Growing, fire and forget

Number of nodes	2
Number of txs	60
Load mode	open-loop
Avg. Confirmation Time (ms)	71.0
P99	72.3ms
P95	71.9ms
P50	71.3ms
Tx validation time p50 (ms)	29.3
End-to-end TPS	824.12 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	27.47 /s
Avg txs per snapshot	30.0
Peak node RSS (MB)	144.0
Number of Invalid txs	0
Fanout outputs	62

Nodes=2, Growing, wait for tx valid

Number of nodes	2
Number of txs	60
Load mode	closed-loop
Avg. Confirmation Time (ms)	21.2
P99	28.0ms
P95	26.7ms
P50	20.9ms
Tx validation time p50 (ms)	6.3
End-to-end TPS	92.92 tx/s
Sustained TPS	92.81 tx/s
Backlog drain time (s)	0.0
Snapshots observed	60
Snapshots per second	92.92 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	145.6
Number of Invalid txs	0
Fanout outputs	62

Nodes=2, Mixed, fire and forget

Each client first grows its UTxO set (1-in to 2-out) for half of its tx budget, then contracts it back (2-in to 1-out) for the remainder.

Number of nodes	2
Number of txs	60
Load mode	open-loop
Avg. Confirmation Time (ms)	64.6
P99	66.5ms
P95	66.0ms
P50	65.3ms
Tx validation time p50 (ms)	23.2
End-to-end TPS	893.30 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	29.78 /s
Avg txs per snapshot	30.0
Peak node RSS (MB)	144.9
Number of Invalid txs	0
Fanout outputs	3

Nodes=2, Mixed, wait for tx valid

Each client first grows its UTxO set (1-in to 2-out) for half of its tx budget, then contracts it back (2-in to 1-out) for the remainder.

Number of nodes	2
Number of txs	60
Load mode	closed-loop
Avg. Confirmation Time (ms)	20.8
P99	29.5ms
P95	29.2ms
P50	20.3ms
Tx validation time p50 (ms)	5.9
End-to-end TPS	95.15 tx/s
Sustained TPS	90.50 tx/s
Backlog drain time (s)	0.0
Snapshots observed	60
Snapshots per second	95.15 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	146.2
Number of Invalid txs	0
Fanout outputs	3

Nodes=3, Constant, fire and forget

Number of nodes	3
Number of txs	90
Load mode	open-loop
Avg. Confirmation Time (ms)	111.7
P99	114.1ms
P95	114.0ms
P50	112.6ms
Tx validation time p50 (ms)	58.2
End-to-end TPS	782.45 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	17.39 /s
Avg txs per snapshot	45.0
Peak node RSS (MB)	144.8
Number of Invalid txs	0
Fanout outputs	4

Nodes=3, Constant, wait for tx valid

Number of nodes	3
Number of txs	90
Load mode	closed-loop
Avg. Confirmation Time (ms)	29.9
P99	41.8ms
P95	39.3ms
P50	29.8ms
Tx validation time p50 (ms)	8.5
End-to-end TPS	99.61 tx/s
Sustained TPS	99.05 tx/s
Backlog drain time (s)	0.0
Snapshots observed	61
Snapshots per second	67.52 /s
Avg txs per snapshot	1.5
Peak node RSS (MB)	145.2
Number of Invalid txs	0
Fanout outputs	4

Nodes=3, Growing, fire and forget

Number of nodes	3
Number of txs	90
Load mode	open-loop
Avg. Confirmation Time (ms)	155.9
P99	158.3ms
P95	158.1ms
P50	157.2ms
Tx validation time p50 (ms)	48.6
End-to-end TPS	562.28 tx/s
Backlog drain time (s)	0.2
Snapshots observed	2
Snapshots per second	12.50 /s
Avg txs per snapshot	45.0
Peak node RSS (MB)	145.4
Number of Invalid txs	0
Fanout outputs	0

Nodes=3, Growing, wait for tx valid

Number of nodes	3
Number of txs	90
Load mode	closed-loop
Avg. Confirmation Time (ms)	37.5
P99	55.9ms
P95	46.5ms
P50	37.5ms
Tx validation time p50 (ms)	11.0
End-to-end TPS	78.39 tx/s
Sustained TPS	79.35 tx/s
Backlog drain time (s)	0.0
Snapshots observed	61
Snapshots per second	53.13 /s
Avg txs per snapshot	1.5
Peak node RSS (MB)	145.9
Number of Invalid txs	0
Fanout outputs	0

Nodes=3, Mixed, fire and forget

Each client first grows its UTxO set (1-in to 2-out) for half of its tx budget, then contracts it back (2-in to 1-out) for the remainder.

Number of nodes	3
Number of txs	90
Load mode	open-loop
Avg. Confirmation Time (ms)	143.9
P99	146.4ms
P95	146.3ms
P50	144.6ms
Tx validation time p50 (ms)	51.3
End-to-end TPS	613.76 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	13.64 /s
Avg txs per snapshot	45.0
Peak node RSS (MB)	145.1
Number of Invalid txs	0
Fanout outputs	4

Nodes=3, Mixed, wait for tx valid

Each client first grows its UTxO set (1-in to 2-out) for half of its tx budget, then contracts it back (2-in to 1-out) for the remainder.

Number of nodes	3
Number of txs	90
Load mode	closed-loop
Avg. Confirmation Time (ms)	34.2
P99	47.9ms
P95	43.6ms
P50	33.7ms
Tx validation time p50 (ms)	10.6
End-to-end TPS	86.95 tx/s
Sustained TPS	83.39 tx/s
Backlog drain time (s)	0.0
Snapshots observed	61
Snapshots per second	58.93 /s
Avg txs per snapshot	1.5
Peak node RSS (MB)	145.6
Number of Invalid txs	0
Fanout outputs	4