Make withTempDir clean up atomically on success

[vrom911]

Resolves #2699

---

• 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)	532.11	469.07	🔴 -63.04 (-11.8%)
Sustained TPS (tx/s)	1,242.46	894.76	🔴 -347.70 (-28.0%)
Backlog drain time (s)	27.60	31.10	🔴 +3.50 (+12.7%)
Snapshots per second (/s)	0.60	0.53	-0.07 (-11.7%)
Avg txs per snapshot	882.40	882.40	≈ +0.00 (+0.0%)
Avg. Confirmation Time (s)	23.369	25.588	🔴 +2.219 (+9.5%)
P50 confirmation (s)	24.830	27.200	🔴 +2.370 (+9.5%)
P95 confirmation (s)	27.696	31.111	🔴 +3.415 (+12.3%)
P99 confirmation (s)	27.812	31.184	🔴 +3.371 (+12.1%)
Tx validation time p50 (s)	11.128	8.127	🟢 -3.001 (-27.0%)
Peak node RSS (MB)	449.60	451.20	≈ +1.60 (+0.4%)
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)	254.43	241.37	🔴 -13.06 (-5.1%)
Backlog drain time (s)	15.70	16.50	🔴 +0.80 (+5.1%)
Snapshots per second (/s)	0.45	0.60	+0.15 (+33.3%)
Avg txs per snapshot	571.40	400.00	-171.40 (-30.0%)
Avg. Confirmation Time (s)	10.748	9.835	🟢 -0.912 (-8.5%)
P50 confirmation (s)	13.020	11.772	🟢 -1.248 (-9.6%)
P95 confirmation (s)	15.652	16.468	🔴 +0.817 (+5.2%)
P99 confirmation (s)	15.653	16.470	🔴 +0.817 (+5.2%)
Tx validation time p50 (s)	4.267	6.349	🔴 +2.082 (+48.8%)
Peak node RSS (MB)	430.70	355.00	-75.70 (-17.6%)
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)	79.05	101.57	🟢 +22.52 (+28.5%)
Sustained TPS (tx/s)	75.20	102.83	🟢 +27.63 (+36.7%)
Backlog drain time (s)	0.00	0.00	≈ +0.00 (n/a%)
Snapshots per second (/s)	53.12	68.25	+15.13 (+28.5%)
Avg txs per snapshot	1.50	1.50	≈ +0.00 (+0.0%)
Avg. Confirmation Time (s)	0.038	0.029	🟢 -0.008 (-22.4%)
P50 confirmation (s)	0.025	0.029	🔴 +0.003 (+14.0%)
P95 confirmation (s)	0.114	0.038	🟢 -0.075 (-66.2%)
P99 confirmation (s)	0.217	0.043	🟢 -0.174 (-80.1%)
Tx validation time p50 (s)	0.006	0.008	🔴 +0.002 (+25.4%)
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

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	2026-08-10 14:17:08.057548694 UTC
Max. memory units	14000000
Max. CPU units	10000000000
Max. tx size (kB)	16384

Script summary

Name	Hash	Size (Bytes)
νHead	f2dd4ade71e19c2310a86215aa78aea06463aca2d8b818af8dc1b8a4	12805
μHead	4abb8dedbcd6a6f03f4fe227300e2713d73b7680d47baa898b60d27a*	4971
νDeposit	c78e8c9205721eb3ef4410f3db9c6169fa6db497c24641d29c20529c	1615
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	9.95	3.29	0.50
2	5572	9.86	3.23	0.50
3	5665	10.55	3.46	0.51
5	5858	11.43	3.73	0.53
10	6341	13.61	4.42	0.57
50	10183	35.04	11.13	0.96
100	14983	61.91	19.53	1.45
114	16327	69.52	21.92	1.59

Cost of Increment Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	2321	20.59	7.33	0.47
2	2451	21.63	8.33	0.49
3	2582	22.64	9.31	0.51
5	2846	25.17	11.47	0.56
10	3501	29.59	16.19	0.66
50	8743	72.39	56.24	1.53
75	12020	97.80	80.86	2.05

Cost of Decrement Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	642	18.46	6.68	0.38
2	772	19.42	7.65	0.40
3	905	20.35	8.61	0.42
5	1167	22.31	10.57	0.46
10	1822	27.12	15.43	0.56
50	7064	68.30	54.95	1.41
75	10338	93.97	79.62	1.94

Close transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	669	17.76	11.66	0.41
2	800	18.76	12.65	0.43
3	931	19.69	13.61	0.45
5	1190	21.71	15.59	0.49
50	7090	67.81	60.10	1.44
75	10365	93.18	84.76	1.97

Contest transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	696	21.48	14.90	0.46
2	828	22.62	15.93	0.48
3	964	23.81	16.97	0.51
5	1226	26.01	19.00	0.55
10	1880	31.74	24.15	0.66
50	7121	79.69	65.78	1.58
67	9345	99.91	83.42	1.97

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	23.29	42.87	0.90
10	1	57	5678	25.63	45.39	0.93
10	5	284	5813	35.88	55.71	1.10
10	10	569	5984	49.89	68.99	1.31
10	20	1134	6318	82.42	96.97	1.79
1	20	1140	6045	76.20	95.00	1.72
5	20	1140	6169	78.96	95.88	1.75
10	20	1139	6323	82.42	96.97	1.79
20	20	1139	6634	89.74	99.26	1.88
50	15	854	7394	94.70	91.88	1.90

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	568	985	34.91	66.33	0.95
25	23	1309	1428	68.24	99.40	1.48
30	23	1309	1428	68.24	99.40	1.48
40	23	1308	1427	68.24	99.40	1.48
50	23	1310	1429	68.24	99.40	1.48
100	23	1310	1425	68.24	99.40	1.48
150	23	1310	1429	68.24	99.40	1.48
200	23	1310	1429	68.24	99.40	1.48
200	23	1310	1429	68.24	99.40	1.48

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	1050	1532	41.97	68.85	1.05
25	21	2037	2280	76.59	99.12	1.58
30	21	2583	2852	76.59	99.27	1.61
40	21	2394	2654	76.59	99.22	1.60
50	21	1995	2237	76.56	99.11	1.58
100	21	2184	2431	76.56	99.16	1.59
150	21	2562	2831	76.59	99.27	1.61
200	21	2436	2699	76.59	99.22	1.60
200	21	2058	2303	76.59	99.12	1.59

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	105	5524	21.97	44.27	0.89
5	485	5820	35.70	55.82	1.10
10	1230	6460	53.90	70.67	1.38
10	940	6170	53.78	70.57	1.37

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 2026-08-10 14:17:22.998892356 UTC

Baseline Scenario

Number of nodes	1
Number of txs	300
Avg. Confirmation Time (ms)	171.0
P99	173.7ms
P95	173.5ms
P50	171.1ms
Tx validation time p50 (ms)	107.5
End-to-end TPS	1704.13 tx/s
Backlog drain time (s)	0.2
Snapshots observed	3
Snapshots per second	17.04 /s
Avg txs per snapshot	100.0
Peak node RSS (MB)	143.3
Number of Invalid txs	0
Fanout outputs	2

Three local nodes

Number of nodes	3
Number of txs	900
Avg. Confirmation Time (ms)	872.1
P99	923.0ms
P95	922.6ms
P50	843.5ms
Tx validation time p50 (ms)	394.1
End-to-end TPS	963.66 tx/s
Backlog drain time (s)	0.9
Snapshots observed	3
Snapshots per second	3.21 /s
Avg txs per snapshot	300.0
Peak node RSS (MB)	147.9
Number of Invalid txs	0
Fanout outputs	4

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 2026-08-10 14:32:11.944874172 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	1193.10	n/a	24.5	24.9
Nodes=1, Constant, wait for tx valid	30	0.4	69.21	163.16	14.4	61.3
Nodes=1, Growing, fire and forget	30	0.0	635.62	n/a	46.5	46.9
Nodes=1, Growing, wait for tx valid	30	0.3	113.92	135.38	8.7	13.3
Nodes=1, Mixed, fire and forget	30	0.1	410.60	n/a	72.5	72.8
Nodes=1, Mixed, wait for tx valid	30	0.3	102.39	143.76	9.7	11.2
Nodes=2, Constant, fire and forget	60	0.0	1352.39	n/a	43.3	43.9
Nodes=2, Constant, wait for tx valid	60	1.1	54.05	62.45	36.8	116.2
Nodes=2, Growing, fire and forget	60	0.1	890.09	n/a	66.0	66.6
Nodes=2, Growing, wait for tx valid	60	0.6	93.72	92.89	21.1	28.1
Nodes=2, Mixed, fire and forget	60	0.1	950.56	n/a	61.8	62.5
Nodes=2, Mixed, wait for tx valid	60	0.7	91.19	85.04	21.8	45.2
Nodes=3, Constant, fire and forget	90	0.1	956.65	n/a	92.3	93.4
Nodes=3, Constant, wait for tx valid	90	1.8	50.46	58.37	58.1	190.1
Nodes=3, Growing, fire and forget	90	0.1	758.18	n/a	116.4	118.0
Nodes=3, Growing, wait for tx valid	90	1.6	57.31	57.57	51.7	144.1
Nodes=3, Mixed, fire and forget	90	0.1	808.60	n/a	104.6	110.3
Nodes=3, Mixed, wait for tx valid	90	2.4	38.22	41.47	78.3	359.1

Nodes=1, Constant, fire and forget

Number of nodes	1
Number of txs	30
Avg. Confirmation Time (ms)	24.5
P99	24.9ms
P95	24.9ms
P50	24.6ms
Tx validation time p50 (ms)	7.2
End-to-end TPS	1193.10 tx/s
Backlog drain time (s)	0.0
Snapshots observed	2
Snapshots per second	79.54 /s
Avg txs per snapshot	15.0
Peak node RSS (MB)	143.6
Number of Invalid txs	0
Fanout outputs	2

Nodes=1, Constant, wait for tx valid

Number of nodes	1
Number of txs	30
Avg. Confirmation Time (ms)	14.4
P99	139.4ms
P95	61.3ms
P50	5.6ms
Tx validation time p50 (ms)	1.9
End-to-end TPS	69.21 tx/s
Sustained TPS	163.16 tx/s
Backlog drain time (s)	0.0
Snapshots observed	30
Snapshots per second	69.21 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	143.6
Number of Invalid txs	0
Fanout outputs	2

Nodes=1, Growing, fire and forget

Number of nodes	1
Number of txs	30
Avg. Confirmation Time (ms)	46.5
P99	46.9ms
P95	46.9ms
P50	46.7ms
Tx validation time p50 (ms)	29.6
End-to-end TPS	635.62 tx/s
Backlog drain time (s)	0.0
Snapshots observed	2
Snapshots per second	42.37 /s
Avg txs per snapshot	15.0
Peak node RSS (MB)	143.0
Number of Invalid txs	0
Fanout outputs	31

Nodes=1, Growing, wait for tx valid

Number of nodes	1
Number of txs	30
Avg. Confirmation Time (ms)	8.7
P99	41.2ms
P95	13.3ms
P50	6.8ms
Tx validation time p50 (ms)	1.9
End-to-end TPS	113.92 tx/s
Sustained TPS	135.38 tx/s
Backlog drain time (s)	0.0
Snapshots observed	30
Snapshots per second	113.92 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	145.3
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
Avg. Confirmation Time (ms)	72.5
P99	72.8ms
P95	72.8ms
P50	72.7ms
Tx validation time p50 (ms)	58.2
End-to-end TPS	410.60 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	27.37 /s
Avg txs per snapshot	15.0
Peak node RSS (MB)	143.6
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
Avg. Confirmation Time (ms)	9.7
P99	70.9ms
P95	11.2ms
P50	6.3ms
Tx validation time p50 (ms)	1.9
End-to-end TPS	102.39 tx/s
Sustained TPS	143.76 tx/s
Backlog drain time (s)	0.0
Snapshots observed	30
Snapshots per second	102.39 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	143.9
Number of Invalid txs	0
Fanout outputs	2

Nodes=2, Constant, fire and forget

Number of nodes	2
Number of txs	60
Avg. Confirmation Time (ms)	43.3
P99	44.0ms
P95	43.9ms
P50	43.5ms
Tx validation time p50 (ms)	21.3
End-to-end TPS	1352.39 tx/s
Backlog drain time (s)	0.0
Snapshots observed	2
Snapshots per second	45.08 /s
Avg txs per snapshot	30.0
Peak node RSS (MB)	144.6
Number of Invalid txs	0
Fanout outputs	3

Nodes=2, Constant, wait for tx valid

Number of nodes	2
Number of txs	60
Avg. Confirmation Time (ms)	36.8
P99	225.1ms
P95	116.2ms
P50	19.8ms
Tx validation time p50 (ms)	4.5
End-to-end TPS	54.05 tx/s
Sustained TPS	62.45 tx/s
Backlog drain time (s)	0.0
Snapshots observed	60
Snapshots per second	54.05 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	143.8
Number of Invalid txs	0
Fanout outputs	3

Nodes=2, Growing, fire and forget

Number of nodes	2
Number of txs	60
Avg. Confirmation Time (ms)	66.0
P99	67.0ms
P95	66.6ms
P50	66.3ms
Tx validation time p50 (ms)	30.4
End-to-end TPS	890.09 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	29.67 /s
Avg txs per snapshot	30.0
Peak node RSS (MB)	144.8
Number of Invalid txs	0
Fanout outputs	62

Nodes=2, Growing, wait for tx valid

Number of nodes	2
Number of txs	60
Avg. Confirmation Time (ms)	21.1
P99	36.4ms
P95	28.1ms
P50	19.6ms
Tx validation time p50 (ms)	5.6
End-to-end TPS	93.72 tx/s
Sustained TPS	92.89 tx/s
Backlog drain time (s)	0.0
Snapshots observed	60
Snapshots per second	93.72 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	145.5
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
Avg. Confirmation Time (ms)	61.8
P99	62.5ms
P95	62.5ms
P50	62.2ms
Tx validation time p50 (ms)	18.0
End-to-end TPS	950.56 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	31.69 /s
Avg txs per snapshot	30.0
Peak node RSS (MB)	145.3
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
Avg. Confirmation Time (ms)	21.8
P99	53.3ms
P95	45.2ms
P50	18.6ms
Tx validation time p50 (ms)	5.0
End-to-end TPS	91.19 tx/s
Sustained TPS	85.04 tx/s
Backlog drain time (s)	0.0
Snapshots observed	60
Snapshots per second	91.19 /s
Avg txs per snapshot	1.0
Peak node RSS (MB)	145.7
Number of Invalid txs	0
Fanout outputs	3

Nodes=3, Constant, fire and forget

Number of nodes	3
Number of txs	90
Avg. Confirmation Time (ms)	92.3
P99	93.5ms
P95	93.4ms
P50	92.8ms
Tx validation time p50 (ms)	36.4
End-to-end TPS	956.65 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	21.26 /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
Avg. Confirmation Time (ms)	58.1
P99	206.4ms
P95	190.1ms
P50	26.0ms
Tx validation time p50 (ms)	6.3
End-to-end TPS	50.46 tx/s
Sustained TPS	58.37 tx/s
Backlog drain time (s)	0.0
Snapshots observed	61
Snapshots per second	34.20 /s
Avg txs per snapshot	1.5
Peak node RSS (MB)	145.3
Number of Invalid txs	0
Fanout outputs	4

Nodes=3, Growing, fire and forget

Number of nodes	3
Number of txs	90
Avg. Confirmation Time (ms)	116.4
P99	118.1ms
P95	118.0ms
P50	117.8ms
Tx validation time p50 (ms)	41.0
End-to-end TPS	758.18 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	16.85 /s
Avg txs per snapshot	45.0
Peak node RSS (MB)	145.3
Number of Invalid txs	0
Fanout outputs	0

Nodes=3, Growing, wait for tx valid

Number of nodes	3
Number of txs	90
Avg. Confirmation Time (ms)	51.7
P99	206.7ms
P95	144.1ms
P50	36.3ms
Tx validation time p50 (ms)	9.7
End-to-end TPS	57.31 tx/s
Sustained TPS	57.57 tx/s
Backlog drain time (s)	0.0
Snapshots observed	63
Snapshots per second	40.12 /s
Avg txs per snapshot	1.4
Peak node RSS (MB)	147.2
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
Avg. Confirmation Time (ms)	104.6
P99	110.3ms
P95	110.3ms
P50	102.7ms
Tx validation time p50 (ms)	41.4
End-to-end TPS	808.60 tx/s
Backlog drain time (s)	0.1
Snapshots observed	2
Snapshots per second	17.97 /s
Avg txs per snapshot	45.0
Peak node RSS (MB)	145.8
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
Avg. Confirmation Time (ms)	78.3
P99	378.0ms
P95	359.1ms
P50	32.9ms
Tx validation time p50 (ms)	8.5
End-to-end TPS	38.22 tx/s
Sustained TPS	41.47 tx/s
Backlog drain time (s)	0.0
Snapshots observed	62
Snapshots per second	26.33 /s
Avg txs per snapshot	1.5
Peak node RSS (MB)	147.0
Number of Invalid txs	0
Fanout outputs	4