Streaming events

[ch1bo]

Changes I made originally for the hydra-doom project to load all events in state (12GB+ in that use case) with constant memory using conduit streams.

There is a big TODO on this: IOSim s does not have a MonadUnliftIO instance and its not impossible to have one. We need to change the interface further such that we can compose createHydraNode and hydrate functions with in-memory EventSource variants.

A bit of a wart: The mkProjection does run the conduit for each projection, instead we should run the conduit once and build the projected in-memory read/query model once.

Also, the change here is not constant-memory as the ServerOutput history is still kept fully in memory. But this is a different story and should be covered by #1618

---

• 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]

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	2025-02-04 18:46:54.994272593 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	10.98	3.42	0.53
2	6295	13.04	4.04	0.56
3	6496	15.37	4.76	0.59
5	6897	20.19	6.25	0.66
10	7904	30.97	9.53	0.82
40	13935	98.36	30.21	1.78

Commit transaction costs

This uses ada-only outputs for better comparability.

UTxO	Tx size	% max Mem	% max CPU	Min fee ₳
1	558	2.44	1.16	0.20
2	743	3.38	1.73	0.22
3	918	4.36	2.33	0.24
5	1276	6.41	3.60	0.28
10	2177	12.13	7.25	0.40
54	10070	98.61	68.52	1.88

CollectCom transaction costs

Parties	UTxO (bytes)	Tx size	% max Mem	% max CPU	Min fee ₳
1	57	525	25.67	7.41	0.43
2	114	636	35.89	10.22	0.54
3	171	751	45.82	12.99	0.65
4	227	862	56.25	15.85	0.76
5	284	969	65.33	18.43	0.85
6	336	1081	78.33	21.93	0.99
7	393	1192	89.09	25.03	1.10
8	449	1307	96.61	27.14	1.18

Cost of Increment Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	1818	25.03	8.22	0.49
2	2007	27.74	9.80	0.53
3	2147	29.19	10.93	0.56
5	2399	33.10	13.42	0.62
10	3212	45.04	20.71	0.80
37	7189	97.24	55.40	1.65

Cost of Decrement Transaction

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	623	23.95	7.61	0.43
2	735	24.81	8.48	0.44
3	873	26.53	9.62	0.47
5	1176	31.77	12.41	0.55
10	2185	47.47	20.05	0.77
39	5951	91.97	51.65	1.53

Close transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	716	29.15	9.22	0.48
2	833	33.51	11.22	0.54
3	948	32.78	11.64	0.54
5	1226	39.25	14.96	0.63
10	1954	49.71	21.56	0.79
36	5747	99.08	54.72	1.60

Contest transaction costs

Parties	Tx size	% max Mem	% max CPU	Min fee ₳
1	676	35.95	11.00	0.55
2	840	38.11	12.32	0.58
3	1006	40.95	13.93	0.63
5	1265	45.41	16.59	0.69
10	2010	57.43	23.72	0.87
27	4603	99.14	48.33	1.50

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	5895	24.12	7.83	0.66
2	6095	37.39	12.32	0.81
3	6303	49.02	16.24	0.94
4	6324	56.08	18.45	1.01
5	6583	67.80	22.41	1.15
6	6664	73.09	24.15	1.21
7	6755	84.03	27.73	1.33
8	6822	91.28	30.07	1.40

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	1	57	6125	22.38	7.49	0.65
10	10	569	6430	40.50	14.57	0.87
10	30	1707	7110	83.57	31.25	1.36
10	36	2048	7313	96.81	36.36	1.52

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 2025-02-04 18:49:43.655420393 UTC

Baseline Scenario

Number of nodes	1
Number of txs	300
Avg. Confirmation Time (ms)	4.998232416
P99	9.671592719999994ms
P95	6.093833300000002ms
P50	4.8482485ms
Number of Invalid txs	0

Three local nodes

Number of nodes	3
Number of txs	900
Avg. Confirmation Time (ms)	24.112336945
P99	118.40399658ms
P95	31.67434695ms
P50	21.5728845ms
Number of Invalid txs	0