chore(aztec-nr): clarify in comments that nullifier computation does not need to include siloed note-hash for protocol security

[dbanks12]

Resolves #2666

[dbanks12]

Apologies for the delay on this.... I kind of forgot about it until now 😬

@LHerskind should I mention this in the docs somewhere too? If so where should it go? Limitations doesn't feel like the right place for this info.

[LHerskind]

Apologies for the delay on this.... I kind of forgot about it until now 😬

@LHerskind should I mention this in the docs somewhere too? If so where should it go? Limitations doesn't feel like the right place for this info.

Ideally it should be in the docs when we are talking about custom notes, but not sure that page is actually created 😅 Don't seem so.

[iAmMichaelConnor]

Please could we explain why the siloed note hash isn't needed? It's not obvious to me

[LHerskind]

@dbanks12 will you address this one, or can I just close it?

[dbanks12]

Don't think this really belongs in docs, but I updated the comment. If you think we should copy-paste this to the YP, lmk. Doesn't feel like it belongs in the Nullifier Tree section. I think a comment is sufficient.

[AztecBot]

Benchmark results

Metrics with a significant change:

• batch_insert_into_append_only_tree_16_depth_ms (8): 16.5 (+30%)
• batch_insert_into_append_only_tree_16_depth_hash_ms (8): 0.699 (+31%)

Detailed results

All benchmarks are run on txs on the Benchmarking contract on the repository. Each tx consists of a batch call to create_note and increment_balance, which guarantees that each tx has a private call, a nested private call, a public call, and a nested public call, as well as an emitted private note, an unencrypted log, and public storage read and write.

This benchmark source data is available in JSON format on S3 here.

Values are compared against data from master at commit 237f870c and shown if the difference exceeds 1%.

L2 block published to L1

Each column represents the number of txs on an L2 block published to L1.

Metric	8 txs	32 txs	128 txs
l1_rollup_calldata_size_in_bytes	54,212	214,436	855,332
l1_rollup_calldata_gas	259,880	1,019,768	4,060,076
l1_rollup_execution_gas	354,066	1,139,216	4,281,477
l2_block_processing_time_in_ms	1,222 (+1%)	4,592 (-9%)	18,194
note_successful_decrypting_time_in_ms	209 (+3%)	572 (-1%)	2,044 (+4%)
note_trial_decrypting_time_in_ms	25.5 (+59%)	109 (-8%)	193 (+17%)
l2_block_building_time_in_ms	16,226 (+2%)	64,086 (+1%)	260,893 (+1%)
l2_block_rollup_simulation_time_in_ms	12,390 (+1%)	49,017 (+1%)	200,345 (+1%)
l2_block_public_tx_process_time_in_ms	3,801 (+3%)	14,987 (+2%)	60,280 (+3%)

L2 chain processing

Each column represents the number of blocks on the L2 chain where each block has 16 txs.

Metric	5 blocks	10 blocks
node_history_sync_time_in_ms	15,429	30,666 (+4%)
note_history_successful_decrypting_time_in_ms	1,323 (-8%)	2,611 (+1%)
note_history_trial_decrypting_time_in_ms	133 (-15%)	180 (-31%)
node_database_size_in_bytes	19,091,536	36,233,296
pxe_database_size_in_bytes	29,923	59,478

Circuits stats

Stats on running time and I/O sizes collected for every circuit run across all benchmarks.

Circuit	circuit_simulation_time_in_ms	circuit_input_size_in_bytes	circuit_output_size_in_bytes
private-kernel-init	242	44,664	27,457
private-kernel-ordering	156	45,777	14,627
base-rollup	1,309	175,344	933
root-rollup	71.9	4,192	825
private-kernel-inner	307 (-1%)	73,099	27,457
public-kernel-app-logic	188	32,254	25,379
merge-rollup	5.88 (+1%)	2,712	933

Tree insertion stats

The duration to insert a fixed batch of leaves into each tree type.

Metric	1 leaves	2 leaves	8 leaves	16 leaves	32 leaves	128 leaves	64 leaves	512 leaves	1024 leaves	2048 leaves	8192 leaves
batch_insert_into_append_only_tree_16_depth_ms	9.96	10.4 (-10%)	⚠️ 16.5 (+30%)	16.9 (+1%)	22.2	78.2 (-4%)	N/A	N/A	N/A	N/A	N/A
batch_insert_into_append_only_tree_16_depth_hash_count	16.9	17.5	23.0	31.6	47.0	143	N/A	N/A	N/A	N/A	N/A
batch_insert_into_append_only_tree_16_depth_hash_ms	0.576	0.577 (-10%)	⚠️ 0.699 (+31%)	0.521 (+1%)	0.463	0.536 (-4%)	N/A	N/A	N/A	N/A	N/A
batch_insert_into_append_only_tree_32_depth_ms	N/A	N/A	N/A	N/A	N/A	72.3 (-2%)	46.3	236 (+1%)	449 (+1%)	875	3,462 (+1%)
batch_insert_into_append_only_tree_32_depth_hash_count	N/A	N/A	N/A	N/A	N/A	159	96.0	543	1,055	2,079	8,223
batch_insert_into_append_only_tree_32_depth_hash_ms	N/A	N/A	N/A	N/A	N/A	0.445 (-2%)	0.473	0.429 (+2%)	0.419	0.415	0.413
batch_insert_into_indexed_tree_20_depth_ms	N/A	N/A	N/A	N/A	N/A	101	56.4 (+1%)	340 (-1%)	673 (+1%)	1,328 (-1%)	5,275
batch_insert_into_indexed_tree_20_depth_hash_count	N/A	N/A	N/A	N/A	N/A	197	104	691	1,363	2,707	10,771
batch_insert_into_indexed_tree_20_depth_hash_ms	N/A	N/A	N/A	N/A	N/A	0.477	0.493 (+1%)	0.460 (-1%)	0.461 (+1%)	0.458 (-1%)	0.456 (-1%)
batch_insert_into_indexed_tree_40_depth_ms	N/A	N/A	N/A	N/A	62.6 (+1%)	N/A	N/A	N/A	N/A	N/A	N/A
batch_insert_into_indexed_tree_40_depth_hash_count	N/A	N/A	N/A	N/A	110	N/A	N/A	N/A	N/A	N/A	N/A
batch_insert_into_indexed_tree_40_depth_hash_ms	N/A	N/A	N/A	N/A	0.540	N/A	N/A	N/A	N/A	N/A	N/A

Miscellaneous

Transaction sizes based on how many contracts are deployed in the tx.

Metric	0 deployed contracts
tx_size_in_bytes	18,431

Transaction processing duration by data writes.

Metric	0 new note hashes	1 new note hashes
tx_pxe_processing_time_ms	2,510 (-1%)	1,310

Metric	0 public data writes	1 public data writes
tx_sequencer_processing_time_ms	0.0358 (+1%)	464 (+1%)

[LHerskind]

Ship it