fix: do not publish empty contract data

[alexghr]

This PR fixes the sequencer publishing contract for every transaction.

Fix #2970

[AztecBot]

Benchmark results

Metrics with a significant change:

• node_database_size_in_bytes (10): 3,646,072 (-31%)
• note_trial_decrypting_time_in_ms (8): 106 (+101%)

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 fd1f619f 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	45,444	179,588	716,132
l1_rollup_calldata_gas	220,896	866,288	3,447,800
l1_rollup_execution_gas	934,040	3,968,762	24,791,336
l2_block_processing_time_in_ms	1,327 (-13%)	5,110 (-1%)	21,365
note_successful_decrypting_time_in_ms	392 (+14%)	932 (-3%)	3,386 (-3%)
note_trial_decrypting_time_in_ms	⚠️ 106 (+101%)	60.0 (-35%)	134 (-4%)
l2_block_building_time_in_ms	14,841 (-1%)	60,242 (+1%)	238,631
l2_block_rollup_simulation_time_in_ms	10,484 (-1%)	42,701 (+2%)	169,409
l2_block_public_tx_process_time_in_ms	4,325 (-1%)	17,431 (+1%)	68,948

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	14,867 (-3%)	28,453 (-2%)
note_history_successful_decrypting_time_in_ms	2,156 (-6%)	4,211 (-8%)
note_history_trial_decrypting_time_in_ms	101 (-36%)	157 (-30%)
node_database_size_in_bytes	3,584,064 (-1%)	⚠️ 3,646,072 (-31%)
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	212 (-1%)	44,681	25,561
private-kernel-ordering	165 (-1%)	43,753	14,809
base-rollup	1,069	128,338	881
root-rollup	83.3 (+1%)	4,088	709
private-kernel-inner	292	71,208	25,561
public-kernel-private-input	206	31,863	25,561
public-kernel-non-first-iteration	204	31,905	25,561
merge-rollup	8.23 (-1%)	2,608	881

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	64 leaves	128 leaves	512 leaves	1024 leaves	2048 leaves	8192 leaves
batch_insert_into_append_only_tree_ms	11.2	19.4 (+16%)	13.7 (-2%)	18.4 (+2%)	23.5 (-2%)	50.0 (-1%)	98.3 (+27%)	243	468 (-1%)	909 (-1%)	3,580
batch_insert_into_indexed_tree_ms	N/A	N/A	N/A	63.8 (-2%)	N/A	59.5 (-1%)	110 (-1%)	360 (-1%)	749 (+1%)	1,414	5,583

Miscellaneous

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

Metric	0 deployed contracts	1 deployed contracts
tx_size_in_bytes	15,455	32,224

Transaction processing duration by data writes.

Metric	0 new commitments	1 new commitments
tx_pxe_processing_time_ms	378 (+1%)	1,080 (-1%)

Metric	1 public data writes
tx_sequencer_processing_time_ms	537

[PhilWindle]

Don't suppose we could invert the check, early return and reduce the nesting?