starknet_committer,apollo_committer: add timers for fetch patricia paths

[ArielElp]

No description provided.

[reviewable-StarkWare]

This change is 

[ArielElp]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• apollo_committer: add new request handler #14003
• starknet_committer: delete patricia paths on reverts #14002
• starknet_committer,apollo_committer: add timers for fetch patricia paths #14189 👈 (View in Graphite)
• starknet_committer: underlying logic of the new read witnesses and commit endpoint #14001
• starknet_committer: extract metadata construction to a function #14000
• starknet_committer: extract commit plan to commit_or_load #13999
• starknet_committer: read and write patricia paths to index db #13998
• starknet_committer: db keys for proofs and accessed keys digest #13997
• apollo_committer_types: add patricia proofs request and response types #13996
• starknet_committer: add patricia paths forest reader/writer traits #13995
• starknet_committer: define StarknetForestProofs serde #13994
• starknet_committer: compute and store accessed keys digest #13993
• starknet_committer: add utility that returns sorted leaf indices #13992
• starknet_committer: abstract fetch_all_patricia_paths #13991
• starknet_patricia_storage: two layer storage #13990
• starknet_committer: move fetch_patricia_paths tests #13960
• starknet_committer: fetch patricia paths tests #13959
• starknet_committer: support both layouts in fetch_patricia_paths #13958
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[cursor]

PR Summary

Low Risk
Observability-only changes around witness path collection; no commit logic or persistence behavior changes beyond how witness counts are aggregated for logging/measurements.

Overview
Adds per-phase timing for Patricia witness collection in the OS-input commit path (read_paths_and_commit_block), keyed by global root before and after state application.

The measurement layer gains Action::FetchPatriciaPaths(HashOutput) with per-root timers and FetchPatriciaPathsMeasurement entries on BlockMeasurement. Apollo committer starts/stops these around pre- and post-commit fetch_patricia_witnesses calls and uses StarknetForestProofs::len() for witness counts in logs and stop measurements. Existing Prometheus update_metrics still ignores the new field (..).

Risk: Low—observability-only on the commit hot path; witness log counts now use len() (classes/contract nodes + storage proof nodes, not contract trie leaves).

^{Reviewed by Cursor Bugbot for commit b3e1cb3. Bugbot is set up for automated code reviews on this repo. Configure here.}

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, have a team admin enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit e8159c4. Configure here.}

[yoavGrs]

@yoavGrs reviewed 1 file and all commit messages, and made 5 comments.
Reviewable status: 1 of 3 files reviewed, 5 unresolved discussions (waiting on ArielElp).

---

crates/apollo_committer/src/committer.rs line 560 at r2 (raw file):

                    .ok();

                block_measurements.start_measurement(Action::EndToEnd);

The end-to-end measurement should include the new actions.

Code quote:

block_measurements.start_measurement(Action::EndToEnd);

---

crates/apollo_committer/src/committer.rs line 659 at r2 (raw file):

fn update_metrics(
    height: BlockNumber,
    BlockMeasurement { n_reads, n_writes, durations, modifications_counts, .. }: &BlockMeasurement,

And add a todo to consider including it in the metrics.

Suggestion:

, _fetch_patricia_paths_measurements }

---

crates/starknet_committer/src/block_committer/measurements_util.rs line 16 at r2 (raw file):

    Compute,
    Write,
    FetchPatriciaPaths(HashOutput),

Gate it?

Code quote:

FetchPatriciaPaths(HashOutput),

---

crates/starknet_committer/src/block_committer/measurements_util.rs line 25 at r2 (raw file):

    pub compute_timer: Option<Instant>,
    pub writer_timer: Option<Instant>,
    pub fetch_patricia_paths_timers: HashMap<HashOutput, Option<Instant>>,

If you save the timer by hash, how do you know what is the first read and what is the second? The hash itself is not interesting.

Keep it simple with two new timers?

Code quote:

pub fetch_patricia_paths_timers: HashMap<HashOutput, Option<Instant>>,

---

crates/starknet_committer/src/block_committer/measurements_util.rs line 121 at r2 (raw file):

    pub root: HashOutput,
    pub duration: f64,
    pub n_entries: usize,

There are structs for durations (BlockDurations) and for counts (BlockModificationsCounts).

Code quote:

    pub duration: f64,
    pub n_entries: usize,