Make Soroban metric batching code lock-free.

[dmkozh]

Description

The previous attempt at batching Soroban metrics still had some locks and was overall more convoluted than it needs to be. With this change we simply give every thread its own metrics batch to write to, and then cleanly move the batches to the publish step for the merge and Medida export. This is slightly more plumbing, but as a result we get much more straightforward code.

Checklist

• Reviewed the contributing document
• Rebased on top of master (no merge commits)
• Ran clang-format v8.0.0 (via make format or the Visual Studio extension)
• Compiles
• Ran all tests
• If change impacts performance, include supporting evidence per the performance document

[Copilot]

Pull request overview

Refactors Soroban metrics collection to use thread-local accumulators and publish merged results after ledger close.

Changes:

• Introduces SorobanApplyMetrics and SorobanMetricsRegistry.
• Plumbs accumulators through transaction and operation apply paths.
• Merges worker metrics before Medida publication.

Reviewed changes

Copilot reviewed 27 out of 27 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/transactions/TransactionFrameBase.h	Extends apply interfaces with metrics.
src/transactions/TransactionFrame.h	Updates transaction method declarations.
src/transactions/TransactionFrame.cpp	Records metrics in supplied accumulators.
src/transactions/test/TransactionTestFrame.h	Updates test wrapper interfaces.
src/transactions/test/TransactionTestFrame.cpp	Supplies test-local accumulators.
src/transactions/RestoreFootprintOpFrame.h	Updates restore-operation interfaces.
src/transactions/RestoreFootprintOpFrame.cpp	Redirects restore metrics.
src/transactions/ParallelApplyUtils.h	Extends parallel-state interfaces.
src/transactions/ParallelApplyUtils.cpp	Passes metrics during pre-apply.
src/transactions/OperationFrame.h	Extends operation apply interfaces.
src/transactions/OperationFrame.cpp	Forwards operation metrics.
src/transactions/InvokeHostFunctionOpFrame.h	Updates host-function interfaces.
src/transactions/InvokeHostFunctionOpFrame.cpp	Accumulates host-function metrics locally.
src/transactions/FeeBumpTransactionFrame.h	Updates fee-bump interfaces.
src/transactions/FeeBumpTransactionFrame.cpp	Forwards metrics to inner transactions.
src/transactions/ExtendFootprintTTLOpFrame.h	Updates TTL-extension interfaces.
src/transactions/ExtendFootprintTTLOpFrame.cpp	Redirects TTL metrics.
src/test/fuzz/targets/TxFuzzTarget.cpp	Supplies fuzz-local metrics.
src/main/AppConnector.h	Exposes renamed metrics registry.
src/main/AppConnector.cpp	Returns renamed registry type.
src/ledger/SorobanMetrics.h	Defines accumulators and registry.
src/ledger/SorobanMetrics.cpp	Implements merging and publication.
src/ledger/LedgerManagerImpl.h	Extends ledger-apply metrics plumbing.
src/ledger/LedgerManagerImpl.cpp	Collects, merges, and publishes metrics.
src/ledger/LedgerManager.h	Updates ledger manager interfaces.
src/ledger/InMemorySorobanState.h	Uses renamed registry type.
src/ledger/InMemorySorobanState.cpp	Updates registry parameters.

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[Copilot]

Pull request overview

Copilot reviewed 27 out of 27 changed files in this pull request and generated 1 comment.

Suppressed comments (2)

src/transactions/TransactionFrame.cpp:2167

• This timer no longer honors DISABLE_SOROBAN_METRICS_FOR_TESTING: the clock reads and vector append still run and the samples are published, even though this switch exists specifically to remove metric overhead from apply-load benchmarks. The previous BatchedTimerScope was also RAII, whereas the append at line 2198 is skipped when the exception handler below converts an apply exception into txINTERNAL_ERROR. Please make the local timer conditional and scope-based so disabled runs do no timing/allocation and exceptional applies retain their timer sample.

        auto applyStart = std::chrono::steady_clock::now();

src/ledger/LedgerManagerImpl.cpp:2632

• This transaction timer now runs unconditionally, so DISABLE_SOROBAN_METRICS_FOR_TESTING still pays for two clock reads, vector growth, and later Medida publication per parallel transaction. That regresses the benchmark switch’s documented purpose and differs from the sequential apply timer, which still checks the flag. Guard both timing and sample insertion with config.DISABLE_SOROBAN_METRICS_FOR_TESTING.

        auto applyStart = std::chrono::steady_clock::now();

[Copilot]

Pull request overview

Copilot reviewed 27 out of 27 changed files in this pull request and generated no new comments.

Suppressed comments (1)

src/ledger/LedgerManagerImpl.cpp:2682

• This is a performance-focused change to the parallel apply hot path, but the PR provides no benchmark evidence that it improves throughput/latency without regression. CONTRIBUTING.md:56-60 requires such evidence for performance-impacting changes; please include representative before/after results, especially since the new per-cluster vector storage and merge may trade lock contention for allocation/cache costs.

    // Stages may contain a different number of clusters, so we ensure that
    // there is a corresponding metrics entry for each cluster.
    if (sorobanApplyMetricsPerThread.size() < stage.numClusters())
    {
        sorobanApplyMetricsPerThread.resize(stage.numClusters());