Fuel-Executor Metrics

[ControlCplusControlV]

Scope changes:

The following metrics will be added

• histogram: gas per block
• histogram: size per block
• histogram: fee/coinbase per block
• histogram: txs per block

The following metric will not be added as a part of this issue. We will discuss if we want some more sophisticated mechanism to measure other operations that touch DB

• histogram: I/O (db) time per block

The following metric will not be added

• gas prices
  Rationale: Fuel-Executor Metrics #807 (comment)

cc: @acerone85 @MitchTurner

[rafal-ch]

Question regarding "histogram: I/O (db) time per block" - what we actually try to measure here?

Are we interested in how much time was spent on the DB operations in Importer::execute_and_commit?

This would require measuring call-chain such as:

• verify_block_fields()
  • block_header_merkle_root()
  • block_header()
• validate()
  • native_validate_inner() -or- wasm_validate_inner()
  • potential call to get_module() in validate_inner()
• _commit_result()
• possibly more...

And then, next to

importer_metrics().execute_and_commit_duration.observe(time);

we can add

importer_metrics().execute_and_commit_db_duration.observe(time);

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Alternatively, we might want to work on a generic method of opt-in for measured DB reads, like trait MeasuredStorageInspect or similar.

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Any opinions? @xgreenx @acerone85

[acerone85]

The gas price is not available from the block importer, but rather from the producer.
Should we add metrics for the block producer too @MitchTurner?

[rafal-ch]

Also, what would be the suggested values for FEE_BUCKETS and GAS_PRICE_BUCKETS buckets.

[rymnc]

Also, what would be the suggested values for FEE_BUCKETS and GAS_PRICE_BUCKETS buckets.

cc: @MitchTurner

[MitchTurner]

The gas price is not available from the block importer, but rather from the producer.
Should we add metrics for the block producer too @MitchTurner?

Perhaps we put the metrics on the gas-price-service since it holds the most context? It's available from the producer, the tx-pool, and graphql, but they all get it served from the gas price service.

[rafal-ch]

As for now, we're not gonna be doing the "gas price" metric. Rationale: Since we don't have DA gas price yet, we can derive the total gas price from gas used and fee.

[MitchTurner]

Everything looks completed :)