perf: Use O(1) ring buffer cache for block hashes instead of BTreeMap#3299
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rakita merged 4 commits intobluealloy:mainfrom Jan 15, 2026
Merged
perf: Use O(1) ring buffer cache for block hashes instead of BTreeMap#3299rakita merged 4 commits intobluealloy:mainfrom
rakita merged 4 commits intobluealloy:mainfrom
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Merging this PR will degrade performance by 3.07%
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I dont thing benchmarks cover past block hashes so this is okay |
rakita
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Jan 14, 2026
rakita
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left few nits, but in general lgtm
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do |
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Fascinating |
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rakita
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| if let Some(entry) = self.block_hashes.get(&number) { | ||
| return Ok(*entry); | ||
| if let Some(entry) = self.block_hashes.get(number) { | ||
| return Ok(FixedBytes(*entry)); |
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Interesting artefact, can fix it later
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The ring buffer cache introduced in bluealloy#3299 was initialized with `(0, B256::ZERO)` for all entries. This caused `get(0)` to incorrectly match the default entry and return `B256::ZERO` instead of `None`, preventing the database fallback from being invoked. This is a consensus bug for any chain at low block numbers (< 256) where BLOCKHASH(0) should return the genesis block hash. Fix: Use `Option<B256>` instead of `B256` to explicitly distinguish between "not cached" (`None`) and "cached with value" (`Some(hash)`). 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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The ring buffer cache introduced in bluealloy#3299 was initialized with `(0, B256::ZERO)` for all entries. This caused `get(0)` to incorrectly match the default entry and return `B256::ZERO` instead of `None`, preventing the database fallback from being invoked. This is a consensus bug for any chain at low block numbers (< 256) where BLOCKHASH(0) should return the genesis block hash. Fix: Use `Option<B256>` instead of `B256` to explicitly distinguish between "not cached" (`None`) and "cached with value" (`Some(hash)`). 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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…3319) * fix(database): BlockHashCache incorrectly returns zero for block 0 The ring buffer cache introduced in #3299 was initialized with `(0, B256::ZERO)` for all entries. This caused `get(0)` to incorrectly match the default entry and return `B256::ZERO` instead of `None`, preventing the database fallback from being invoked. This is a consensus bug for any chain at low block numbers (< 256) where BLOCKHASH(0) should return the genesis block hash. Fix: Use `Option<B256>` instead of `B256` to explicitly distinguish between "not cached" (`None`) and "cached with value" (`Some(hash)`). 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com> * refactor: use Option<u64> for block number in BlockHashCache Address review feedback: - Use Option<u64> for block number instead of Option<B256> for hash - Keep const on insert and get functions * style: simplify get() comparison Use direct Option comparison as suggested in review. --------- Co-authored-by: Claude <noreply@anthropic.com> Co-authored-by: rakita <dragan0rakita@gmail.com>
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Replaces the
BTreeMap<u64, B256>used for block hash caching inStatewith a newBlockHashCachestruct that implements a fixed-size ring buffer(Technically anyway)from benchmark: