feat: add semaphore for blocking IO requests#20289
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Adds configurable limit for concurrent blocking IO requests (eth_call, eth_estimateGas, etc.) to prevent tokio blocking thread pool exhaustion. Configuration: - New config: max_blocking_io_requests (default: 256) - CLI arg: --rpc.max-blocking-io-requests - Semaphore limits concurrent blocking IO operations Trait additions to SpawnBlocking: - blocking_io_task_guard(): Returns blocking IO semaphore - acquire_owned_blocking_io(): Acquires single permit - acquire_many_owned_blocking_io(n): Acquires multiple permits - acquire_weighted_blocking_io(weight): Weighted permit acquisition that divides total permits by weight to limit concurrent requests The weighted variant ensures at least (weight - 1) permits remain available when total_permits divides evenly by weight, preventing complete semaphore exhaustion. Applied to: - eth_call: Uses single permit acquisition - eth_getProof: Uses weighted acquisition (weight=5)
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shekhirin
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| Ok(async move { | ||
| let _permit = self | ||
| .acquire_owned() | ||
| .acquire_weighted_blocking_io(5) |
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this feels like a magic number, can you elaborate why it's 5?
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this basically enforces most 5 concurrent requests for this endpoint, while still leaving permits available
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can we make this configurable? I expect some users have more than 5 concurrent eth_getProof and it's expected behaviour that they're ready for in terms of RAM
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I can restore the previous behaviour by allocating the other semaphore
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…number * upstream: (203 commits) feat(node-core): make rpc server args customizable (paradigmxyz#20312) feat: add `account_history_in_rocksdb` field to `StorageSettings` (paradigmxyz#20282) feat(engine): Add BAL stub methods to ExecutionPayload and BlockOrPayload (paradigmxyz#20311) docs: fix misleading links (paradigmxyz#20300) ci: add more sccache (paradigmxyz#20316) feat: bump alloy-evm (paradigmxyz#20314) feat: allow larger ws frames on client side (paradigmxyz#20307) docs: add architecture diagrams to ExEx documentation (paradigmxyz#20193) feat: add semaphore for blocking IO requests (paradigmxyz#20289) ci: scale down depot runners (paradigmxyz#20295) perf: fetch header directly (paradigmxyz#20294) docs(exex): fix DebugApi comment (paradigmxyz#20296) feat: add support for testing_ rpc namespace and testing_buildBlockV1 (paradigmxyz#20094) chore: update engine_getBlobs metric (paradigmxyz#20290) chore(optimism): move predeploy constant to op-alloy (paradigmxyz#20181) docs: fix stages order and add missing EraStage (paradigmxyz#20283) docs: improve map_add_ons method documentation (paradigmxyz#20248) feat: add `transaction_hash_numbers_in_rocksdb` field to `StorageSettings` (paradigmxyz#20209) docs: clarify network mode, tx gossip and NAT (paradigmxyz#20247) feat: add support for debug_getBadBlock (paradigmxyz#20177) ...
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Adds settings for explicitly limiting concurrent tokio blocking tasks intended for IO (for now enabled for ethcall)
Note: this isnt yet enforced for all spawned tasks and should be applied selectively, gonna use this to investigate #20059
closes #20090
see also #20059