feat(host-rpc): add backpressure controls to notifier#123
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Bound concurrent RPC block fetches with configurable max_rpc_concurrency (default 8) and coalesce stale subscription headers via Latest<S> stream adapter to prevent slow-consumer backlog buildup. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Non-blocking nitpicks only.
| /// Set the maximum number of concurrent RPC block fetches (default: 8). | ||
| /// | ||
| /// Values below 1 are clamped to 1. | ||
| pub const fn with_max_rpc_concurrency(mut self, max_rpc_concurrency: usize) -> Self { |
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We could add with_max_rpc_concurrency to the doc example above here.
Also, we clamp here, but not in with_backfill_batch_size or with_buffer_capacity which is a bit inconsistent.
…mple Add consistent minimum-value clamping (to 1) for buffer_capacity and backfill_batch_size to match max_rpc_concurrency. Add the missing with_max_rpc_concurrency call to the builder doc example. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
Adds backpressure controls to
RpcHostNotifierto prevent unbounded RPC fan-out and stale header processing. Closes ENG-2104.FuturesOrderedwithstream::buffered(max_rpc_concurrency)(default 8, configurable viaSIGNET_HOST_MAX_RPC_CONCURRENCY)Latest<S>stream adapter drains buffered subscription headers and yields only the most recent, discarding stale intermediateshost_rpc.headers_coalescedcounter tracks skipped headersTest plan
Latest<S>pass (cargo t -p signet-host-rpc)headers_coalescedmetric under load to confirm coalescing behavior🤖 Generated with Claude Code