Commit Proxy Startup

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Deploys commit proxies for horizontal transaction scalability.

The Commit Proxy Startup phase deploys multiple commit proxies across cluster nodes to enable horizontal transaction processing. Unlike the singleton sequencer, commit proxies can run in parallel to handle increased transaction volume.

Scalability Through Distribution

Multiple commit proxies work together to process transactions efficiently:

  • Parallel Processing: Each commit proxy handles transaction batches independently
  • Load Distribution: Incoming transactions spread across available commit proxies
  • Independent Operations: Commit proxies coordinate with resolvers and log servers separately

Fault-Tolerant Deployment

Commit proxies deploy using round-robin assignment across coordination-capable nodes to ensure:

  • Physical Isolation: Hardware failures can't eliminate all transaction processing
  • Resource Distribution: Prevents resource contention on individual nodes
  • Network Resilience: Distributed commit proxies maintain availability during network issues

Controlled Startup

Deployed commit proxies remain locked until the Transaction System Layout phase activates them. This prevents:

  • Premature Processing: Transactions can't start before the complete pipeline is ready
  • Incomplete Coordination: Commit proxies wait for full system layout information
  • Recovery Conflicts: Locked commit proxies can't interfere with ongoing recovery

Critical Requirements

At least one commit proxy must start successfully or the cluster cannot accept transactions. The phase monitors coordination node availability and ensures minimum viable capacity before proceeding.

Implementation: lib/bedrock/control_plane/director/recovery/commit_proxy_startup_phase.ex

Next Phase: Resolver Startup - Deploy MVCC conflict detection components