Optimize VM performance with parallel checks and batch operations

[alexander-acker]

Summary

This PR implements several performance optimizations for VM management across Lima and WSL sandboxes, focusing on reducing startup time and improving responsiveness through parallelization and batching.

Key Changes

Parallel Dependency Checks

• Lima and WSL bridges: Refactored status checks to use Promise.allSettled() for parallel execution of Node.js, Python, and claude-code availability checks
• Combined Python/pip checks: Merged separate Python and pip version checks into a single shell invocation to reduce SSH/WSL overhead
• Reduces status check time from sequential to parallel execution

Agent Startup Optimization

• Exponential backoff: Replaced fixed 500ms retry delays with exponential backoff (starting at 100ms, capping at 2s) for agent readiness polling
• Faster initial check: Reduced initial wait from 1000ms to 200ms before first readiness check
• Significantly speeds up agent startup, especially on fast systems

Batch Operation Support

• New sendBatchRequest() method: Added to both LimaBridge and WSLBridge for executing multiple independent operations in a single IPC round-trip
• Agent batch handler: Implemented batch case in both lima-agent and wsl-agent to process arrays of operations sequentially and return results
• Reduces IPC overhead when multiple operations are needed

Sync Optimizations

• Faster rsync flags: Changed from -av to -rlptD (skips owner/group preservation) for cross-filesystem syncs in both LimaSync and SandboxSync
• Combined stats collection: Merged separate find and du commands into a single shell invocation to get file count and total size
• Reduces SSH/WSL command overhead during sync operations

Bootstrap Optimization

• Selective status updates: After starting Lima instance, only re-check dependency availability instead of full status re-check
• Avoids redundant limactl list and SSH connection checks when instance state is already known

Testing

Added comprehensive test suite (vm-performance.test.ts) verifying:

• Parallel check implementation using Promise.allSettled
• Combined Python/pip check patterns
• Exponential backoff configuration
• Batch operation support in agents and bridges
• Optimized rsync flags and combined stats commands
• Bootstrap selective update behavior

https://claude.ai/code/session_01VXvXaDFPiDEJQy4b8FU7so