Implemented comprehensive state preservation to prevent temporary dropouts:
1. Node Grace Period (60s):
- Track last-online timestamp for each Proxmox node
- Preserve online status during grace period to prevent flapping
- Applied to all node status checks throughout codebase
2. Efficient Polling Preservation:
- Detect when cluster/resources returns empty arrays
- Preserve previous VMs/containers if had resources before
- Handles cluster health check failures gracefully
3. Traditional Polling Preservation:
- Updated preservation logic for per-node VM/container polling
- Triggers when zero resources returned regardless of node response
- Fixed issue where nodes responding with empty data bypassed preservation
Root cause: Intermittent Proxmox cluster health failures ("no healthy nodes
available") caused both efficient and traditional polling to return empty
arrays, immediately clearing all VMs/containers from state.
Changes:
- internal/monitoring/monitor.go: Added node grace period, efficient polling preservation
- internal/monitoring/monitor_polling.go: Fixed traditional polling preservation logic
Fixes frequent UI flickering where vmCount/containerCount would briefly drop to zero.
This change addresses intermittent "Guest details unavailable" and "Disk stats
unavailable" errors affecting users with large VM deployments (50+ VMs) or
high-load Proxmox environments.
Changes:
- Increased default guest agent timeouts (3-5s → 10-15s) to better handle
environments under load
- Added automatic retry logic (1 retry by default) for transient timeout failures
- Made all timeouts and retry count configurable via environment variables:
* GUEST_AGENT_FSINFO_TIMEOUT (default: 15s)
* GUEST_AGENT_NETWORK_TIMEOUT (default: 10s)
* GUEST_AGENT_OSINFO_TIMEOUT (default: 10s)
* GUEST_AGENT_VERSION_TIMEOUT (default: 10s)
* GUEST_AGENT_RETRIES (default: 1)
- Added comprehensive documentation in VM_DISK_MONITORING.md with configuration
examples for different deployment scenarios
These improvements allow Pulse to gracefully handle intermittent API timeouts
without immediately displaying errors, while remaining configurable for
different network conditions and environment sizes.
Fixes: https://github.com/rcourtman/Pulse/discussions/592
Implements structured logging package with LOG_LEVEL/LOG_FORMAT env support, debug level guards for hot paths, enriched error messages with actionable context, and stack trace capture for production debugging. Improves observability and reduces log overhead in high-frequency polling loops.
Replaces immediate polling with queue-based scheduling:
- TaskQueue with min-heap (container/heap) for NextRun-ordered execution
- Worker goroutines that block on WaitNext() until tasks are due
- Tasks only execute when NextRun <= now, respecting adaptive intervals
- Automatic rescheduling after execution via scheduler.BuildPlan
- Queue depth tracking for backpressure-aware interval adjustments
- Upsert semantics for updating scheduled tasks without duplicates
Task 6 of 10 complete (60%). Ready for error/backoff policies.
Adds freshness metadata tracking for all monitored instances:
- StalenessTracker with per-instance last success/error/mutation timestamps
- Change hash detection using SHA1 for detecting data mutations
- Normalized staleness scoring (0-1 scale) based on age vs maxStale
- Integration with PollMetrics for authoritative last-success data
- Wired into all poll functions (PVE/PBS/PMG) via UpdateSuccess/UpdateError
- Connected to scheduler as StalenessSource implementation
Task 4 of 10 complete. Ready for adaptive interval logic.
