Enum CheckpointReason

Namespace

Typhon.Profiler

Assembly

Typhon.Profiler.dll

What triggered a checkpoint cycle. Carried as the reason byte on CheckpointCycle spans.

public enum CheckpointReason : byte

Fields

DirtyPagePressure = 3

The page cache reached ResourceOptions.CheckpointDirtyPageThresholdPercent writeback debt, so the cycle ran early rather than waiting out the timer (#830).

Distinct from Forced on purpose. Forced covers the back-pressure escape hatch, which fires only once the cache is already 100 % dirty and an allocation is blocked; this fires at a threshold, before anything is stalled. Reading them as one number hides whether the trigger is doing its job or the engine is repeatedly falling off the cliff it exists to prevent.

Forced = 1

Explicit DatabaseEngine.ForceCheckpoint call (page cache backpressure or user-initiated).

Periodic = 0

Periodic timer wake (CheckpointIntervalMs elapsed).

Shutdown = 2

Shutdown — final checkpoint before process exit.