OpenPuzzle 1.0.17

OpenPuzzle 1.0.17

OpenPuzzle 1.0.17 hardens process identity across reboot, power loss and
Linux PID reuse.

Persistent process identity now includes the system boot

Linux process identifiers are reused over time. A PID stored before a reboot
can therefore later refer to an unrelated process.

OpenPuzzle now persists the Linux system boot_id together with execution
process state. A stored process is considered potentially active only when:

• the stored boot_id exists;
• the current system boot_id can be read;
• both boot identifiers match; and
• the stored PID still exists.

If any identity check fails, the persisted PID is not trusted.

Safe handling of legacy state

OpenPuzzle 1.0.16 and earlier did not persist a boot identifier.

Legacy execution state and PID-only runtime markers are therefore handled
conservatively. OpenPuzzle does not treat a numerically live PID as proof that
the old execution still exists.

This prevents an unrelated process that happens to reuse the same PID from
being mistaken for OpenPuzzle work.

Runtime-control markers are boot-bound

The persistent runtime markers used by CPU, GPU, CUDA and OpenCL slots now
store both the runtime PID and the current boot_id.

Runtime discovery, safe-stop requests and direct stop requests validate both
values before acting on the stored PID.

A stale marker from a previous boot can be removed safely without signalling
the unrelated process that may now own that PID.

Engine supervisors are boot-bound

Background execution workspaces now persist a process.boot_id alongside
process.pid.

The background launcher reads the current system boot identity before starting
the supervisor. If boot identity cannot be determined, the execution is not
launched.

Execution monitoring and ExecutionStopper require the workspace boot
identity to match the current boot before treating the supervisor as active or
sending signals to its process or process group.

Recovery, updates and heartbeat use the same identity rules

Persistent PID checks are protected consistently across:

• interrupted-execution recovery;
• explicit execution stopping;
• runtime-control state;
• background supervisor monitoring;
• guarded update detection;
• client heartbeat status reporting.

This prevents a reboot followed by PID reuse from causing OpenPuzzle to report
an unrelated process as an active assignment or to signal it accidentally.

Direct signals to subprocesses created with fork() by the current running
OpenPuzzle process remain unchanged because those PIDs are not recovered from
persistent state.

Compatibility and fairness

Normal successful execution, failure reporting, interrupted-assignment
recovery and concurrent CUDA/OpenCL operation remain unchanged.

Assignment fairness is unchanged. Process identity has no effect on priority,
reputation, scheduling rights or access to work.

Validation

OpenPuzzle 1.0.17 passed all 88 automated tests.

Additional process-identity coverage verifies:

• persisted execution state round-trips its boot_id;
• a live numeric PID with a mismatched boot identity is rejected;
• legacy execution state without boot_id fails closed;
• stale runtime PID markers cannot signal a reused process;
• runtime markers persist the current system boot identity;
• workspace supervisors persist and validate process.boot_id;
• the execution monitor does not treat a reused PID from another boot as
  running;
• the execution stopper refuses to signal a process whose workspace boot
  identity does not match;
• heartbeat reporting ignores stale or legacy PID-only execution state;
• update safety checks require matching boot identity before reporting a
  persisted execution as active.

The complete automated suite remains at 88 passing tests.