Overview
Everblack Grackle provides distributed synchronisation primitives:
- read/write locks
- semaphores
- wait groups (for fan-in or merge)
Grackle state is durable (on disk). All holds have a configurable expiration time. Process crash will not cause a dangling lock. Long-running processes can extend the hold. All operations are atomic and safe to retry.
Grackle is Open Source (under AGPL-3 license). It is also available as a fully managed service at Everblack Cloud. The only difference between OSS and Cloud versions is that there are more advanced APIs to manage API keys and fine-grained permissions in the cloud.