Durable Objects

cloudflare Coordination servicecloudflare-durable-objects

Named single-threaded objects that serialise access to their own SQLite storage.

Provider: cloudflare
Kind: Coordination service
Category: Operations
Official docs: https://developers.cloudflare.com/durable-objects/platform/limits/

Properties · 3 set by this component

property	type	values	required	kind default	this component
consensus	enum	none \| raft \| paxos \| zab	no	none	▸ none
managed	boolean	—	no	false	▸ true
maxStorageGb · component property	integer	—	no	10	inherited
nodes	integer	—	no	—	inherited
replicated	boolean	—	no	false	inherited
requestsPerSecondSoftLimit · component property	integer	—	no	1000	inherited
role	enum	metadata \| lock \| discovery \| placement \| sharding \| leader-election \| config	yes	—	▸ lock
singleThreaded · component property	boolean	—	no	true	inherited
storageBackend · component property	enum	sqlite \| key-value	no	sqlite	inherited

Rules that apply · 2

Every rule whose selector covers this component's kind or its category. Whether a rule fires depends on the design: its properties, its edges and its groups.

Shared dependency without redundancyerror

shared-dependency-without-redundancy

The design requires redundant discovery, but this DNS or coordination service, which everything depends on, runs on a single provider or a single replica. Its failure is the whole system's failure.

— all of these hold:
— the design requirement `availability.discoveryRedundant` is true
— any of these hold:
— the node's `redundantProviders` is false
— the node's `replicated` is false

Stateful engine pinned to a single zoneerror

stateful-engine-pinned-to-single-zone

A matching engine, coordination service or event store living in exactly one availability zone, with no failover and no replication, is lost with that zone. Everything that depends on it stops with it.

— all of these hold:
— the node sits inside exactly 1 availability-zone group
— any of these hold:
— the node's `failover` is "none"
— the node's `replicated` is false
— the node's `replication` is "none"

Use it in a design

nodes:
  - { id: "durable-objects", component: "cloudflare-durable-objects" }

Other Coordination service products · 17

Source

1# yaml-language-server: $schema=../../schema/component.schema.json
2# Durable Objects: named single-threaded objects that serialise access to their own storage, used as
3# the coordination and locking primitive of the Workers platform. "Durable Objects - Limits" states
4# new namespaces use the SQLite backend, each object is single-threaded, with 10 GB and ~1,000 rps.
5schemaVersion: "1"
6type: "component"
7id: "cloudflare-durable-objects"
8kind: "coordination-service"
9provider: "cloudflare"
10docs: "https://developers.cloudflare.com/durable-objects/platform/limits/"
11defaults:
12  managed: true
13  role: "lock"
14  consensus: "none"
15properties:
16  storageBackend:
17    type: "enum"
18    values: ["sqlite", "key-value"]
19    default: "sqlite"
20  singleThreaded:
21    type: "boolean"
22    default: true
23  maxStorageGb:
24    type: "integer"
25    default: 10
26  requestsPerSecondSoftLimit:
27    type: "integer"
28    default: 1000

The same page as markdown, for an agent: /catalogue/components/cloudflare-durable-objects.md