Quotas and limits

ClearBlade IoT Core limits resource allocation and use and enforces appropriate quotas on a per-project basis. Specific policies vary depending on resource availability, user profile, service usage history, and other factors and are subject to change without notice.

Limits

This section lists ClearBlade IoT Core’s quotas in project/device/telemetry, rate, and time categories.

Project, device, and telemetry limits

Quota

Limit

Can be increased

Quota

Limit

Can be increased

Devices per project per region

Unlimited, but the default is 100,000

Yes

Device registries per project per region

100

Yes

Devices bound to a gateway

10,000

No

Devices attached to a gateway

1,000

No

Gateways bound to a device

10

No

Device ID length

256 bytes

No

Device registry ID length

256 bytes

No

Device metadata

500 key-value pairs

No

Device metadata key

128 characters

No

Device metadata value

32 KB

No

Combined size of metadata key-value pairs

256 KB

No

Credentials per device

3

No

Configuration versions per device

10

No

Device configuration data

64 KB

No

Maximum page size for list request

500

No

Device state payload

64 KB

No

Telemetry event notification configurations

10

No

Telemetry event payload

256 KB

No

MQTT connections per device

1

No

Open MQTT connections per project per region

10,000

Yes

Active HTTP device connections (within the past 5 minutes) per project per region

10,000

Yes

Rate limits

Quota

Limit

Can be increased

Quota

Limit

Can be increased

HTTP device telemetry publishes per device

6,000 per min

No

Device telemetry publishes per project

Unlimited, but the default is 60,000 per min

Yes

Device-to-cloud throughput per device

512 KB/s

No

Cloud-to-device throughput per device

512 KB/s

No

Configuration updates per device

1 per sec

No

Attribute updates per device

1 per sec

No

Attribute updates per registry

1 per sec

No

Device manager API read calls per project

30,000 per min

Yes

Device manager API create and delete calls per project

3,000 per min

No

Device manager API update calls per project (see the exception in the next row)

3,000 per min

Yes

Device manager API modifyCloudToDeviceConfig calls per project

6,000 per min

Yes

MQTT incoming messages per sec per connection

100 per sec

No

Device MQTT connections per device

1 per sec

No

Device MQTT connections and HTTP requests per project

60,000 per min

Yes

State updates per device

1 per sec*

No

State updates per project

6,000 per min*

Yes

Number of logged events per project

1,000 per sec

Yes

Size of logged events per project

1 MB per sec (each log entry is roughly 1 KB)

Yes

Commands per registry

1,000 per sec

Yes

Commands per project

1,000 per sec

Yes

MQTT subscriptions to the commands topic per device connection

1 per sec

No

*For details, see Getting device state.

Time limits

Quota

Limit

Can be increased

Quota

Limit

Can be increased

JWT authorization clock skew

10 min

No

JWT lifetime (exp minus iat cannot exceed the limit)

24 hr**

No

MQTT idle time (without heartbeat or message)

20 min

No

MQTT connection time

24 hr***

No

Command timeout

60 sec

No

Command retries

60 sec

No

**JWT lifetimes of 6 - 24 hrs are recommended. JWT lifetimes should not be shorter than 30 min.
***Connections may be reset occasionally (for example, for a server restart).

Quota enforcement

Exceeding quota consequences differ for projects and resources, such as registries and devices:

  • Project exceeds quota: The project is blocked until usage is back under the limit. In rare cases, a quota enforcement period can continue even when your usage is no longer over the limit. If your project is still blocked even though you're no longer exceeding any quotas, wait a while and try again.

  • Device using the MQTT bridge exceeds quota: The device is disconnected.

  • Device using the HTTP bridge exceeds quota: The device receives a RESOURCE_EXHAUSTED response.

For example, if you attempt to update a device's configuration more than once per second over the MQTT bridge, ClearBlade IoT Core disconnects the device. To fix the problem, publish device configurations no more than once per second, ideally once per 10 seconds, then reconnect the device. See Configuring devices for more information.

Quota increases

Limits are set at their maximum values by default. To request an increase above the maximum, email iotcore@clearblade.com with this information:

  1. Your name and email

  2. Registry name

  3. Describe your request

  4. Describe which quota to be increased

Compressed HTTP requests

As noted in Using the HTTP bridge, a device can send gzip-compressed data to ClearBlade IoT Core over the HTTP bridge.

Telemetry event and device state payload limits are calculated using each request’s uncompressed size.

For example, if a device sends a compressed 10 KB telemetry event payload, but the original payload before compression was 257 KB, the request fails because 257 KB exceeds the 256 KB telemetry event payload limit.