Operational Limits for Business Central Online

To ensure the availability and quality of Business Central services, there are limits on certain operations. This article describes the limits and, in some cases, the strategy behind them.

Tip

Telemetry is gathered on some of the operations that have a limit. The telemetry provides insight into operations for which limits were exceeded. For more information, see Monitoring and Analyzing Telemetry.

Client connection limits

Setting Description Limit
Reconnect period The time during which a client can reconnect to the service after being disconnected. 10 minutes

Data handling limits

Setting Description Limit
Max items in object graph The maximum number of objects to serialize or deserialize. 10,000
Max file size The maximum size of files that can be uploaded to or downloaded from the service. 350 MB
Maximum stream read size The maximum number of bytes that can be read from a stream (InStream object) in a single AL read operation. Examples include READ or InStream.READTEXT method calls. This setting pertains to UTF-8 and UTF-16 text encoding; not MS-DOS encoding. 1,000,000 bytes

Database limits

Setting Description Value
Search timeout The time (in seconds) that a search operation on lists in the client continues before it's stopped. When the limit is reached, the following message displays in the client: Searching for rows is taking too long. Try to search or filter using different criteria. 10 seconds
SQL command timeout The contextual time-out for a SQL command. 30 minutes
SQL connection idle timeout The time that a SQL connection can remain idle before being closed. 5 minutes
SQL connection timeout The time to wait for the service to connect to the database. When the time is exceeded, the attempt is canceled and an error occurs. This setting also applies to begin, rollback, and commit of transactions. 1.5 minutes
Long running SQL query threshold The amount of time that an SQL query can run before a warning telemetry event occurs. If this threshold is exceeded, the following event is logged: Action completed successfully, but it took longer than the given threshold. 1000 ms

Asynchronous task limits

Setting Description Limit
ChildSessionsMaxConcurrency The maximum number of child sessions that can run concurrently per parent session. When the value is exceeded, additional child sessions will be queued and run when a slot becomes available as other child sessions are finished. 5
ChildSessionsMaxQueueLength The maximum number of child sessions that can be queued per parent session. If the value is exceeded, an error occurs. 100
Maximum concurrent running scheduled tasks The maximum number of tasks that can run simultaneously for an environment.

If there are many jobs running at the same time, you might experience that the response time for clients gets slower. If the value is too low, it might take longer for scheduled tasks to process.
3
MaximumSessionRecursionDepth The maximum number of nested sessions that can be created before reaching infinite recursion. If the limit is exceeded, a runtime error occurs with the message: Excessive recursive session creation detected, original session ID: [id], current session ID: [id]. 14
Page background task default timeout The default amount of time that page background tasks can run before being canceled. Page background tasks can be also given a timeout value when enqueued at runtime. This limit is used when no timeout is provided when the page background task is enqueued. 2 minutes
Page background task max timeout The maximum amount of time that page background tasks can run before being canceled. Page background tasks can be also given a timeout value when enqueued at runtime. If a page background task is enqueued with a timeout greater than this limit, this limit is ignored. 10 minutes

Report limits

Setting Description Limit
Default max documents The maximum number of documents that can be merged in a report using a Word layout. Users can override this setting on a report-basis from the report request page. If exceeded, the report will be canceled.

Developers can override this setting by using MaximumDocumentCount property of a report. Client users can do the same when running a report from the report request page
200
Max documents The maximum number of documents that can be merged in a report using a Word layout. If exceeded, the report will be canceled. 500
Default max execution timeout The maximum execution time that it can take to generate a report by default. Users can override this setting on a report-basis from the report request page. If exceeded, the report will be canceled.

Developers can override this setting by using the ExecutionTimeout property of a report. Client users can do the same when running a report from the report request page.
6 hours
Max execution timeout The maximum execution time that it can take to generate a report. If exceeded, the report will be canceled. 12 hours
Default max rows The maximum number of rows that can be processed in a report by default. Users can override this setting on a report-basis from the report request page. If exceeded, the report will be canceled.

Developers can override this setting by using the MaximumDataSetSize property of a report. Client users can do the same when running a report from the report request page.
500,000
Max rows The maximum number of rows that can be processed in a report. If exceeded, the report will be canceled by the server. 1,000,000

Query limits

Setting Description Limit
Max execution timeout The maximum execution time that it can take to generate a query. If exceeded, the query will be canceled. 30 minutes
Max rows The maximum number of rows that can be processed in a query. If exceeded, the query will be canceled. 1,000,000

OData request limits (per environment)

Setting Description Limit
Max concurrent requests The maximum number of OData V4 requests the server instance can actively process at the same time. Requests that exceed the limit will wait in the queue until a time slot becomes available. 5
Max connections The maximum number of simultaneous OData requests on the server instance, including concurrent and queued requests. When the limit is exceeded, a 429 (Too Many Requests) error occurs. 100
Max page size The maximum number of entities returned per page of OData results. 20,000 entities per page
Max batch size The maximum number of operations in a batch call. 100 operations per batch
Max request queue size The maximum number of pending OData V4 requests waiting to be processed. When the limit is exceeded, a 429 (Too Many Requests) error occurs. 95
Rate The number of OData requests per minute that are allowed. An HTTP response code 429 - Too Many Requests is returned if limits are exceeded. Sandbox:
300 requests/minute

Production
- 600 requests/minute
Operation timeout The maximum amount of time that the service gives a single OData request. When the limit is exceeded, an HTTP response code 408 - Request Timeout is returned.

After 8 minutes, the session is canceled.
8 minutes

SOAP request limits (per environment)

Setting Description Limit
Max concurrent requests The maximum number of SOAP requests the server instance can actively process at the same time. Requests that exceed the limit will wait in the queue until a time slot becomes available. 5
Max connections The maximum number of simultaneous SOAP requests on the server instance, including concurrent and queued requests. When the limit is exceeded, a 429 (Too Many Requests) error occurs. 100
Max message size The maximum permitted size of a SOAP web service requests 65,536 KB
Max request queue size The maximum number of pending SOAP requests waiting to be processed. When the limit is exceeded, a 429 (Too Many Requests) error occurs. 95
Rate Specifies how many SOAP requests per minute are allowed. An HTTP response code 429 - Too Many Requests is returned if limits are exceeded. Sandbox:
300 requests/minute

Production:
600 requests/minute
Operation timeout The maximum amount of time that the service gives to a single SOAP request. When the limit is exceeded, HTTP response code 408 - Request Timeout is returned. 8 minutes

See Also

Working with API Rate Limits
Microsoft API Terms of Use