Limitations

Keep these limitations in mind when designing your EdgeWorker functions.

Limitations

These limitations apply to all EdgeWorker functions regardless of the selected resource tier.


Description	Limit
Supported delivery products	Ion Dynamic Site Accelerator (DSA) Adaptive Media Delivery Download Delivery Object Delivery API Acceleration
Supported delivery network	Enhanced TLS Note: When you've applied a custom certificate to a property configuration, the associated Edge hostname uses the `.edgekey.net` domain. Note: Standard TLS, used to serve non PCI compliant traffic over HTTP or HTTPS via an edgesuite.net edge hostname, is not supported. Note: EdgeWorkers is not supported on Akamai CDNs created to accommodate unique regional or governmental requirements. This limitation currently includes China CDN.
Number of activated EdgeWorker scripts per account	5000 per network
Number of EdgeWorker scripts executed per request	1
Compressed size for a code bundle	512 KB
Uncompressed size for a code bundle	1 MB
Maximum response body size for an HTTP sub-request	4000 bytes
Edge constructed HTTP response body size Tip: Edge constructed response bodies are created without making a request to an origin server to fetch content.	2048 characters Note: This limitation only applies to the respondWith() method.
Maximum size of a response body when using the json() and text() methods from the HttpResponse Object	2048 characters for edge constructed response bodies 128 KB for buffered response bodies Unbounded for streamed response bodies
JavaScript initialization timeout Note: The JavaScript initialization time does not include the time it takes to fetch and decompress the EdgeWorkers code bundle.	100 milliseconds
JavaScript CPU initialization timeout	30 milliseconds

Resource tier limitations

These limitations are unique for each resource tier. There are currently two resource tiers available, Dynamic Compute and Basic Compute. Go to the resource tiers section for more informaton including details about which use cases are supported for each resource tier.

Tip: The limits for EdgeWorker IDs created before resource tiers were available will not change. By default, these EdgeWorker functions will execute using Dynamic Compute. The Dynamic Compute limits are the same as the limits applied prior to the introduction of resource tiers.


Event handler	Description	Basic Compute	Dynamic Compute
all event handlers	Maximum CPU time during initialization	30 milliseconds	30 milliseconds
all event handlers	Maximum wall time during initialization	100 milliseconds	100 milliseconds
onClientRequest onOriginRequest onOriginResponse onClientResponse	Maximum memory usage per event handler	1.5 MB	1.5 MB
	Maximum CPU time per event handler	4 milliseconds	10 milliseconds
	Maximum wall time per event handler	100 milliseconds	4 seconds
	Maximum number of HTTP sub-requests allowed from a parent request Note: You can use content fetched using the onClientRequest event handler to modify the original end-user's request cache key. For cache keys modified in this way, you need to use purge by CP Code and not by URL. For instructions on how to purge a CP code see Purge Content by CP code. For instructions on how to create a CP code see Create a CP code.	0	1
	Maximum number of HTTP sub-requests allowed in parallel per request	0	1
	Maximum wall time per HTTP sub-request	0	1 second
	Maximum response size per HTTP sub-request	0	5 MB
responseProvider	Maximum memory usage for responseProvider	2 MB	2 MB
	Maximum CPU time for responseProvider	4 milliseconds	100 milliseconds
	Maximum wall time for responseProvider	100 milliseconds	4 seconds
	Maximum number of HTTP sub-requests allowed for responseProvider	0	50
	Maximum number of HTTP sub-requests allowed in parallel for responseProvider	0	5
	Maximum wall time per HTTP sub-request during the execution of the responseProvider event handler	1 second	1 second
	Maximum response size per HTTP sub-request during the execution of the responseProvider event handler	1 MB	5 MB

Event handler methods

View the supported methods for each of the EdgeWorkers event handlers.


Event handler	Supported methods	Unsupported methods
onOriginRequest onOriginResponse onClientResponse	GET HEAD POST PUT DELETE	CONNECT OPTIONS TRACE PATCH
onClientRequest	GET HEAD OPTIONS	POST PUT DELETE CONNECT TRACE PATCH
responseProvider	GET HEAD	POST PUT DELETE CONNECT OPTIONS TRACE PATCH