Can a single App Engine Standard Java 11/17 web process handle multiple concurrent requests?

[William Linna]

Hello,

I'm using App Engine Standard with Java 11. My app is packaged as a JAR and it doesn't use legacy bundled services. I have set manual scaling to 1. Now my question is can that one instance handle multiple concurrent requests? According to the documentation, it seems like it cannot.

https://cloud.google.com/appengine/docs/standard/java-gen2/how-requests-are-handled

• By default, each web server processes only one request at a time. To dispatch multiple requests to each web server in parallel, mark your application as threadsafe by adding a <threadsafe>true</threadsafe> element to your appengine-web.xml file.

However, that appengine-web.xml only appears in examples with legacy bundled services. I haven't seen any documentation on how to set up appengine-web.xml for JAR-packaged apps, only for WAR-packaged apps. manual_scaling doesn't allow setting max_concurrent_requests either. app.yaml doesn't support threadsafe-setting.

This is different from envs such as PHP and Go where docs explicitly state that "An instance can handle multiple requests concurrently.".

What should I do? I can't use multiple instances, because I depend on a little bit of state, which is what manual scaling is supposed to afford me.

• Instances remain in memory and state is preserved across requests.

[Andrés Márquez]

YAML config and appengine-web.xml file support max_concurrent_requests setting in Java 11/17.[1][2]

[1] https://cloud.google.com/appengine/docs/standard/java-gen2/config/appref#max_concurrent_requests
[2] https://cloud.google.com/appengine/docs/standard/java-gen2/config/appref-xml#automatic_scaling_max_concurrent_requests

[William Linna]

Thanks for the people who responded.

It seems that the documentation has been fixed, and no longer states that each web server processes only one request at a time etc.

I no longer need help with this issue