An instance has one or more application nodes. An application node is a Tomcat web server with a database. When users log in, they end up on one of the available application nodes.
An application node or node contains semaphores, which are a throttling concept. Essentially, semaphores execute and process transactions within an application node. ServiceNow has several semaphores to handle different transactions, like API transactions, default pool transactions (user interaction within the platform, and more.
This article covers how to reallocate semaphore capacity from other semaphores to the API_INT semaphore to process REST API requests faster. This requires an admin user with security_admin to update the ACL. Perform the following:
Under Requires Role, add the admin role. Update or Save the ACL.
To reallocate semaphores to API_INT, login and navigate to "sys_semaphore_set".
In the Semaphore ID column, group by “Semaphore ID”. Add the column for Max Concurrency.
Semaphores can now be reallocated from the Default and Presence pools to API_INT.