500 Overload Error


PSPDFKit Server has been deprecated and replaced by PSPDFKit Document Engine. All PSPDFKit Server and PSPDFKit for Web Server-Backed licenses will work as before and be supported until 15 May 2024 (we will contact you about license migration). To start using Document Engine, refer to the migration guide. With Document Engine, you’ll have access to robust new capabilities (read the blog for more information).

PSPDFKit Server handles API requests with pooling and queueing. Because every software system has limits in resources, such as memory, PSPDFKit Server has a back-pressure mechanism built in to provide a stable system. When the queue is full, the server will respond with an error to the API request: 500 overload. This mechanism ensures that the server stays reliable, and these errors have to be handled by the clients calling the API by throttling the API requests and retrying failed requests.