AEM Site 404 performance issue

Question

I had ran a load test for 404 response on a 8 core 16GB AEM publish instance. The request urls are something like https://www.myhost.com/content/abc/${__Random(1,1000000)}/,and the response is set in /apps/sling/servlet/errorhandler/404.jsp: <% response.setStatus(404); response.setContentType("text/html"); response.getWriter().write("

Not Found

The requested URL was not found on this server.

"); %> AEM can handle about 700 requests/second, which seems quite low for this simple scenario. Does anybody konw how to improve the 404 throughtout for AEM instance?

Mohit_KBansal · Accepted Answer

Understood. I recommend the following in such a scenario:

Make sure to apply recommended best practices to the publisher [1] [2] [3]
Configure DDoS Protection [4] on CDN, this will block any attempt of attack on the server.
Continuously scan your publisher logs, to find common 404 patterns and add these patterns to the dispatcher's farm filter or CDN.

[1] https://experienceleague.adobe.com/docs/experience-manager-65/deploying/configuring/performance-guid...

[2] https://experienceleague.adobe.com/docs/experience-manager-65/deploying/practices/best-practices-for...

[3] https://blogs.perficient.com/2020/02/19/website-performance-with-the-adobe-experience-cloud/

[4] https://aws.amazon.com/shield/ddos-attack-protection/

Mohit_KBansal · Answer

This is a strange scenario where you are trying to measure the performance of the server by putting a load of 404 requests. In such case, the dispatcher/CDN cache can not be leveraged and requests will always reach to the publisher.

Ideally, in the case of 404, the publisher should do only resource resolution, and return a very lightweight 404 response. Your code seems to be doing the same.

Next, you need to make sure to apply best practices [1] [2] [3] to improve the performance of publisher servers.

I also suggest finding common URL patterns, which are hitting publishers with 404 response code and adding such patterns in your dispatcher farm filter or CDN filter to avoid unwanted load on publishers.

[1] https://experienceleague.adobe.com/docs/experience-manager-65/deploying/configuring/performance-guidelines.html?lang=en

[2] https://experienceleague.adobe.com/docs/experience-manager-65/deploying/practices/best-practices-for-performance-testing.html?lang=en

[3] https://blogs.perficient.com/2020/02/19/website-performance-with-the-adobe-experience-cloud/