ACTool-Config-Worker may throw an exception because it executes very expensive queries, preventing startup

[thomasmueller]

The following two queries are executed at startup (thread name "Apache Sling Repository Startup Thread #1-ACTool-Config-Worker"). Depending on the content, they may try to read more than 100'000 nodes, which throws an exception, and so startup fails.

SELECT ace.* FROM [rep:ACE] AS ace 
WHERE ace.[rep:principalName] IS NOT NULL 
AND ISDESCENDANTNODE(ace, [/content])

SELECT ace.* FROM [rep:ACE] AS ace 
WHERE ace.[rep:principalName] IS NOT NULL 
AND ISDESCENDANTNODE(ace, [/apps])

Specially the first query may read too many entries. Both queries use the index /oak:index/acPrincipalName.

I think this is somewhat related to #219 - however switching to a Lucene index won't resolve the issue.

• In general, at startup, queries should not read that many nodes. If they do, startup can be delayed too much. I would recommend to run expensive queries (if they are really needed) after startup, so that startup is not blocked. Until the query is run, a cache can be used.
• Queries should no try to read more than about 5000 nodes. If they need to read more, then keyset pagination should be used, see also https://jackrabbit.apache.org/oak/docs/query/query-engine.html#keyset-pagination

[ghenzler]

@thomasmueller Is the problem happening during image build or during startup of k8s pod?

Overall the following should be true:

• During image build, the AC Tool will run the config against the whole repo. However then the repo should not have more than 5000 ACE nodes (mostly OOTB ACEs in /libs folder from ootb AEM packages)
• During pod startup, the AC Tool will run the config against the repo without paths /apps and /libs. It normally does this async if not configured differently (maybe that is the problem in your case)

You can check the the following code to see what is happening here:

accesscontroltool/accesscontroltool-startuphook-bundle/src/main/java/biz/netcentric/cq/tools/actool/startuphook/impl/AcToolStartupHookServiceImpl.java

Line 68 in 43e00e4

public void activate(BundleContext bundleContext, Config config) {

and you can check for the respective log messages in your setup.

[thomasmueller]

Hi,

Thanks a lot! The problem I see, it is run at AEM startup of k8s (author), against the whole repository (including /content). This is in the Repository Startup thread; it is blocking the startup.

It normally does this [async]

Great! So maybe the case I saw had a non-default configuration! How can this be configured? It then might just be a matter of explaining this; possibly improving the documentation.

[kwin]

It then might just be a matter of explaining this; possibly improving the documentation.

This OSGi configuration is not documented at all, so hopefully no one deviates from the default without knowing exactly what to do here:

accesscontroltool/accesscontroltool-startuphook-bundle/src/main/java/biz/netcentric/cq/tools/actool/startuphook/impl/AcToolStartupHookServiceImpl.java

Line 56 in 039f56a

boolean runAsyncForMutableConent() default true;

[kwin]

The issue seems to be the evolution of the AEMaaCS build pipeline as outlined in https://adapt.to/2023/schedule/evolution-of-the-aemaacs-build-pipeline.

1. The build image step does no longer involve custom code
2. During the deploy step the composite node store seems to be used in seed mode (i.e. the method

   accesscontroltool/accesscontroltool-bundle/src/main/java/biz/netcentric/cq/tools/actool/helper/runtime/RuntimeHelper.java

   Line 20 in 039f56a

   public static boolean isCompositeNodeStore(Session session) {

   will never return true in AEMaaCS.