DIspatcher Flush Issue - Stat file creation

[EstebanBustamante]

Hi, 

I am seeing an odd behavior while flushing cache, I am using AEM 6.5.16 with the wknd site for testing, also I am using a dispatcher in a Centos machine and it was set using the default configs from the AEM Project archetype (v41).

So, the statfilelevel is set to 2 by default as shown below:

 /cache {
# The cacheroot must be equal to the document root of the webserver
/docroot "${PUBLISH_DOCROOT}"
# sets the level upto which files named ".stat" will be created in the
# document root of the webserver. when an activation request for some
# handle is received, only files within the same subtree are affected
# by the invalidation.
/statfileslevel "2"

According to this documentation https://experienceleague.adobe.com/docs/experience-manager-learn/ams/dispatcher/disp-flushing.html?l... my expectation would be to have .stat 3 files when a flush event is triggered, like below:

- /var/www/html/.stat  (statfilelevel 0)
- /var/www/html/content/.stat  (statfilelevel 1)
- /var/www/html/content/wknd/.stat (statfilelevel 2)

 But actually, I see in the logs there are only 2 .stat files being created. These files are being touched correctly, if i re-flush the cache, those are being updated correctly (timestamp), so the cache "should" invalidate.

The problem is when I request again a page such as: [/content/wknd/us/en.html], the dispatcher is looking for a .stat file at a deeper level

[/mnt/var/www/html/content/wknd/.stat], which does not exist as explained above, and thus the cache is not invalidated.

So here are my questions:
1) Is really expected that only 2 .stat files should be created when the statfilelevel is set to 2? If not, how can I troubleshoot further? 

2) Even if the file .stat does not exist at the deeper level, was not supposed that the dispatcher should look up the nearest .stat file? Which I understand is the one located at [/content/.stat] level and thus invalidates the whole [/content/wkn] path.

Things that I've tried so far that gave the same result:

- I made sure the dispatcher config is correctly set and restarted the Apache server several times,

- I made sure the directories have the proper write access and I have disabled SELinux security just in case is messing with the folder.

- Flush via CURL command or via ACS Flush Feature, the same result, only 2 files are created

- Increased the statfilelevel to 3, the .stat files are still only 2, what changes is that the dispatcher will look for a .stat file in a deeper level to validate against the previous invalidation process e.g: [/mnt/var/www/html/content/wknd/us/.stat]

Hope someone can provide some hints to understand what's going on. 

Thanks in advance

[rawvarun]

Change the log level to debug.

Also, refer https://experienceleague.adobe.com/docs/experience-manager-dispatcher/using/configuring/dispatcher-c... for dispatcher config.

[EstebanBustamante]

Did you fully read the question? I provided screenshots showing the logs which of course are at debug level.

[rawvarun]

Are you using AMS or AEM as a cloud?

I see the AMS documentation link for the dispatcher mentioned in your question.

[EstebanBustamante]

This is on-premise, not AMS nor AEMaaCS, is there any architectural difference about how the cache is being flushed on the cloud? As per my understanding, the dispatcher module is the same, which under the hood is the one who exposes the /invalidate API for flushing cache, so I am not sure if really the flavor of AEM matters, I may be wrong, If so, I will be happy to review that

[kautuk_sahni]

@EstebanBustamante , were you able to sort this up? If so, I would request you to share the solution with AEM community for posterity. 

[EstebanBustamante · Accepted solution]

Yes, in case someone else is misunderstanding this.

What I miss here was the fact that there is a difference between DELETE and ACTIVATE replication action types. It looks like the .stat files are relevant when using ACTIVATE type because this is targeted for a single resource, in the other case, if I need to flush a whole directory I would use DELETE and won't care about the stats files.

Here is more info about it:

https://adobe-consulting-services.github.io/acs-aem-commons/features/dispatcher-flush-rules/index.ht...