Deleting and regenerating cache

Caching is a very important aspect in Oracle WebCenter Sites and nearly all projects depend mostly on strong project design and optimal caching strategy (Note: Caching strategy also considers how your pages are coded). There is no use in going through various caching levels as they are aptly discussed in official document and in Oracle A-Team articles.

Before going through this post, I highly recommend to read about caching and different caches used within WebCenter Sites. This post is more helpful to those people who usually deal with resolving cache related issues.

What I want to highlight in this post is:
1. How to purge all cache?
2. How to re-generate all cache after all cache are purged?

One would ask why to delete all cache?
One of the important task while troubleshooting performance of a webpages is to calculate the number of cache objects generated, then by removing all the cache, hit a certain page(s) and find number of cache objects and dependencies generated for that/those page(s) using Support Tools or Admin UI. This task should generally carried out in Test environment or JSK. Thus, when it required to troubleshoot performance of webpages for full site(s), one can know by number of cache object generated for page(s) by flushing all the cache, make the changes within template or update cache settings and then re-generate all cache objects by hitting all the webpage urls.

How to purge all cache?
To purge all cache, one needs to know what kind of cache is enabled within your project i.e. incache (ehcache) or traditional cache (Only one of them is enabled). Incache is enabled by default within WebCenter Sites installation. Only old version of Oracle WebCenter Sites a.k.a FatWire 7.6 and before uses traditional cache but also has option to enable incache.

For deleting incache where WebCenter Sites is installed - Login to WebCenter Sites > Admin UI > Admin Tab > Expand System Tools Node > Cache Management > double click on Summary tab under CS Cache and Co-Res SS Cache separately. Select all checkboxs for flush cache and click "Flush Cache"
For deleting incache from Remote Satellite Server (RSS) - You can perform the same above step but using the following url:
http://[host]:[port]/[context]/Inventory?username=SatelliteServer&password=[password]

For deleting traditional cache, hit the following url:
http://[ip]:[port]/[context]/CacheServer?all=true&authusername=fwadmin&authpassword=[password]

One can use Support Tools to delete cache.

Furthermore, if you want to delete all incache forcefully, then you can find the location where cs-cache, ss-cache and linked-cache are stored from cs-cache.xml, ss-cache.xml and linked-cache.xml files respectively, which are located under [webapps]/cs/WEB-INF/classes folder and then delete everything under the respective folders. This task is to be performed after WebCenter Sites is shutdown.

How to re-generate all cache after all cache are purged?
Deleting cache is easy task but major problem is generating cache. A website can have hundreds to thousands of webpages and it is very arduous task to hit each webpage url one by one to generate cache. Also, WebCenter Sites does not provide any tool which can crawl through all the page urls. But there are various sites or tools available online which can do the task of crawling of all the webpages. One of the tools which I use and like is flem firefox add-on. It has ability to intake urls from clipboard memory and crawl through them as slideshow. It also has settings to set page load time interval and is very easy to use.

For using flex firefox add-on, basically one would need to first list down all webpage urls of site(s) and just copy & paste to flem add-on and run the slideshow.
If vanity url is configured for a site, then it is very easy to list all urls using the following query:
SELECT 'http://[ip]:[port]/[context]/' || webroot || '/' || webreferenceurl FROM WebReferences

Disclaimer: The code and/or the configurations posted are not official recommendations and should be used at sole's discretion with proper testing before deploying on live WebCenter Sites systems. Cheers!!