Thread

Hi, i’ve just discovered tag-caching, which seems amazing, significantly reducing the number of db queries on my pages. However, the docs hardly say anything about it, and particularly they don’t say if the cache is cleared when the data changes (as happens with template caching).

Course, I’ve tested it and this is what seems to happen 😊 but i just want to check for the official answer.

If it’s true, the only reason you wouldn’t have tag caching turned on *everywhere* is if your template loops are time dependent, right?

It may also depend on your host. For instance, you don’t normally need to turn on template caching on EngineHosting.. Yes, the cache is cleared when certain events happen.

Thanks Sue. Is it possible that you could tell us what those events are? It would be really good to be clear on this.

Tag caching means that an entry might not go “live” at the exact specified time, because the tag’s cache hasn’t expired, or might not disappear from the site at once, things like that. A new entry should trigger a cache refresh anyway, however.

This Feature request is related to an previous Support Question:
When is the (channel) cache cleared when the data changes (as happens with template caching).

Sorry to dig up an old thread (google-ing for fine grained cache info).
Ingmar, that’s interesting approach that some entries “might not go live” (future entries) or disappear (expiration time) due to enabling caching. 

Some questions are still standing:
- Which actions do fire a cache flush? 
And i Quote (template caching):
For example, if you cache your comments page, when someone submits a comment, the cache will be cleared
1. how does it determine we’re on a comments-page? Channel comments-page setting? Comments-tag?
2. What are other examples (and determined by what) when the cache will be flushed?
3. What actions cause a channels-tag cache to refresh? Or is that caching ‘only’ time based?

Currently it is a bit of behind the scenes magic, and sadly not very well explained.

(continued here: caching feature request)

Hi GDmac,

I am not sure what you mean by “channel cache”. Is your question regarding tag caching or template caching? The behavior will depend on the cache type. I agree that this should be documented better, as well.

Referring to the channel:entries cache=“yes” refresh=“60”
What (edit/publish or other?) actions cause the cache to refresh? Or is it ‘only’ time based?

Hi, GDmac. let me ask the dev team. 😊 Thanks in advance for your patience.

Any news on this?

Hi GDMac,

It’s my understanding that the Template Cache clears itself when new comments or new Channel Entries are added to the system. I’d like to get you a better explanation from the devs, however, so let me ask one of them. I’m sorry your question was forgotten before, but I can promise we’ll get back to you this time!

Hi GDmac,

Here is my compiled list of actions that clears your caching

Some only happen if the config is set to clear cache on new entry ($config[‘new_posts_clear_caches’] = ‘y’;)

* Comments have a few exceptions and intricacies

- Deleting a Category Group (clears all cache)
- Updating or creating a Category (clears relationship cache)
- Ordering categories (clears database cache)
- Updating, creating or deleting a Category Custom Field (clears all cache)

- Deleting a Field Group (clears all cache)
- Updating, creating or deleting a Custom Field (clears all cache)

- Deleting a Status Group (clears all cache)

- Updating Multi Entries (clears if needed either all or sql cache)
- Updating Multi Categories (clears if needed either all or sql cache)

- Deleting Watermark Preferences (clears db cache)
- Updating or Deleting Upload Preferences (clears db cache)

- Updating or creating a Snippet (clears all cache)
- Updating or creating a Global Variable (clears all cache)

- Updating a Template (clears all cache)
- Creating a Template from File (clears db cache)

- Updating an Email Notification (clears all cache)
- Updating a Theme Template (clears all cache)
- Running a Template Sync (clears all cache)

- Submission, updating or deleting of an Entry through API (clears if needed either all or sql cache)

- Creating, updating or deleting a Comment (clears all cache *)
- Change Comment Status (clears all cache)
- Comment Preview (clears all cache *)

- Publish or Edit Metaweblog Post (clears if needed either all or sql cache)
- Set Metaweblog Post Category (clears if needed either all or sql cache)

- Checking Moblog (clears if needed either all or sql cache)

- Create or Update Simple Commerce item (clears page cache)

- Deleting files from Wiki (clears db cache)
- Update Wiki Template (clears all cache)
- Editing Wiki Article (clears db cache)
- Opening or closing a Wiki Revision (clears db cache)

GDMac, was John Henry’s list helpful for you?

I don’t know if helped GDMac, but helped me!

Why this list isn’t on user guide? Could somebody put this list there? Please!

Hi Robson,

I agree that the docs could be improved with that information and as such I’ve filed a bug report for you on this issue.

Great info on the cache stuff from John Henry and I’ll add my vote for this being added to the docs.