Sitecore Caching

Question

could you please explain what's happening here, i see this entries in my log file but i am unable to make out what's happening.

Thanks Hardeep

9160 13:18:33 INFO  Cache created: 'master[data]' (max size: 30MB, running total: 82MB)
9160 13:18:33 INFO  Cache created: 'master[items]' (max size: 20MB, running total: 102MB)
9160 13:18:33 INFO  Cache created: 'master[paths]' (max size: 1MB, running total: 103MB)
9160 13:18:33 INFO  Cache created: 'master[standardValues]' (max size: 1MB, running total: 104MB)
9160 13:18:33 INFO  Cache created: 'web[data]' (max size: 30MB, running total: 134MB)
9160 13:18:33 INFO  Cache created: 'web[items]' (max size: 20MB, running total: 154MB)
9160 13:18:33 INFO  Cache created: 'web[paths]' (max size: 1MB, running total: 155MB)
9160 13:18:33 INFO  Cache created: 'web[standardValues]' (max size: 1MB, running total: 156MB)
9160 13:18:33 INFO  Cache created: 'filesystem[data]' (max size: 0 bytes, running total: 156MB)
9160 13:18:33 INFO  Cache created: 'filesystem[items]' (max size: 0 bytes, running total: 156MB)
9160 13:18:33 INFO  Cache created: 'filesystem[paths]' (max size: 0 bytes, running total: 156MB)
9160 13:18:33 INFO  Cache created: 'filesystem[standardValues]' (max size: 0 bytes, running total: 156MB)

Answer 1

These cache entries are being created from entries in the web.config file. There are four separate areas that define these settings and allow you to specify the settings based on different scopes. For example by database, by site or even globally. The four sections are:

• configuration/sitecore/databases/database
• configuration/sitecore/sites/site
• configuration/sitecore/cacheSizes/sites/website
• configuration/sitecore/settings

The values allow you to scale up or down the amount of memory you use to match the environment you're working in. You can view the usage by browsing to the local url (as stated in an earlier answer) http:///sitecore/admin/cache.aspx. You'll need admin credentials to login to view it. If you find that to be too plain I've also got a modified version that you can use in place of that page here: marketplace.sitecore.net/en/Modules/Caching_Manager.aspx.

The cache entries are stored in groups by use. There are at least eight that you can configure that I'm aware of but that's not all that get created. The configurable ones are:

data - fields items - recently queried items paths - recently queried item paths standardValues - standard values items html - sublayout html registry - sitecore settings like user settings viewState - system templates xsl - xsl control html

The settings in the log you're seeing, 'master[data]' (max size: 30MB, running total: 82MB), are saying that for the "master" database there was a cache named "data" created and it has a maximum capacity of 30MB. I'm unsure about what the running total so I won't speculate.

Answer 2

Basically it's telling you that Sitecore has created a cache. Which means that we reserve a bit of memory to store database data into it. So we can deliver this data extremely quick back to you.

Hope this helps.

Answer 3

Since it was noted that my comment on an answer was better than the answer itself:

These lines are noting that Sitecore is creating caches, as Alex notes.

The usual question is what the max size and running total items mean.

In this particular case our first line is

9160 13:18:33 INFO  Cache created: 'master[data]' (max size: 30MB, running total: 82MB)

At this point the data cache for the master database is being created. The maximum size of that cache is 30MB, and the total memory 'reserved' for all caches until this point is 82MB.

It makes a little more sense when you look at the first three lines.

9160 13:18:33 INFO  Cache created: 'master[data]' (max size: 30MB, running total: 82MB)
9160 13:18:33 INFO  Cache created: 'master[items]' (max size: 20MB, running total: 102MB)
9160 13:18:33 INFO  Cache created: 'master[paths]' (max size: 1MB, running total: 103MB)

Here we see three caches for the master database. When master[items] is added we add 20MB to the previous running total of 82MB to get 102MB. Add 1MB for master[paths] and you get 103MB.

Section 3.4 of the Sitecore 6.6 caching documentation (PDF) (which is approximately the version that was in use when this question was asked, and is still basically relevant, at least through 7.5.x) can help with setting these values and understanding what each cache stores.

Answer 4

Try accessing the cache for your website to get a better idea.

http://yourwebsite.com/sitecore/admin/cache.aspx. It gives you the cache size for a bunch of items.