Caching data can help you speed up the download site while reducing the load on the primary database server. There are three options for global settings Joomla to control caching. In this article we will tell you about the general principle of the mechanism of caching and cite a few significant examples, which are designed to choose the optimum time of life cache.
- The principle of the mechanism of caching
In the first claim to material or module, immediately going on the preservation of all data, which you have chosen specific files, which are mostly in the directory cache. Such an arrangement can guarantee you that the file names will never be able to cross with existing ones. In addition, that the contents of these files include Cached objects, there also contains additional information about this unique zakenirovannom facility. The next time, the manager checks whether there is such a facility with the same parameters. For example, name, site content, the date of the document and data modification. If this is not found, the material is either changed or has not occurred yet keshirovku. If you request an object and it does not exist in the cache, whereas before showing the user of these data, they will be placed in the cache. But if such Cached data already exist, the program checks the date, time of creation. If the date and time of creation will vary over a wide range longer than the lifetime of the cache, the object will Cached again.
The advantages of long-caching
Found that the cache lifetime is approximately 900 seconds or 15 minutes. It follows that, even without changes to your site, it is still every 15 minutes, the cache will be to recreate anew. Consequently, will be established and unnecessary requests to the database. Manager of the cache can increase the life of the cache only when more of his life. This will help reduce all requests to the database that are not necessary. Many experts believe that the best time in life cache is being updated site. For example, if you add the news about 1 times a day, you spent hours on the process of adding, whereas the life of the cache in the CMS Joomla can be extended to 23 hours.
- Deficiencies long cache
We already told you that with the help of mambotov in CMS Joomla, you can perform many of the manipulation of the text, while not making any real changes in the text. You can allocate any words or terms in the text, replace the reference in the documents do not available snippets of text. Let's say you run a cache, but time ustavleno more, then you are installing a new boat, you can simply did not notice the changes. This happens because the Joomla cease to display the old data, which are in the cache. If any change occurs peregeneratsiya object cache for a particular object, not even including the time the cache, the changes will be displayed correctly. But the modules with the same operation can you lied a little, because the cache after dropping obnulyaet their options. Specialists believe that for sites that use the modules, the information should be updated at 80 - 90% of the total additions news. This is most frequently used in the newsflash, displaynews and others.
Let's summarize the outcome, all of the above. We learned that caching allows you to reduce the load on the database server, it is also a positive effect on the speed of the site to users. Before determine cache lifetime, you must take into account the frequency of updating the material on your site. Also, try not to forget that the termination of cache settings may lead to a cache of material site, but to prokeshirovat modules is to go into the settings menu editing modules and put option Enable cache at the DA.
