What do you need to know about Drupal caching?

What do you need to know about Drupal caching?

It is recommended that block and page caching be enabled. Instead of Drupal dynamically performing complex SQL queries it caches these for quick retrieval. If you enabled caching, remember, you may need to Flush Cache (Clear all caches button) to see any changes made to your site.

How is Memcached used to improve Drupal performance?

Memcached allows you to allocate memory where you have more than you need and make it accessible to areas where you have less than you need. When implemented with Drupal, Memcached can store the result of your database query’s in the memory for a specified time, reducing database traffic.

Which is the best http acceleration for Drupal?

HTTP acceleration, or Web Server (Proxy) Caching, will significantly reduce resource requirements and page load times. Varnish Cache, is a widely-used HTTP accelerator for Drupal sites. HTTP acceleration is handled by a reverse proxy.

Is there a caching add on for PHP?

PHP out of the box is a dynamic language and can lead to heavy CPU usage on web servers. There are multiple types of opcode caching add-ons for PHP available that will convert your .php page into memory (byte code) to provide a major benefit in load time and reduced CPU usage.

How to clear the theme cache in Drupal?

To clear a non-Drupal cache, please refer to the procedures for those caches. About clearing the theme cache. The most convenient way to rebuild Drupal’s cache is by using Drush. Running update.php ( http://example.com/update.php) is another way of clearing the cache.

How long does Drupal cache last at max age?

It determines what value Drupal delivers in its max-age header, which is how long the reverse-proxy layer will retain a cache. Performance is often a trade-off between how fresh your content is, and how fast you want to deliver it to the internet. A good value to start with is 15 minutes, but this is something to consider.

How to clear Drupal cache in phpMyAdmin?

In phpMyAdmin, if you would like to clear cache_* tables, select the desired tables and choose “Truncate” from the “with selected” drop-down menu at the bottom of the page. For the command line, see here: The module Devel makes it easy to clear Drupal’s cache.

What is the function db _ QUERY in Drupal?

function db_query. Executes an arbitrary query string against the active database. Use this function for SELECT queries if it is just a simple query string. If the caller or other modules need to change the query, use db_select() instead.

What are the most common SELECT queries in Drupal?

The most common SELECT queries in Drupal are static queries using the query() method of a database connection object. Static queries are passed to the database nearly verbatim.

When to clear or rebuild caches in Drupal?

It is a good practice to clear or rebuild caches when moving a site from one host to another. Clearing the caches can also be useful when installing new modules or themes, and as a first step in troubleshooting. During development it is necessary to clear the cache very frequently. Clearing caches is relatively harmless.

Is there a PHP curl extension for Drupal 7?

The PHP cURL extension is required for the SimpleTest module in Drupal 7 and 8, as well as Aggregator and some contributed modules. Many Linux distributions and development stacks will have it enabled by default, but if your system doesn’t, here are instructions on how to enable it for various platforms are below.

What does cache Max age mean in Drupal?

Cache max-age: Cache controls how long an item may be cached by a number of seconds. 0 means cacheable for zero seconds, i.e. not cacheable. \\Drupal\\Core\\Cache\\Cache::PERMANENT means cacheable forever, i.e. this will only ever be invalidated due to cache tags. (In other words: ∞, or infinite seconds.)

What are the different types of traffic in Drupal?

Drupal is comprised of many layers that all come together, many of which are outside of the software itself. There are two main types of traffic that Drupal can receive, each with very distinct performance attributes. Authenticated Users generally see pages that are dynamic and unique to them.

How can I Make my Drupal website faster?

To create a page Drupal needs to make several database queries. This can slow down websites with a lot of traffic. To make websites faster Drupal stores web pages in a cache. It is a good practice to clear or rebuild caches when moving a site from one host to another.

What’s the Max cache time in Drupal 8?

Max-age: Indicates the maximum time in seconds for which the content can be cached before it must-revalidate. This replaces the Expires header for modern browsing. This option takes its value in seconds with a maximum valid freshness time of one year (31536000 seconds).

How is the Expires header used in Drupal?

Expires: The Expires header sets a time in the future when the content will expire. This header is probably best used only as a fallback. Etag: It is a unique hash identifier of the cacheable object that the browser caches. Whenever a cached response is requested repeatedly, browser checks with the server if the eTag of the response is modified.

How to remove the cache form in Drupal?

To remove the contents of cache_ tables, use phpMyAdmin or another tool to access the desired tables and TRUNCATE (empty, not remove) them. All tables that start with cache_ can safely be truncated EXCEPT the cache_form table.

Why is cache metadata important in Drupal 8?

This is critical for page render times by reducing the number of HTTP requests and reducing the amount of data transferred. Drupal 8 introduced a cache metadata system that allows internal and external caches to be cleared in very granular fashion as data is changed.

How do you clear a file in Drupal?

Create a file named clear.php with the code below. Place the file in the Drupal base directory and run it by browsing to http:. The Drupal cache API can be used to clear specific items. Caching back ends can be switched (to memcache, to flat files, etc.) without having to rewrite any code.