A slow Wordpress website maybe due to a number of reasons.
1. Your package's computing power isn't sufficient for your Wordpress to load quickly.
Some customers are easily tempted to use CLOUD-MINI, UNLI-BASIC or CLOUD-BASIC thinking that it would be sufficient for their needs. Under normal use case, it is true that these packages may be able to host an average Wordpress site. However, let's keep in mind that some Wordpress installation are either relatively complex--one that has a number of plugins that use high amount of memory or one with relatively large contents such as big media files like videos and images and others maybe using a number of complex Javascripts.
UNLI-CLOUD customers who are using Wordpress for complex installations with a considerable number of plugins or when using memory hungry contents are advised to switch to BUSINESS CLOUD packages for higher CPU and RAM resource. It may be possible that you did not review the RAM and CPU allotted for the package before paying for the subscription but you would notice upon careful comparison that packages under BUSINESS CLOUD have higher CPU and RAM resource for the same package tier, i.e. CLOUD-BASIC has about twice RAM and has 1 tier CPU power compared to UNLI-BASIC although both package have the same price. If you wish to shift to BUSINESS CLOUD package with the equivalent tier, please open a ticket to the client area to request for a package upgrade. There’s no additional fee to upgrade from UNLI to BUSINESS CLOUD package in the same tier. If you are already using BUSINESS or ENTERPRISE CLOUD and you still experience slow loading of your website, please open a support ticket inside the client area or send an email to [email protected]
For more details, please read our packages’ uses cases here http://www.zoom.ph/announcements.php?id=16
2. You have faulty plugins, incorrectly configured or outdated plugin or have installed too much unnecessary plugins.
Some customers install a lot of plugins that they would normally try but never use, however, they leave their plugins active or worst, improperly configured. A plugin use up memory and computing power “CPU” as it loads and try to do certain task during load time and this may contribute to extra load time and memory usage. In order to avoid memory leak due to plugins overload, please uninstall unnecessary plugins and make sure the active plugins are correctly configured.
3. Oversized media files
Some novice Wordpress users use oversized image files, i.e. for their website banner, background and even article images. Often, users do not bother to resize the images for optimum page load time. It’s too common that we see customers complaining that their website is loading very slow only to find out that their 5 banner images is 1.5Mbytes in size each and the entire home page is around 10Mb in size. All too often, these customers are connected via home DSL lines, thus loading 10Mb page takes a few minutes.
webpagetest.org may help you diagnose website loading speed and detect scripts or contents that are taking a long time to load.
4. Your Wordpress installation is vulnerable to Trackback, Pingback and Comment Spamming. These spamming strategies often waste a lot of CPU and memory power. Below are some useful links to prevent spamming.
https://codex.wordpress.org/Combating_Comment_Spam/FAQ
http://premium.wpmudev.org/blog/trackback-pingback-spam/
http://www.wpbeginner.com/wp-tutorials/how-to-put-a-stop-to-wordpress-trackback-spam/
5. Your Wordpress installation has security holes that allows hackers to compromise a site or use your website to house spamming scripts.
As a rule of thumb, you must make sure that your site is secured. Below are some useful links about how to harden your Wordpress site.
http://codex.wordpress.org/Hardening_WordPress
http://resources.infosecinstitute.com/hardening-wordpress/
http://premium.wpmudev.org/blog/keeping-wordpress-secure-the-ultimate-guide/
https://blog.sucuri.net/2012/07/wordpress-and-server-hardening-taking-security-to-another-level.html
https://blog.sucuri.net/2012/06/how-to-stop-the-hacker-by-hardening-wordpress.html