High I/O (Input/Output) load shows increased access to your data. I/O load statistics represent all data exchanges between web application running on the Apache server and disk field and RAM memory.
Causes
- Whole website, or its part, experiences very high amount of visitors. Check the attendance of the website or separate web pages, if there aren’t any unusual number. Recommended tool for checking attendance is Google analytics.
- Website may be hacked. Check if there are any unwanted files e.g. comments in the discussions. Check the settings of the .htaccess file. In the attendance statistics look up from which countries the visitors are. If there are any foreign or exotic countries, it may indicate that the website is hacked. Compare your website content with older backups. Change the password as a precaution.
- If your website attendance is legitimate and there is still high I/O load, the PHP application may not be optimized. Check the source code or whether it loads or saves too large amount of files.
- You can ask our technical support for full analysis of the website performance. Our experienced administrators will advice you where the website may be optimized regarding the performance and use of resources.
- Common cause of high I/O load is creation of your own backup of the website . Mostly CMS are creating a backup by default of the website including previously created backups. The size of such backup gets larger each time the backup is created. We recommend to check the backup settings and deselect the directories where the backups are stored. Or you can rely on our backup system that we provide.
How ti decrease I/O load
- Turn on all available forms of caching the content of your website, for more information see our guide. To decrease the I/O load ideally set the caching to memcache.
- Consider the PHP version upgrade to higher newer version and newer database server. If you use standard CMS like WordPress, Joomla or Drupal, we also recommend to upgrade the version to the newest. It may be faster and more importantly any previous safety issues are patched in newest versions.
If even after you check the attendance and source code of the website and the I/O load is still high, the problem may be the operation on the shared architecture. It may threaten the operation of other websites. Therefore we can ask you to move your website to your own VPS server or dedicated physical server.