Remote database -> massive response time increase?

Yes

90-100ms round trip + time to prepare SQL statement + time to execute statement + time to send results back multiplied by the number of times you need to query the database.

Sure the connection may stay open but it’s an inherently expensive thing to do.

Considering that some setups can respond in full in less than 100ms never mind the database connection, you should look into co-locating your database and your server, if not on to the same machine but somewhere very very close.

WordPress specific things that may help include:

  • Object caches
  • Database query caching
  • fewer SQL queries
  • Use of transients to store the results of expensive operations

You can see what SQL queries are made and slow queries using tools such as the query monitor plugin

Related Posts:

  1. Can’t connect to MySQL server on ‘127.0.0.1’ (10061) (2003)
  2. MySQL SELECT increment counter
  3. Failed to connect to mysql at 127.0.0.1:3306 with user root access denied for user ‘root’@’localhost'(using password:YES)
  4. Using wpdb to connect to a separate database
  5. WordPress (MyISAM) database is slow, should I switch to InnoDB?
  6. The MySQL alternatives: Do Percona Server and MariaDB work well with WordPress, and do they make WordPress go better?
  7. WordPress Database lost auto increment
  8. wpdb->insert multiple record at once
  9. Restoring WordPress posts from database only
  10. Slow wp_term_relationships query
  11. How to use “TRUNCATE TABLE” MySQL statement?
  12. Using Dynamic Data Pulled from a MySQL Table in a WordPress Page
  13. WordPress for a very large website
  14. What are conventions about the schema of the $table_prefix
  15. WooCommerce with thousands of products – site is very slow – optimize db queries? [closed]
  16. Migrating non-WordPress CMS to WordPress, lots of data to move — possible solutions?
  17. Is deleting orphaned wp_options entries safe?
  18. How to solve slow WordPress site caused by attachment_metadata
  19. Delete all post meta except featured image
  20. Connect to live db whilst working locally
  21. WooCommerce – Query for ordered products
  22. Large database causes slow load
  23. How to execute mulitple statement SQL queries using $wpdb->query?
  24. Delete duplicate rows from wordpress database where a column is duplicate in phpmyadmin
  25. Database slowdown after update to 3.4.1
  26. Query WordPress database by registered date and role
  27. Tons of Twitter rows in my database
  28. How to insert data into MySQL database from the form created in WordPress site
  29. Set Display Name to first and last name (phpmyadmin SQL Query)
  30. Migrating database / content of non-CMS site to WordPress
  31. Does WordPress ever need multiple databases?
  32. Why are no posts showing despite my apparently correct DB restoration?
  33. Select Multiple meta_value from WP DB; Single Query
  34. Which is more efficient? Using usermeta, or creating a new MySQL table?
  35. Is it possible to split database tables using HyperDB?
  36. What happens if I overwrite the current wp_options table with a backup from a week ago?
  37. SQL Error wp_commentmeta – incorrect table definition
  38. WordPress database error – Error in SQL syntax – I can’t identify any error?
  39. CRUD operations using WordPress database API
  40. How do I get the posts within a certain year/date(with sql query)?
  41. Handling large N data in WordPress
  42. How to Mirror WordPress database from Remote server to Local server
  43. Is MariaDB’s Aria storage engine suitable for WordPress?
  44. Slow queries constantly getting stuck on WordPress database of ~100,000 posts
  45. A MySQL DB within a MySQL DB
  46. How do I query wp_options for expired transient pairs with MySQL commands?
  47. Is there a way to recover the table wp_term_relationships?
  48. Trouble Migrating all data blog from WordPress.com to WordPress.org
  49. WordPress running SQL query to update database from form
  50. How to fix database error duplicate entry
  51. Migration: Copying database content to a different server
  52. Call to undefined function get_user_meta() – trying to access data in MySQL from custom fields
  53. How do I convert a MySQL database from utf8mb4 to utf8 encoding?
  54. Query multiple tables at once?
  55. Have working sql query… trying to adjust it to use $wpdb
  56. Remove empty rows from the database
  57. Custom WordPress Table wpdb
  58. Why this query is not showing any result on wordpresss home page?
  59. Best practice to limit results in get_row()?
  60. Trouble running $wpdb->query() with last_insert_id
  61. how to encyrpt DB_PASSWORD in wp-config
  62. Remote database connection and local development
  63. How can I detect right db type?
  64. Moving WordPress site to new domain – database import [duplicate]
  65. Changing order of db results when encoding to JSON
  66. Second ezSQL initialization for MSSQL
  67. Fetch a single row from a custom table for to a given ID
  68. Database create or redirect
  69. How to escape percentage sign(%) in sql query with $wpdb->prepare?
  70. Link multiple user databases together?
  71. DB prefix not updating
  72. Recovery – Restore Database after moving folder location locally
  73. I wanted to Know that how can I give ingore to 0000-00-00 in my config file
  74. Set a cron job to delete a specific database table table every midnight
  75. How to import products in host instead of database on wordpress?
  76. I would like some help wth an SQL query to link posts with categories
  77. Where is the HTML-handler part in the wpdb class?
  78. How to map data on CSV to web pages?
  79. next comment id number wordpress
  80. insert data from a form:: Warning Empty query mysqli::query()
  81. How can I get $wpdb to show MySQL warnings?
  82. Merging development site with live site
  83. The MySQL Connection could not be established., before it was joomla but i have change it into worpress
  84. WordPress Database Posts Table query
  85. How to extract some part of WordPress full source code
  86. Missing latest posts and options after DB migration via phpMyAdmin
  87. Local Content different from Remote Content
  88. Check if a database is well installed
  89. live site do not update after importing sql database
  90. using same mysql user with many databases
  91. How do i get value from wp_postmeta?
  92. “MySQL server has gone away” since update to 3.8
  93. featured image not showing up with mysql_connect
  94. MySQL Database User: Which Privileges are needed?
  95. Import Excel (or csv) Table with user-data as subscribers to wordpress
  96. Print output of Table Creation
  97. Migrated to Namecheap, now Trouble with Database & wp-config [closed]
  98. SQL query : Select a thumbnail for a media
  99. SQL Query to get post_id from wp_posts and and meta_key(s) from wp_postmeta
  100. How to find fresh (last modified) and sql backup?