If you have a busy project, and the database server is located on a separate physical machine from the application, I recommend that you enable data compression between the application and the database.
The picture shows a clear example of the network load curve. Until 18:00, compression was disabled, at 18:00 - enabled.

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The CPU graph is as follows:

On
mysqlperformanceblog, a benchmark is described using the example of Sphinx.
In PHP, using
mysql_connect is enabled with the "MYSQL_CLIENT_COMPRESS" flag.