Cache metrics

Insights into an application’s utilization of the VIP Platform’s caching layers can be reviewed in the Insights & Metrics panel, located in the application view of the VIP Dashboard.

Select the tab labeled “Cache” to access metrics for cache utilization by an environment.

It is important that a WordPress or Node.js application is utilizing the caching layers as efficiently as possible even during normal windows of time so that it is more likely to scale smoothly and quickly during a high traffic event.

Page Cache Hit Rate

VIP’s page cache is the first layer of caching encountered by each request made to a WordPress or Node.js environment.

The data in “Page Cache Hit Rate” indicates the rate of change in the page cache hit rate over time for an environment. The page cache hit rate represents the percentage of attempts to fetch data from the page cache where the data is successfully retrieved.

A low cache hit rate is likely to result in more requests being made to the origin server which can negatively affect application performance.

Object Cache Hit Rate

All WordPress environments and qualifying Node.js environments

The WordPress object cache is the second layer of caching encountered by requests to a WordPress environment that pass through the page cache and are routed to the origin servers.

The data in “Object Cache Hit Rate” indicates the percentage of object cache requests where the requested data was successfully retrieved, without needing to retrieve it directly from the database.

A drop in cache hit rate for the environment’s object cache are indicated by the Object Cache Hit Rate Anomaly Event Type in the “Object Cache Hit Rate” panel.

The object cache panel in Query Monitor can be used to investigate and improve the efficiency of the use of the object cache by an application.

Object Cache Queries by Type

All WordPress environments and qualifying Node.js environments

The data in “Object Cache Queries by Type” indicates the number of object cache queries that are being made by the PHP application, grouped by query type (i.e. Get, Set, Delete). High query counts can indicate inefficient queries or a high number of requests being made to the application.