Cache Page

The Caches page gives an overview of cache performance across all endpoints for currently selected backend projects with summary graphs for Miss Rate and Requests Per Minute (throughput). You can use these as a starting point to see if there are any potential cache performance issues, for example, a higher than expected Miss Rate percentage.

If you see an anomaly or want to investigate a time range further, click and drag to select a range directly in the graph and data will be filtered for that specific time range only.

The transaction table shows a list of endpoints that contain at least one cache.get span along with:

• Its average value size (the bytes being fetched from cache)
• Throughput
• Average transaction duration
• Miss rate percentage (how often did a lookup did not return a value)
• Time spent (total time your application spent on a given transaction)

By default, this table is sorted by most time spent. This means that endpoints at the top are usually really slow, requested very frequently, or both. You can change the sort order to view top transactions by throughput, miss rate percentage, average value size, or average transaction duration.

To investigate a specific endpoint, click on it to open a sidebar showing some sample events and additional duration metrics.

Sample List

To help you compare the performances of cache hits (where a value was found in the cache) versus misses (where no value corresponding to the key was found in the cache) over time, Sentry automatically surfaces a distribution of both samples for the timeframe selected from the Caches page.

These sample events are shown as triangles in the average duration graphs at the top. These sample events are also listed in the table below, along with their spans, key, transaction duration, and hit/miss status.

From the sample list, you can drill down to specific good, average, or bad examples of cache performance within an endpoint. To view the detailed trace that contained the span operation, click on a Span ID.