[beberlei]

This is due to how PHP and Sentry for PHP works. It sends out the data after every request to Sentry backend via HTTP. Depending on your network path to their servers, I have seen this take 10-100ms. This is different on how other APMs work for PHP, for example Tideways that I work on, or DataDog/NewRelic/Blackfire. They have a local agent running that accepts the data over socket/tcpip before sending it to the backend for processing.

The workaround in case of Sentry is to deploy the Sentry Relay in your network and send all data there.