Depending on PHP Sentry client version,

Sentry client v1 (Raven_Client) you can configure the client in different send modes (curl_method), sync (default), async (curl_multi), exec (fork)

https://docs.sentry.io/clients/php/config/

For Sentry client v2 I think you need to configure the Transport layer to use async

https://docs.sentry.io/platforms/php/configuration/transport...