sentry-php: Ignored exceptions are still built

I have a microservice that calls an external API. Sometimes, this external API will timeout, and my application will create a GatewayTimeoutException, with a NoResponseException as previous exception, with a Http\Client\Exception\NetworkException as previous exception, with a GuzzleHttp\Exception\ConnectException. It’s 4 level deep.

I found that a lot of time was spent handling those in Sentry, so I added them to the list of ignored exceptions. This did not result in an improvement, because it seems the exceptions are still handled by Sentry, even if they are ultimately not sent to the server. I mitigated the issue by not setting the NoResponseException as a previous exception when not in debug mode, it resulted in a 100ms improvement. I won’t share the blackfire trace because I can’t redact things in it, but here is a screenshot of the interesting part, which does not involve code in my application:

Using

sentry/sdk                          2.1.0   This is a metapackage shipping sentry/sentry with a recommended http client.
sentry/sentry                       2.3.2   A PHP SDK for Sentry (http://sentry.io)
sentry/sentry-symfony               3.5.1   Symfony integration for Sentry (http://getsentry.com)