Document Java Backpressure Option (#9539)

* document java backpressure option

* disable instead of enable

* Apply suggestions from code review

Co-authored-by: Liza Mock <[email protected]>

* address pr review feedback

* Update docs/platforms/java/common/configuration/options.mdx

Co-authored-by: Lukas Bloder <[email protected]>

---------

Co-authored-by: Liza Mock <[email protected]>
Co-authored-by: Lukas Bloder <[email protected]>

Author: 3 people

docs/platforms/java/common/configuration/options.mdx

@@ -162,6 +162,14 @@ _(New in version 6.0.0)_
 
 </ConfigKey>
 
+<ConfigKey name="enable-backpressure-handling">
+
+Set this boolean to `false` to disable automatic downsampling of transactions while the system is under load. The `tracesSampleRate` is halved for every failing health check up to 10 times, (roughly 0.001% of the original `tracesSampleRate`). Any positive health check will reset `tracesSampleRate` to its original value. Health checks run in the background every 10 seconds, checking for queue drops and rate limiting. Note: Starting with version 7.8.0 backpressure handling has changed from opt-in to opt-out.
+
+_(New in version 7.1.0)_
+
+</ConfigKey>
+
 ## Integration Configuration
 
 For many platform SDKs integrations can be configured alongside it. On some platforms that happen as part of the `init()` call, in some others, different patterns apply.

docs/platforms/java/common/configuration/sampling.mdx

@@ -29,6 +29,8 @@ We recommend sampling your transactions for two reasons:
 
 Choose a sampling rate with the goal of finding a balance between performance and volume concerns with data accuracy. You don't want to collect _too_ much data, but you want to collect sufficient data from which to draw meaningful conclusions. If you’re not sure what rate to choose, start with a low value and gradually increase it as you learn more about your traffic patterns and volume.
 
+As of version 7.8.0 of the Java SDK Sentry will automatically downsample while the system is under load. Take a look at <PlatformLink to="/configuration/options/#enable-backpressure-handling"><PlatformIdentifier name="enable-backpressure-handling" /></PlatformLink> for more details or if you would like to opt out of this behaviour.
+
 ## Configuring the Transaction Sample Rate
 
 The Sentry SDKs have two configuration options to control the volume of transactions sent to Sentry, allowing you to take a representative sample: