Warning message at java application startup "OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended"

[ssf65000]

Description

I'm using NewRelic java agent in my java application. On startup I'm getting this log:

OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
2026-04-16T13:13:39,819-0400 [33030 3] com.newrelic INFO: New Relic Agent: Loading configuration file "/xxxxx/newrelic/./newrelic.yml"
2026-04-16T13:13:39,842-0400 [33030 3] com.newrelic INFO: Using default collector host: collector.newrelic.com
2026-04-16T13:13:39,843-0400 [33030 3] com.newrelic INFO: Using default metric ingest URI: https://metric-api.newrelic.com/metric/v1
2026-04-16T13:13:39,843-0400 [33030 3] com.newrelic INFO: Using default event ingest URI: https://insights-collector.newrelic.com/v1/accounts/events
2026-04-16T13:13:39,912-0400 [33030 3] com.newrelic INFO: New Relic Agent: Writing to log file: /xxxxx/newrelic/logs/newrelic_agent.log
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended
OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended

From what I read, this is causing CDS to be partially limited/degraded. 

Expected Behavior

Expected behavior - no warnings, CDS is fully operational

Steps to Reproduce

Add NewRelic java agent to any java application. You'll see multiple "Sharing is only supported for boot loader classes because bootstrap classpath has been appended" warnings

Your Environment

Java: OpenJDK Runtime Environment Corretto-25.0.2.10.1 (build 25.0.2+10-LTS)
OS: MacOS Tahoe 26.3.1
NewRelic java agent : 9.2.0

[Newrelic-Boomi]

https://new-relic.atlassian.net/browse/NR-553148

[jtduffy]

Because of the way the agent operates, it must modify the bootstrap class path on startup, which triggers this message. There's nothing in the agent we can do to suppress this message.