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-Xthr

Syntax

    -Xthr:<parameter>

Parameters

AdaptSpin | noAdaptSpin

    -Xthr:AdaptSpin
    -Xthr:noAdaptSpin
This tuning option is available to test whether performance optimizations are negatively impacting an application.

fastNotify | noFastNotify

    -Xthr:fastNotify
    -Xthr:noFastNotify
When a large number of threads try to acquire a Java™ monitor, throughput of an application can be reduced. This issue is known as high contention. If high contention occurs when the Java wait and notify features are regularly used, you can use -Xthr:fastNotify to increase throughput. However, -Xthr:noFastNotify is the default setting, because it is faster in all other scenarios.

cfsYield | noCfsYield (Linux® only)

    -Xthr:cfsYield
    -Xthr:noCfsYield
The default value, cfsYield, enables threading optimizations for running on Linux with the Completely Fair Scheduler (CFS) in the default mode (sched_compat_yield=0). The noCfsYield value disables these threading optimizations. You might want to use the noCfsYield value if your application uses the Thread.yield() method extensively, because otherwise you might see a performance decrease in cases where yielding is not beneficial.

minimizeUserCPU

    -Xthr:minimizeUserCPU
Minimizes user-mode CPU usage in thread synchronization where possible. The reduction in CPU usage might be a trade-off in exchange for decreased performance.

secondarySpinForObjectMonitors | noSecondarySpinForObjectMonitors

    -Xthr:secondarySpinForObjectMonitors
    -Xthr:noSecondarySpinForObjectMonitors
This tuning option is available to test whether performance optimizations are negatively impacting an application.