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src/hotspot/share/prims/jvmti.xml

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rev 52132 : 8201655: Add thread-enabled support for the Heap Sampling
Summary:
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13578           <description>
13579             JNI local reference to the object that was allocated.
13580           </description>
13581       </param>
13582       <param id="object_klass">
13583         <jclass/>
13584           <description>
13585             JNI local reference to the class of the object.
13586           </description>
13587       </param>
13588       <param id="size">
13589         <jlong/>
13590         <description>
13591             Size of the object (in bytes). See <functionlink id="GetObjectSize"/>.
13592         </description>
13593       </param>
13594     </parameters>
13595   </event>
13596 
13597   <event label="Sampled Object Allocation"
13598     id="SampledObjectAlloc" const="JVMTI_EVENT_SAMPLED_OBJECT_ALLOC" num="86" since="11">
13599     <description>
13600       Sent when an allocated object is sampled.
13601       By default, the sampling interval is set to 512KB. The sampling is semi-random to avoid
13602       pattern-based bias and provides an approximate overall average interval over long periods of
13603       sampling.
13604       <p/>
13605       Each thread tracks how many bytes it has allocated since it sent the last event.
13606       When the number of bytes exceeds the sampling interval, it will send another event.
13607       This implies that, on average, one object will be sampled every time a thread has
13608       allocated 512KB bytes since the last sample.
13609       <p/>
13610       Note that the sampler is pseudo-random: it will not sample every 512KB precisely.
13611       The goal of this is to ensure high quality sampling even if allocation is
13612       happening in a fixed pattern (i.e., the same set of objects are being allocated
13613       every 512KB).
13614       <p/>
13615       If another sampling interval is required, the user can call
13616       <functionlink id="SetHeapSamplingInterval"></functionlink> with a strictly positive integer value,
13617       representing the new sampling interval.
13618       <p/>




13578           <description>
13579             JNI local reference to the object that was allocated.
13580           </description>
13581       </param>
13582       <param id="object_klass">
13583         <jclass/>
13584           <description>
13585             JNI local reference to the class of the object.
13586           </description>
13587       </param>
13588       <param id="size">
13589         <jlong/>
13590         <description>
13591             Size of the object (in bytes). See <functionlink id="GetObjectSize"/>.
13592         </description>
13593       </param>
13594     </parameters>
13595   </event>
13596 
13597   <event label="Sampled Object Allocation"
13598     id="SampledObjectAlloc" const="JVMTI_EVENT_SAMPLED_OBJECT_ALLOC" filtered="thread" num="86" since="11">
13599     <description>
13600       Sent when an allocated object is sampled.
13601       By default, the sampling interval is set to 512KB. The sampling is semi-random to avoid
13602       pattern-based bias and provides an approximate overall average interval over long periods of
13603       sampling.
13604       <p/>
13605       Each thread tracks how many bytes it has allocated since it sent the last event.
13606       When the number of bytes exceeds the sampling interval, it will send another event.
13607       This implies that, on average, one object will be sampled every time a thread has
13608       allocated 512KB bytes since the last sample.
13609       <p/>
13610       Note that the sampler is pseudo-random: it will not sample every 512KB precisely.
13611       The goal of this is to ensure high quality sampling even if allocation is
13612       happening in a fixed pattern (i.e., the same set of objects are being allocated
13613       every 512KB).
13614       <p/>
13615       If another sampling interval is required, the user can call
13616       <functionlink id="SetHeapSamplingInterval"></functionlink> with a strictly positive integer value,
13617       representing the new sampling interval.
13618       <p/>


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