Memory

The Memory window shows counters that provide information about the garbage collector.

The Memory window shows the followings counters :

Garbage collections /sec
induced: number of times (per second) a garbage collection was performed because of an explicit call to GC.Collect. Its a good practice to let the GC tune the frequency of its collections.
Gen0:number of times (per second) the generation 0 objects (youngest; most recently allocated) are garbage collected (Gen 0 GC) since the start of the application. Gen 0 GC occurs when the available memory in generation 0 is not sufficient to satisfy an allocation request. This counter is incremented at the end of a Gen 0 GC. Higher generation GCs include all lower generation GCs. This counter is explicitly incremented when a higher generation (Gen 1 or Gen 2) GC occurs. _Global_ counter value is not accurate and should be ignored. This counter displays the last observed value.
Gen1:number of times the generation 1 objects are garbage collected since the start of the application. The counter is incremented at the end of a Gen 1 GC. Higher generation GCs include all lower generation GCs. This counter is explicitly incremented when a higher generation (Gen 2) GC occurs. _Global_ counter value is not accurate and should be ignored. This counter displays the last observed value.
Gen2:number of times the generation 2 objects (older) are garbage collected since the start of the application. The counter is incremented at the end of a Gen 2 GC (also called full GC). _Global_ counter value is not accurate and should be ignored. This counter displays the last observed value.
%Time in Garbage Collections
% Time in GC: percentage of elapsed time that was spent in performing a garbage collection (GC) since the last GC cycle. This counter is usually an indicator of the work done by the Garbage Collector on behalf of the application to collect and compact memory. This counter is updated only at the end of every GC and the counter value reflects the last observed value; its not an average.
Heap Size (MBytes)
All heaps: sum of four other counters; Gen 0 Heap Size; Gen 1 Heap Size; Gen 2 Heap Size and the Large Object Heap Size. This counter indicates the current memory allocated in bytes on the GC Heaps.
Gen0: maximum Mbytes that can be allocated in generation 0 (Gen 0); its does not indicate the current number of Mbytes allocated in Gen 0. A Gen 0 GC is triggered when the allocations since the last GC exceed this size. The Gen 0 size is tuned by the Garbage Collector and can change during the execution of the application. At the end of a Gen 0 collection the size of the Gen 0 heap is infact 0 bytes; this counter displays the size (in bytes) of allocations that would trigger the next Gen 0 GC. This counter is updated at the end of a GC; its not updated on every allocation.
Gen1: current number of Mbytes in generation 1 (Gen 1); this counter does not display the maximum size of Gen 1. Objects are not directly allocated in this generation; they are promoted from previous Gen 0 GCs. This counter is updated at the end of a GC; its not updated on every allocation.
Gen2: current number of Mbytes in generation 2 (Gen 2). Objects are not directly allocated in this generation; they are promoted from Gen 1 during previous Gen 1 GCs. This counter is updated at the end of a GC; its not updated on every allocation.
Large Objects:current size of the Large Object Heap in Mbytes. Objects greater than 20 KBytes are treated as large objects by the Garbage Collector and are directly allocated in a special heap; they are not promoted through the generations. This counter is updated at the end of a GC; its not updated on every allocation.
Commited and Reserved virtual memory (MBytes)
Commited: amount of virtual memory (in Mbytes) currently committed by the Garbage Collector. (Committed memory is the physical memory for which space has been reserved on the disk paging file).
Reserved: amount of virtual memory (in Mbytes) currently reserved by the Garbage Collector. (Reserved memory is the virtual memory space reserved for the application but no disk or main memory pages have been used.)
Promoted and Promoted Finalization Memory (Bytes/sec)
Promoted Memory Gen 0: bytes of memory that survive garbage collection (GC) and are promoted from generation 0 to generation 1; objects that are promoted just because they are waiting to be finalized are not included in this counter. This counter displays the value observed at the end of the last GC; its not a cumulative counter.
Promoted Memory Gen 1: bytes of memory that survive garbage collection (GC) and are promoted from generation 1 to generation 2; objects that are promoted just because they are waiting to be finalized are not included in this counter. This counter displays the value observed at the end of the last GC; its not a cumulative counter. This counter is reset to 0 if the last GC was a Gen 0 GC only.
Promoted Finalization Memory Gen 0: bytes of memory that are promoted from generation 0 to generation 1 just because they are waiting to be finalized. This counter displays the value observed at the end of the last GC; its not a cumulative counter.
Promoted Finalization Memory Gen 1: bytes of memory that are promoted from generation 1 to generation 2 just because they are waiting to be finalized. This counter displays the value observed at the end of the last GC; its not a cumulative counter. This counter is reset to 0 if the last GC was a Gen 0 GC only.
Number of Pinned Objects Pinned: number of pinned objects encountered in the last GC. This counter tracks the pinned objects only in the heaps that were garbage collected e.g. a Gen 0 GC would cause enumeration of pinned objects in the generation 0 heap only. A pinned object is one that the Garbage Collector cannot move in memory.
Number of Finalization Survivors Survivors: number of garbage collected objects that survive a collection because they are waiting to be finalized. If these objects hold references to other objects then those objects also survive but are not counted by this counter; the "Promoted Finalization-Memory from Gen 0" and "Promoted Finalization-Memory from Gen 1" counters represent all the memory that survived due to finalization. This counter is not a cumulative counter; its updated at the end of every GC with count of the survivors during that particular GC only. This counter was designed to indicate the extra overhead that the application might incur because of finalization.
Number of Sink Blocks in use Sink blocks: current number of sync blocks in use. Sync blocks are per-object data structures allocated for storing synchronization information. Sync blocks hold weak references to managed objects and need to be scanned by the Garbage Collector. Sync blocks are not limited to storing synchronization information and can also store COM interop metadata. This counter was designed to indicate performance problems with heavy use of synchronization primitives.

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