VM Container Monitor
Use
You can use this monitor to check the utilization of the VM Container, to identify bottlenecks, and to investigate errors. For an introduction to the SAP spool system see the documentation, SAP Virtual Machine Container.
Features
In the monitoring infrastructure, there are various subtrees for monitoring the VM Container. These are integrated in this monitor:
For each instance of the system there are the VMC subtree - VMC General, Java Virtual Machine, Client Requests, Application Cache and Shared Garbage Collector.
You can get further details on each node by choosing Properties.
Choose F1 help on each node to get detailed information.
Subtree VMC General
Here you can find general information on the VM Container and on the resources it uses (memory areas, VM pool, and so on.)
The following table provides information about the monitoring tree elements (MTEs) of this subtree:
MTE Name (MTE Class) |
Meaning (Details in long text for F1 help) |
Status (vmcStatus) |
VMC status - active or inactive |
Shared Pool Size (vmcMemory) |
Size of the shared pool (shared memory for all VMs) |
Shared Memory Usage (vmcSharedMemUsage) |
Size of the memory used from shared pool |
Shared Memory Fragmentation (vmcMemFragment) |
Total fragmentation of the shared memory |
Shared Memory Classes (vmcMemForSharedClasses) |
Memory consumed by shared classes as a percentage of the entire shared pool |
Shared Classes Fragmentation (vmcMemFragmentClasses) |
Fragmentation of the memory area for shared classes |
Shared Memory Closures (vmcMemForSharedClosures) |
Memory consumed by shared closures as a percentage of the entire shared pool |
Shared Closures Fragmentation (vmcMemFragmentClosures) |
Fragmentation of the memory area for shared closures |
Shared code Cache (vmcSharedCodeCache) |
Memory size of the shared code cache |
Shared Code Cache Usage (vmcMemForSharedCodeCache) |
Memory consumed by shared code cache |
No. Free VMs (vmcAvailableVms) |
Number of available VMs |
No. Pooled VMs (vmcNoOfPooledVms) |
Number of VMs in the VM pool |
Sticky VMs (vmcPartStickyVms) |
Number of VMs in "sticky" mode (fixed assignment to a user context based on high memory requriement) |
No. VM Errors (vmcErrors) |
Cumulated number of VM errors |
More Information
● Shared pool, shared classes, shared closures, and so on: Memory Management in the VM Container
● VM Properties: VM Overview
Subtree Java Virtual Machines
This monitor provides details of the running effectiveness and stability of all active VMs.
Some of the values are averages, some are maximum or minimum values, and others are totals. For more information see F1 help on the individual nodes.
The subtree VM Operation provides information about the monitoring tree elements (MTEs):
MTE Name (MTE Class) |
Meaning (Details in long text for F1 help) |
Java Heap Size (vmcJavaHeap) |
Size of the Java Heap for each VM |
CPU Usage (vmcCPUUsageVM) |
CPU used by all active VMs as a percentage |
CPU Usage GC (vmcCPUUsageGCVM) |
Average effective CPU usage for the garbage collection of the VMs as a percentage |
Memory Usage (vmcMemoryUsageVM) |
Average memory consumption of each VM |
Max. Memory Usage (vmcMaxMemoryUsageVM) |
Maximum memory consumption of each VM |
Avg. Full GC Rate (vmcAvgFullGCRateVM) |
Average frequency of full GCs of all VMs |
Max. Full GC Rate (vmcMaxFullGCRateVM) |
Maximum frequency of full GCs of individual VMs |
Avg. GC Rate (vmcAvgGCRateVM) |
Average frequency of GC runs for all VMs |
Max. GC Rate (vmcMaxGCRateVM) |
Maximum rate of GC runs for individual VMs |
No. GC Page Faults (vmcPageFaultRateGC) |
Rate of failed attempts to read the GC memory |
Mem. Availability (single VM) (vmcMaxGCWaterLevelVM) |
Memory availability for individual VMs |
Average Memory Availability (vmcAvgGCWaterLevel) |
Average memory availability for all VMs |
More Information
Memory Management in the VM Container
...
How the Local Garbage Collector Works
Subtree Application Cache
The VM Container cache is a cache for all Java objects.
MTE Name (MTE Class) |
Meaning (Details in long text for F1 help) |
Max. Size (vmcCacheSize) |
Current size of the application cache |
Access Rate (vmcCacheAccessRate) |
Frequency of accesses to cache |
Success Rate (vmcCacheSuccessRate) |
Frequency of successful accesses to cache |
No. Sync. Evictions (vmcSyncEvictionNo) |
Number of deleted old cache entries when adding new entries |
Size Sync. Evictions (vmcSyncEvictionSize) |
Size of deleted old cache entries when adding new entries |
No. Async. Evictions (vmcAsyncEvictionNo) |
Number of deleted old cache entries in the background |
Size Async. Evictions (vmcAsncEvictionSize) |
Size of deleted old cache entries in the background |
More Information
Subtree Shared Garbage Collection
The shared garbage collector (SGC) removes objects no longer needed from the shared pool (shared closures).
MTE Name (MTE Class) |
Meaning (Details in long text for F1 help) |
Max. Water Level (vmcMaxSharedGCWaterLevel) |
Maximum relative occupancy of shared pool by shared GC. |
Avg. Water Level (vmcAvgSharedGCWaterLevel) |
Average relative occupancy of shared pool by shared GC. |
Shared Memory Availability (vmcSharedMemoryAvailable) |
Memory availability in the shared pool |
Shared GC rate (vmcSharedGCRate) |
Frequency of the shared garbage collector runs |
Shared GC Duration (vmcSharedGCDuration) |
Total duration of specified shared GCs |
CPU Usage Shared GC (vmcCPUUsage) |
CPU usage for all specified shared GCs |
Avg. Reclaimed Memory (vmcShGCMemoryReclaimed) |
Average size of released memory for each shared GC (in kB) |
More Information
How the Shared Garbage Collector Works
Memory Management in the VM Container
Subtree Client Requests
The node RFC Container contains the following subtrees.
MTE Name (MTE Class) |
Meaning (Details in long text for F1 help) |
State (vmcRFCContainerState) |
Container status |
RFC Request Rate (vmcRFCRequestRate) |
Frequency of client requests |
Response Time (vmcRFCProcessingTime) |
Average processing time of each client request |
Activities
To start the monitor, follow the procedure below:
1. Start the Alert Monitor using transaction RZ20 or choose CCMS → Control/Monitoring → Alert Monitor.
2. On the CCMS Monitor Sets screen, expand the SAP CCMS Monitor Templates set.
3. Start the VM Container monitor from the list by double-clicking it.