Sample formulas
Sample 1 - Active Memory Utilization
The following is an example of a simple calculation using metrics from a single entity.
This sample formula is created using MEM_ACTIVE and TOTAL_REAL_MEM to obtain Active Memory Utilization.
Field | Value |
|---|---|
Target Entity Category | System |
Target Entity Type | Not selected |
Input Metrics from Target Entity |
|
MEM_ACTIVE statistic | Default |
Additional input metrics | No |
Formula Label | Active Memory Utilization |
Formula Name | F_ACTIVE_MEMORY_UTILIZATION_C |
Formula Result Type | Percentage counter |
Select unit | existing: BYTES |
Formula | Target.MEM_ACTIVE/Target.TOTAL_REAL_MEM |
Calculation:
Target.MEM_ACTIVE = 12.5 GB
Target.TOTAL_REAL_MEM = 64 GB
Active_Memory Utilization = (12.5 / 64.0) * 100.0 = 0.1953
Sample 2 - Spec Rating Used
The following is an example of a formula that is calculated using metrics from an entity and its parent entity.
This sample formula is created using CPU_UTIL and BYBENCHMARK_VALUE to obtain Spec Rating Used.
Field | Value |
|---|---|
Target Entity Category | System |
Target Entity Type | Virtual Machine - KVM |
Input Metrics from Target Entity | [CPU_UTIL] CPU Utilization % |
CPU_UTIL statistic | Default |
Additional input metrics | From parent system |
Parent Entity Type | Virtual Host - KVM |
Input metrics from Parent Entity | [BYBENCHMARK_VALUE] Benchmark value |
BYBENCHMARK_VALUE subresource | SPECINTRATE2006 |
Formula Label | Spec Rating Used |
Formula Name | F_2_C |
Formula Result Type | A count of events, absolute number |
Select unit | existing: Rating |
Formula | Target.CPU_UTIL*Parent.BYBENCHMARK_VALUE |
Calculation:
Target.CPU_UTIL = 25%
Parent.BYBENCHMARK_VALUE = 276
Spec Rating Used = 0.25 * 276.0 = 69
Sample 3 - Memory Over-commit Ratio
The following is an example of a formula that is calculated using metrics from an entity and its child entity. To see how you can use it an analysis, see Using-a-custom-formula-in-an-analysis.
This sample formula is created using TOTAL_REAL_MEM to obtain Memory Over-commit Ratio.
Field | Value |
|---|---|
Target Entity Category | System |
Target Entity Type | Virtual Cluster - VMware |
Input Metrics from Target Entity | [TOTAL_REAL_MEM] Real memory |
Additional input metrics | From child system |
Child Entity Type | Virtual Machine - VMware |
Input metrics from Child Entity | [TOTAL_REAL_MEM] Real memory |
Formula Label | Memory Over-commit Ratio |
Formula Name | F_MEMORY_OVERCOMMIT_RATIO__C |
Formula Result Type | A count of events, absolute number |
Select unit | existing: Ratio |
Formula | SUM(Child.TOTAL_REAL_MEM)/Target.TOTAL_REAL_MEM) |
Calculation:
Target.TOTAL_REAL_MEM = 64GB
Assume 12 VMs each configured with 8 GB memory
SUM(Child.TOTAL_REAL_MEM) = 96 GB
Memory Over-Commit Ratio = 96/64 = 1.5
Sample 4 - Read/Write Ratio
The following is an example of a formula that is calculated using each of the subresources (BY metrics) from the entity.
This sample formula is created using BYDISK_READ_RATE and BYDISK_WRITE_RATE to obtain Read/Write Ratio.
Field | Value |
|---|---|
Target Entity Category | System |
Target Entity Type | Virtual Host - VMware |
Input Metrics from Target Entity |
|
BYDISK_READ_RATE statistic | Default |
BYDISK_WRITE_RATE statistic | Default |
Additional input metrics | No |
Formula Label | Disk RW Ratio |
Formula Name | F_DISK_RW_RATIO1_C |
Formula Result Type | A count of events, absolute number |
Select unit | existing: C |
Formula | Target.BYDISK_READ_RATE/Target.BYDISK_WRITE_RATE |
Calculation:
It is assumed that there are three disks connected to the host. The Read/Write ratio will be calculated for each of the three disks and three charts will be plotted in the analysis.
Disk | Metrics | Disk RW Ratio |
|---|---|---|
d0 | Target.BYDISK_READ_RATE = 1.5 Target.BYDISK_WRITE_RATE = 2.2 | 1.5 / 2.2 = 0.68 |
d1 | Target.BYDISK_READ_RATE = 4.5 Target.BYDISK_WRITE_RATE = 4.45 | 4.5 / 4.45 = 1.011 |
d2 | Target.BYDISK_READ_RATE = 3.5 Target.BYDISK_WRITE_RATE = 0.78 | 3.5 / 0.78 = 4.48 |
Sample 5 - Maximum Network In/Out Byte Rate
The following is an example of a formula that is calculated using each of the subresources (BY metrics) from the entity.
This sample formula is created using BYIF_IN_BYTE_RATE and BYIF_OUT_BYTE_RATE to obtain Maximum Network In/Out Byte Rate.
Field | Value |
|---|---|
Target Entity Category | System |
Target Entity Type | Generic |
Input Metrics from Target Entity |
|
BYIF_IN_BYTE_RATE statistic | Default |
BYIF_OUT_BYTE_RATE statistic | Default |
Additional input metrics | No |
Formula Label | Maximum Network In/Out Byte Rate |
Formula Name | F_MAXIMUM_NETWORK_INOUT_BYTE_RATE_C |
Formula Result Type | A count of events, absolute number |
Select unit | not specified |
Formula | MAXBY(Target.BYIF_IN_BYTE_RATE + Target.BYIF_OUT_BYTE_RATE) |
Calculation:
It is assumed that there are three network interfaces connected to the host. The sum of in and out byte rate will be calculated for each of the three network interfaces, and the maximum value will be plotted in the analysis.
Network Interface | Metrics | Disk RW Ratio |
|---|---|---|
n0 | Target. BYIF_IN_BYTE_RATE = 1.5 Target. BYIF_OUT_BYTE_RATE = 2.2 | 1.5 + 2.2 = 3.7 |
n1 | Target. BYIF_IN_BYTE_RATE = 4.5 Target. BYIF_OUT_BYTE_RATE = 4.45 | 4.5 + 4.45 = 8.95 |
n2 | Target.BYDISK_READ_RATE = 3.5 Target.BYDISK_WRITE_RATE = 0.78 | 3.5 + 0.78 = 4.28 |
For this sample, the value for network interface n1, 8.95, will be plotted.