---
title: "Performance VMware Host System Alarms"
slug: "performance-vmware-host-system-alarms"
description: "See what each Performance: VMware Host System alarm in a SysTrack role monitors, with the factory limits, times, and on or off state."
status: "update"
updated: 2026-10-26T15:14:24Z
published: 2026-10-26T15:14:24Z
canonical: "documentation.lakesidesoftware.com/performance-vmware-host-system-alarms"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://documentation.lakesidesoftware.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Performance VMware Host System Alarms

The Performance: VMware Host System alarms monitor the CPU, memory, disk, network, and power use of a VMware host. This article lists each alarm with what it monitors and its factory defaults.

The **Performance: VMware Host System** category is on the **Alarms** tab of a role (**Configure** > **System Configuration** > **Roles**). To turn these alarms on and change their limits, times, and profiles, see [Configure Alarms in a Role](/documentation/docs/configure-alarms-in-a-role).

In the example alarm configuration called out below, if CPU Percent usage is 90% or higher for 120 seconds a **Yellow** level alarm is triggered. If CPU usage is 95% or higher for 240 seconds a **Red** level alarm is triggered.

![](https://cdn.document360.io/87d11426-6b1f-4b19-b593-b71e55a81af3/Images/Documentation/image(500).png?sv=2026-02-06&spr=https&st=2026-11-08T17%3A12%3A36Z&se=2026-11-08T18%3A12%3A36Z&sr=c&sp=r&sig=nAuHmiuaAPk9R24HxnFjAgrb9KrRpcPl2FkszEMI0Dc%3D)

## Performance VMware Host System Alarms and Defaults

The **Default** column shows the factory values. A role can change them.

| Alarm | Description | Default |
| --- | --- | --- |
| CPU Core Utilization (%) | Checks the host server CPU core consumption. This is indicative of the level of demand placed on the system by the virtual machines (VMs) that it hosts. | Off. Yellow 90 for 120 s, Red 95 for 240 s. |
| CPU Co-Stop (ms) | Monitors the amount of time a symmetric multiprocessing (SMP) virtual machine was ready to run, but was delayed due to co-CPU scheduling contention. | Off. Yellow 1500 for 120 s, Red 3000 for 240 s. |
| CPU Idle | Monitors the time that the CPUs of the host are idle. | Off. Yellow 4000000 for 120 s, Red 8000000 for 240 s. |
| CPU Latency (%) | Checks for the percentage of time virtual machines on the host system are unable to complete processor transactions due to contention over physical CPUs. | Off. Yellow 90 for 120 s, Red 95 for 240 s. |
| CPU MHz | Monitors the CPU usage in megahertz during the interval. | Off. Yellow 0 for 120 s, Red 0 for 240 s. |
| CPU Percent | Monitors the actively used CPU, as a percentage of the total available CPU, for each physical CPU on the host. | Off. Yellow 90 for 120 s, Red 95 for 240 s. |
| CPU Ready (ms) | Checks the time, in milliseconds, that the virtual machine was ready, but could not get scheduled to run on the physical CPU. CPU ready time is dependent on the number of virtual machines on the host and their CPU loads. | Off. Yellow 15000 for 120 s, Red 30000 for 240 s. |
| CPU Swap Wait (ms) | Checks the amount of time in milliseconds the virtual machine is waiting for swap page-ins. CPU Swap Wait is included in CPU Wait. | Off. Yellow 4000000 for 120 s, Red 8000000 for 240 s. |
| CPU Wait (ms) | Checks the total time in milliseconds that a virtual CPU is not runnable. It could be idle (halted) or waiting for an external event such as input/output (I/O). | Off. Yellow 4000000 for 120 s, Red 8000000 for 240 s. |
| Datastore Max Total Latency (ms) | Checks for the highest latency value (in milliseconds) across all datastores used by the host. | Off. Yellow 1500 for 120 s, Red 3000 for 240 s. |
| Disk Average I/O Rate (Hz) | Monitors the aggregated disk I/O rate in kilobytes per second. For hosts, this metric includes the rates for all virtual machines running on the host during the collection interval. | Off. Yellow 1000000 for 120 s, Red 2000000 for 240 s. |
| Disk Bytes Read (kBps) | Monitors the average number of kilobytes per second read from the disk during the collection interval. | Off. Yellow 1000000 for 120 s, Red 2000000 for 240 s. |
| Disk Bytes Written (kBps) | Monitors the average number of kilobytes per second written to disk during the collection interval. | Off. Yellow 1000000 for 120 s, Red 2000000 for 240 s. |
| Disk Max Total Latency (ms) | Checks for the highest latency value (in milliseconds) across all disks used by the host. Latency measures the time taken to process a Small Computer System Interface (SCSI) command issued by the guest OS to the virtual machine. The kernel latency is the time VMkernel takes to process an I/O request. The device latency is the time it takes the hardware to handle the request. | Off. Yellow 1500 for 120 s, Red 3000 for 240 s. |
| Memory Compressed (kB) | Monitors the amount of memory compressed by ESX (in kilobytes). | Off. Yellow 400000 for 120 s, Red 800000 for 240 s. |
| Memory Compression Rate (kBps) | Monitors the memory compression rate (in kilobytes per second). | Off. Yellow 8000 for 120 s, Red 10000 for 240 s. |
| Memory Consumed (kB) | Monitors the amount of machine memory (in kilobytes) used on the host. Consumed memory includes memory used by the VMkernel, vSphere services, plus the total consumed metrics for all running virtual machines. | Off. Yellow 7000000 for 120 s, Red 14000000 for 240 s. |
| Memory Decompression Rate (kBps) | Monitors the memory decompression rate (in kilobytes per second). This rule uses a VMware host side counter. | Off. Yellow 8000 for 120 s, Red 10000 for 240 s. |
| Memory Latency (%) | Monitors the percentage of time virtual machines on the host system are unable to complete memory transactions due to contention. | Off. Yellow 90 for 120 s, Red 95 for 240 s. |
| Memory Swap In Rate (kBps) | Monitors the average rate, in kilobytes per second, at which memory is swapped in from the host cache to active memory. | Off. Yellow 8000 for 120 s, Red 10000 for 240 s. |
| Memory Swap Out Rate (kBps) | Monitors the average rate (in kilobytes per second) at which memory is swapped out to the host swap file. | Off. Yellow 8000 for 120 s, Red 10000 for 240 s. |
| Memory Percent | Monitors the memory usage as percentage of available machine memory. For a host, the percentage is calculated as follows: consumed memory ÷ machine memory size. | Off. Yellow 90 for 120 s, Red 95 for 240 s. |
| Memory Shared (kB) | Monitors the sum of all shared metrics for all powered-on virtual machines, plus amount for vSphere services on the host (in kilobytes). The shared memory of the host may be larger than the amount of machine memory if memory is over committed (the aggregate virtual machine configured memory is much greater than machine memory). The value of this statistic reflects how effective transparent page sharing and memory over commitment are for saving machine memory. | Off. Yellow 3000000 for 120 s, Red 6000000 for 240 s. |
| Memory Shared Common (kB) | Monitors the amount of machine memory that is shared by all powered-on virtual machines and vSphere services on the host (in kilobytes). Subtract this metric from the shared metric to gauge how much machine memory is saved due to sharing (shared - shared common = machine memory (host memory) savings (KB)). | Off. Yellow 400000 for 120 s, Red 800000 for 240 s. |
| Memory State | Checks for one of four threshold levels representing the percentage of free memory on the host. The counter value determines swapping and ballooning behavior for memory reclamation. 0: (high) Free memory >= 6% of machine memory. 1: (soft) 4% 2: (hard) 2% 3: (low) 1% 0 (high) and 1 (soft): Swapping is favored over ballooning. 2 (hard) and 3 (low): Ballooning is favored over swapping. | Off. Yellow 1 for 120 s, Red 2 for 240 s. |
| Memory VM Control (kB) | Monitors the total amount of memory (in kilobytes) allocated by the virtual machine memory control driver (vmmemctl) for all powered-on virtual machines, plus vSphere services on the host. The vmmemctl driver is a VMware exclusive memory-management driver that controls ballooning. It is installed with VMware Tools. | Off. Yellow 2000000 for 120 s, Red 4000000 for 240 s. |
| Net Bytes Received (kBps) | Monitors the average rate (in kilobytes per second) at which data was received across each physical network interface controller (NIC) instance on the host during the interval. This represents the bandwidth of the network. | Off. Yellow 5000000 for 120 s, Red 10000000 for 240 s. |
| Net Bytes Transmitted (kBps) | Monitors the average rate (in kilobytes per second) at which data was transmitted across each physical network interface controller (NIC) instance on the host during the interval. This represents the bandwidth of the network. | Off. Yellow 5000000 for 120 s, Red 10000000 for 240 s. |
| Net Packets Rx | Monitors the number of packets that the host receives across all its network adapters. | Off. Yellow 400000 for 120 s, Red 800000 for 240 s. |
| Net Packets Tx | Monitors the number of packets that the host sends across all its network adapters. | Off. Yellow 300000 for 120 s, Red 600000 for 240 s. |
| Net Percent Usage | Monitors the combined rate at which the host sends and receives data across all its network adapters. | Off. Yellow 30 for 120 s, Red 50 for 240 s. |
| Power (W) | Monitors the power consumption in watts. | Off. Yellow 200 for 120 s, Red 400 for 240 s. |
| Up Time (sec) | Monitors the total time elapsed, in seconds, since last system startup. | Off. Yellow 300 for 120 s, Red 120 for 240 s. |