VMware performance is a top concern for many application administrators when a virtualization initiative begins and can become a quagmire for a virtualization administrator if an issue strikes. While some VM performance issues may occur unexpectedly, such as an unforeseen spike in web traffic that strains disk I/O for a web server, many conditions that can lead to VMware performance issues like upward trending VMware memory utilization can be detected in early stages. Nipping such problems in the bud can be accomplished by implementing a regular VM monitoring process.
For starters, a data center must resolve to take the time to execute a VM monitoring process with regular environment "check-ups". Ideally, a VMware administrator will examine system performance on a daily, weekly, and monthly basis to evaluate trends in capacity availability and usage growth at different intervals:
To undertake the monitoring practices mentioned above, VM administrators should evaluate system metrics for CPU, memory, storage I/O, and storage space usage for all VMs and datastores in an environment. This metrics data is available within VMware’s vCenter and can be exported into Excel or viewed within vCenter in resource usage graphs set at different time scales. More details concerning the metrics to assess, and what values should alert of impending issues are provided in the recently released whitepaper VMware Performance Monitoring to Avoid Slow VMs.
Optimally, through a regular monitoring process, data centers should be able to foresee VM issues that would occur from resource shortages or capacity bottlenecks, and anticipate peak usage overflow for regularly recurring processes such as monthly in-depth virus scan. These insights allow virtualization administrators to preemptively rebalance resource usage loads or add more resources before a VMware performance problem occurs.
The steps described above can be time-consuming and must occur at regular intervals to effectively catch emerging VM performance issues. To automate this VM monitoring process, VKernel’s recently released vOPS Performance Analyzer, collects 20 performance metrics from vCenter every 30 minutes, monitoring resource usage at five minute granularity levels to detect utilization spikes. Additionally, Performance Analyzer allows virtualization administrators to create trending alarms to be warned when a particular resource’s usage has changed by a specified amount in a certain time frame. The end result is that after a 20 minute installation, the processes described above requires no recurring manual intervention. Instead the environment’s health can be assessed on a daily, weekly, and monthly basis from a summary report. Any notable issues can be set to generate immediate alarms.
Stay tuned for the next part of the Maintaining VM Performance blog series where we explore what to do if despite proactive monitoring efforts, a VM performance problem still occurs unexpectedly.