Fling Labs: IOBlazer – IOPS and bytes/s and IO latency and playback VSCSI traces captured on VMware ESX through the vscsiStats utility

Source: Fling Labs

Summary

IOBlazer is a multi-platform storage stack micro-benchmark. IOBlazer runs on Linux, Windows and OSX and it is capable of generating a highly customizable workload. Parameters like IO size and pattern, burstiness (number of outstanding IOs), burst interarrival time, read vs. write mix, buffered vs. direct IO, etc., can be configured independently. IOBlazer is also capable of playing back VSCSI traces captured using vscsiStats. The performance metrics reported are throughput (in terms of both IOPS and bytes/s) and IO latency.

IOBlazer evolved from a minimalist MS SQL Server emulator which focused solely on the IO component of said workload. The original tool had limited capabilities as it was able to generate a very specific workload based on the MS SQL Server IO model (Asynchronous, Un-buffered, Gather/Scatter). IOBlazer has now a far more generic IO model, but two limitations still remain:

  1. The alignment of memory accesses on 4 KB boundaries (i.e., a memory page)
  2. The alignment of disk accesses on 512 B boundaries (i.e., a disk sector).

Both limitations are required by the gather/scatter and un-buffered IO models.

A very useful new feature is the capability to playback VSCSI traces captured on VMware ESX through the vscsiStats utility. This allows IOBlazer to generate a synthetic workload absolutely identical to the disk activity of a Virtual Machine, ensuring 100% experiment repeatability.

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VDSPowerCli From Fling – Powershell for the Distributed Switch

Summary

Note: The functionality of this Fling has now been introduced into a release of PowerCLI. Whenever possible, use the latest supported version of PowerCLI, which can be downloaded here.

PowerShell is a scripting language Microsoft developed to help administrators manage the Windows environment. Third parties can write their own snap-ins (dynamic linked libraries) to implement new commands, which are called cmdlets. With VDSPowerCli, users can use the cmdlets provided by PowerCLI to manage vSphere Distributed Switch(VDS).

Features

VDSPowerCli gives you the ability to manage:

  • VMware vSphere Distributed Switch
  • Distributed Port Group
  • Distributed Port

Fling Labs: vCenter Cluster Performance Tool

Source: Fling Labs

vCenter Cluster Performance Tool is a Powershell script that uses vSphere PowerCLI to obtain performance data for a cluster by aggregating information from individual hosts.

You have the following options to specify in the script.

  • An “interval” of 20s or 300s. The default is 20s, and corresponds to real time statistics. 300s corresponds to the 5 min interval statistics.
  • A stats query flag to obtain the list of counter IDs available on the vCenter Server. You can then pass the desired counter ID from that list to obtain Performance metrics for the cluster.

Features

  • Gathers all data of the specified interval type that is available on each host in the specified cluster
  • Easy and a quick way of obtaining performance data for a vCenter cluster
  • Data is saved in a CSV file, which can then easily be fed into any charting software
  • A chart, in PNG format, is also generated for visualization