SolarWinds' Free Storage Response Time Monitor
Utility
SolarWinds supply at least 5 monitors which focus on different
aspects of disk
performance. This is a review of their free tool called Storage
Response Time Monitor, which will help you spot disk performance
problems with Virtual Machines (VMs).
Storage Response Time Monitor Review
The mission is to provides end-to-end storage information.
Having downloaded the free tool to your desktop, the installation
routine asks for the name and logon credentials of the server that hosts
your VMs. See screenshot to the right.
Because it's difficult to give hard-and-fast numbers with computer performance data,
I prefer to concentrate on the relative performance
of the VMs. This is why I like the way this utility shows us
the 10 data-stores with the worst response times.
If you see that the response of one VM is clearly much slower than the
rest, then the next question is, 'Could this bottleneck be at the virtual disk
storage, or is it insufficient memory or CPU power?' Providing you are using Fibre channel or iSCSI, your Storage Response
Time Monitor will differentiate between 'Kernel latency' and 'Device
latency'. You have a virtual disk problem if the IO per second
(IOPS), as displayed by 'Device latency', drops below about 25.
Math Recap With response times, the lower the figure in milli-seconds (ms)
the better.
With eye-ops (IOPS) the larger the number of disk reads and writes
per second, the better. Anyway, no worries because the Storage
Response Time Monitor displays 'Worst 10' and 'Busiest 10' VMs.
Another approach to identifying disk latency would be to count the number of
drives in your physical array, then multiply by the number of IOPS
available for each disk. Now divide by the total number of VMs,
for example:
6 disks x 250 IOPS = 1,500 IOPS Shared amongst 30 VM = 50 IOPS
each.
Let us say that the Storage Response Time Monitor reports that one VM
is down to 12 IOPS (12 input / outputs per second), then the tool has
done its job in highlighting the problem, now it's up to you to delve
deeper. In which case you may need SolarWinds' Storage Manager.
If it's capacity planning that concerns you then Storage Manager is
the tool of choice, because it can show trends, and project when each VM
will run out of disk space. In a nutshell, Storage Response Time
Monitor gives you a quick review of VM disk performance; wheras the
Storage Manager will give you detailed breakdown of the past, present
and future disk space.
SolarWinds Storage Manager Video
Here is a neat way to review SolarWinds Storage Response Time Monitor
How to Install the SolarWinds Storage Response Time Monitor
I found the hardest part of reviewing this gadget was remembering where I
downloaded the zip file! From there it was all downhill. I extracted the .msi file,
double-clicked, acknowledged the
licence agreement, and let the install wizard perform the setup.
After the install completes the utility launches and you are ready to
begin. Should you need 'find' the application later look on the
start menu, or if all else fails navigate to:
Should you need to uninstall, then go to the Control Panel, Programs,
scroll down to 'S' for SolarWinds Storage Response Time Monitor. It's a sign of a good
freeware program that it uninstalls easily and completely. See
more on a live
demo.
Recommendation: Click on the 'Get Geeky' tab and
visit the
Thwack forum.
Summary: Storage Response Time Monitor Review
Here is an interesting free tool from SolarWinds to display response
times for your virtual machines. As the point of creating VM is to
maximise physical resources, Storage Response Time Monitor tool will
identify poor performers, from there you can investigate the root cause,
whether it's disk latency, or a stressed host server.
Free and 30-day Trial Virtual Machine Software
My recommendations for additional handy
utilities. Many of these downloads are free, while others
are fully-functional, but time limited.
SolarWinds are happy to provide you with a free specialist tool, which is ideal for testing, and then
supply a more comprehensive suite for larger organizations. To let you
into a secret, for small networks, the free tool is all you'll ever need.
Guy Recommends:
SolarWinds' NPM - Network Performance Monitor
SolarWinds' performance monitor is designed for detecting network outages,
making it easy to see what's working, and what needs your attention.
This utility guides you through creating network maps; it also helps
identifying whether the
root cause is faulty equipment, or resource overload. Give NPM a try.
