SUMMARY

This article provides detailed information on how to capture and monitor Disk I/O using the built-in Windows Performance Monitor to help detect potential disk bottlenecks that can affect MailEnable performance.

DETAIL

When managing a mail server, disk I/O is one of the most important factors on how a mail server performs efficiently. If there are bottlenecks or latencies due to disk activity, then it can have a large impact on the MailEnable core services. 

To keep a close eye on disk activity and determine if the server's disks are maxing out Windows Performance Monitor can be used. Perfmon is an easy to use mmc snap in tool that analyses system performance.  

CONFIGURATION

How to configure Perfmon to monitor Disk I/O activity in Real-Time

The steps below provide details on how to configure Perfmon counters to monitor Disk /I/O in Real-time.

Adding the Physical Counters:

1. On the Windows server where MailEnable is installed, open a Windows 'Run' command and enter "perfmon.exe" and clicking OK.
2. In the folder tree node expand: Performance > Monitoring Tools. Click on 'Performance Monitor'. In the righthand pane windows within the toolbar of icons, click the green plus sign (+) icon. The 'Add Counters' window will load in a popup window.
3. In the 'Add Counters' window within the 'Available Counters' list select "PhysicalDisk' and expand. Next within the 'Instances of selected object' section, select the physical disk(s) you want to monitor by selecting the volume letter. To select all physical disks click on '<All Instances>'.
4. Go back to the 'Available Counters' list and expand the 'PhysicalDisk' node. Highlight the following counters by holding the CTRL key on the keyboard and selecting each counter:

• % Disk Read Time
• % Disk Time
• % Disk Write Time
• % Idle Time
• Current Disk Queue Length
• Disk Reads/sec
• Disk Writes/sec
• Split IO/sec

Click 'Add >>' to add the counters within the "Added counters' list. Then click 'OK' to close the 'Add Counters' Window.

There are various ways to monitor perfmon. You can select from 2 types of graphs (Line or Histogram Bar) or a Real-time report. In the perfmon icon toolbar click on 'Change Graph Type' to change to the desired view for monitoring.

How to configure Perfmon to monitor Disk I/O activity over a period of time

Adding a Perfmon Data Collector Set:

1. On the Windows server where MailEnable is installed, open a Windows 'Run' command and enter "perfmon.exe" and clicking OK.
2. Expand Performance > Data Collector Sets. Right Click on 'User Defined' and select: New > Data Collector Set.
3. Specify a name in the 'Name:' field for the Data Collector. I.e.: Disk activity
4. Select the option for 'Create manually (Advanced)' and then click Next.
5. For the type of data to include select the option for 'Create data logs' and tick the box for 'Performance Counter' and then click Next.
6. In the next window click on 'Add..'

7. In the 'Add Counters' window within the 'Available Counters' list select "PhysicalDisk' and expand. Next within the 'Instances of selected object' section, select the physical disk(s) you want to monitor by selecting the volume letter. To select all physical disks, click on '<All Instances>'.

8. Go back to the 'Available Counters' list and expand the 'PhysicalDisk' node. Highlight the following counters by holding the CTRL key on the keyboard and selecting each counter:

• % Disk Read Time
• % Disk Time
• % Disk Write Time
• % Idle Time
• Current Disk Queue Length
• Disk Reads/sec
• Disk Writes/sec
• Split IO/sec

Click 'Add >>' to add the counters within the "Added counters' list. Then click 'OK' to close the 'Add Counters' Window.

1. Back in the 'Performance Counters' window set the 'Sample interval' to 30 seconds and click Next.
2. The next step is to set a path for where the perfmon log file will be saved. Perfmon log file can become quite large in size and therefore a storage drive with adequate storage space is recommended.
3. Finally leave the 'run as:' as 'Default' and select the option for "save and close' and then click 'Finish'.

How to start capturing using the new Data Collector Set:

1. Expand Performance > Data Collector Sets > User Defined > {report name}
2. Right click on the report name and select 'Start'.
3. Once the data has been captured right click the report and select 'Stop'.
4. To access the report, navigate in perfmon to: Performance > Reports > User Defined > {report name}
5. You can also retrieve a copy of the perfmon log file by navigating the path specified in the step 10 above and copying the .blg file. This can then be opened on other machines running Perfmon. This is ideal when logging a support incidence with MailEnable and providing a copy of the report.

REFERENCES

https://technet.microsoft.com/en-us/library/cc771692.aspx#BKMK_Scen6