Disk Reads Alarm
The Disk Reads alarm is activated when the level of traffic being transmitted from this disk exceeds a threshold. Sustained high disk activity can cause an overall degradation of system responsiveness.
When this alarm is current you should look at:
- The Page File Transfers chart on the Paging Activity page of the Memory drilldown. High paging in suggests that the high number of disk reads could be due to system paging. Adding more memory may alleviate the problem.
- The NBT page of the Network drilldown and see if any systems are transferring a large amount of data.
- The Disk Queue chart on the Physical Disks Activity page of the Disks drilldown. If the disk queue length is high on a single physical disk you can look at:
- Spreading frequently accessed data over multiple physical disks.
- Spreading page files over multiple physical disks.
- Implementing a faster disk subsystem.
- Implementing RAID striping technology.
If the high number of reads is causing an overall degradation of the system, consider upgrading the disk subsystem (controller and/or disks).
Related Topics
Summary Page
NBT Page
Physical Disk Activity Page
Disk Writes Alarm
The Disk Writes alarm is activated when the level of traffic being transmitted to this disk exceeds a threshold. Sustained high disk activity can cause an overall degradation of system responsiveness.
When this alarm is current you should look at:
- The Page File Transfers chart on the Paging Activity page of the Memory drilldown. High paging out suggests that the high number of disk writes could be due to system paging. Adding more memory may alleviate the problem.
- The NBT page of the Network drilldown and see if any systems are transferring a large amount of data.
- The Disk Queue chart on the Physical Disks Activity tab of the Disks drilldown. If the disk queue length is high on a single physical disk you can look at:
- Spreading frequently accessed data over multiple physical disks.
- Spreading page files over multiple physical disks.
- Implementing a faster disk subsystem.
- Implementing RAID striping technology.
If the high number of writes is causing an overall degradation of the system, consider upgrading the disk subsystem (controller and/or disks).
Related Topics
Summary Page
NBT Page
Physical Disk Activity Page
Event Log Alarm
This alarm becomes active when an Event Log entry is found which matches an active Event Log rule.
You can enable event logs and set event log rules. Windows Event Log Metrics
Related Topics
Event Log Page
Event Log Panel
Windows Event Log Metrics
Logical Disk Statistics Alarm
This alarm is activated when disk-based performance counters are not enabled or not updated.
Windows 2000
Not all disk-based performance counters are enabled by default on Windows 2000 systems. If this is the case, Spotlight on Windows cannot retrieve the data in these counters, and the disk activity flows (to the left of the Disks panel) are disabled for this machine.
To rectify this situation:
-
Go to the machine's command prompt and type:
diskperf -y
- For this change to take effect, you then need to reboot the system under diagnosis.
Dynamic disks and Windows 2000
Windows 2000 systems now have additional support for dynamic disks, but the disk performance counters under Windows 2000 have not been updated to report this information correctly. Because of this, Spotlight on Windows cannot retrieve the data in these counters, and the disk activity flows (to the left of the Disks panel) are disabled for this machine.
To rectify this situation:
- Remove all dynamic disks from the machine, or
- Upgrade the machine to the Windows XP operating system.
Related Topics
Disks Panel
