| Measurement |
Description |
Measurement
Unit |
Interpretation |
| Processes_count |
The number of processes running on the system |
Number |
|
| Threads_count |
The number of threads in the system
|
Number |
|
| Registry_quota_in_use |
The percentage of registry quota currently in use by the system
|
Percent |
If this measure begins to reach 100%, we need to increase the total registry size set in Control Panel/System's Virtual Memory tab.
|
| Context_switches_rate |
This value is the combined rate at which all
processors on the computer are switched from one thread to another.
|
Switches/Sec |
Context switches occur when a running thread voluntarily relinquishes the
processor, is preempted by a higher priority ready thread, or switches
between user-mode and privileged (kernel) mode to use an Executive or
subsystem service. If the context switch rate is unusually high, it implies
that
there is excessive contention for CPU resources.
|
| System_calls_rate |
This value is the combined rate of calls to operating
system service routines by all processes running on the computer.
|
Calls/Sec |
Operating system calls are used to perform all of the basic scheduling and
synchronization of activities on the computer, and provide access to
non-graphic devices, memory management, and name space management.
Excessively high number of system calls can impact the performance of a
system. Watch for processes that are issuing a large number of system calls.
Applications corresponding to these processes could be candidates for
performance optimizations.
|
| Pin_read_hits |
The percentage of pin read requests that hit the file
system cache, i.e., did not require a disk read in order to provide access
to the page in the file system cache
|
Percent |
While pinned, a page's physical address in the file system cache will not be
altered. The LAN Redirector uses this method for retrieving data from the
cache, as does the LAN Server for small transfers. This is usually the
method used by the disk file systems as well. The pin read hits should be
close to 100% for high performance.
|
| Pin_read_rate |
The frequency of reading data into the file system cache
preparatory to writing the data back to disk
|
Reads/Sec |
Pages read in this fashion
are pinned in memory at the completion of the read. While pinned, a page's
physical address in the file system cache will not be altered.
|
| Interrupt_time |
Indicates the time spent by the processor for receiving and servicing the hardware interrupts during the last polling interval.
|
Percent |
This is an indirect indicator of the activity of devices that generate interrupts such as system Clocks, the mouse device drivers, data communication lines, network interface cards and other peripheral devices. In general, a very high value of this measure might indicate that a disk or network adapter needs upgrading or replacing.
|