System Object

The System performance object consists of those counters that apply to more than one component on the computer

File Read Operations/sec

File Read Operations/sec is the combined rate of file system read requests to all devices on the computer, including requests to read from the file system cache. It is measured in numbers of reads.

Detail Level: Novice
Counter Type: PERF_COUNTER_COUNTER

File Write Operations/sec

File Write Operations/sec is the combined rate of the file system write requests to all devices on the computer, including requests to write to data in the file system cache. It is measured in numbers of writes.

Detail Level: Novice
Counter Type: PERF_COUNTER_COUNTER

File Control Operations/sec

File Control Operations/sec is the combined rate of file system operations that are neither reads nor writes, such as file system control requests and requests for information about device characteristics or status. This is the inverse of System: File Data Operations/sec and is measured in numbers of operations.

Detail Level: Advanced
Counter Type: PERF_COUNTER_COUNTER

File Read Bytes/sec

File Read Bytes/sec is the overall rate at which bytes are read to satisfy file system read requests to all devices on the computer, including reads from the file system cache. It is measured in numbers of bytes.

Detail Level: Expert
Counter Type: PERF_COUNTER_BULK_COUNT

File Write Bytes/sec

File Write Bytes/sec is the overall rate at which bytes are written to satisfy file system write requests to all devices on the computer, including writes to the file system cache. It is measured in numbers of bytes.

Detail Level: Expert
Counter Type: PERF_COUNTER_BULK_COUNT

File Control Bytes/sec

File Control Bytes/sec is the overall rate at which bytes are transferred for all file system operations that are neither reads nor writes, including file system control requests and requests for information about device characteristics or status. It is measured in numbers of bytes.

Detail Level: Wizard
Counter Type: PERF_COUNTER_BULK_COUNT

Context Switches/sec

Context Switches/sec is the combined rate at which all processors on the computer are switched from one thread to another. 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. It is the sum of Thread: Context Switches/sec for all threads running on all processors in the computer and is measured in numbers of switches. There are context switch counters on the System and Thread objects.

Detail Level: Advanced
Counter Type: PERF_COUNTER_COUNTER

System Calls/sec

Systems Calls/sec is the combined rate of calls to Windows NT system service routines by all processes running on the computer. These routines 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.

Detail Level: Advanced
Counter Type: PERF_COUNTER_COUNTER

Total Processor Time

% Total Processor Time is the average percentage of time that all processors on the computer are executing non-idle threads. This counter was designed as the primary indicator of processor activity on multiprocessor computers. It is equal to the sum of Process: % Processor Time for all processors, divided by the number of processors. It is calculated by summing the time that all processors spend executing the thread of the Idle process in each sample interval, subtracting that value from 100%, and dividing the difference by the number of processors on the computer. (Each processor has an Idle thread which consumes cycles when no other threads are ready to run.) For example, on a multiprocessor computer, a value of 50% means that all processors are busy for half of the sample interval, or that half of the processors are busy for all of the sample interval.

Detail Level: Novice
Counter Type: PERF_100NSEC_TIMER_INV

Total User Time

% Total User Time is the average percentage of non-idle time all processors spent in User mode. It is the sum of Processor: % User Time for all processors on the computer, divided by the number of processors. System: % Total User Time and System: % Total Privileged Time sum to % Total Processor Time, but not always to 100%. (User mode is a restricted processing mode designed for applications, environment subsystems, and integral subsystems. The alternative, privileged mode, is designed for operating system components and allows direct access to hardware and all memory. The operating system switches application threads to privileged mode to obtain operating system services.)

Detail Level: Advanced
Counter Type: PERF_100NSEC_TIMER

Total Privileged Time

% Total Privileged Time is the average percentage of non-idle time all processors spent in privileged (kernel) mode. It is the sum of Processor: % Privileged Time for all processors on the computer, divided by the number of processors. System: % Total User Time and System: % Total Privileged Time sum to % Total Processor Time, but not always to 100%. (Privileged mode is an processing mode designed for operating system components which allows direct access to hardware and all memory. The operating system switches application threads to privileged mode to obtain operating system services. The alternative, user mode, is a restricted processing mode designed for applications and environment subsystems.)

Detail Level: Advanced
Counter Type: PERF_100NSEC_TIMER

Total Interrupts/sec

Total Interrupts/sec is the combined rate of hardware interrupts received and serviced by all processors on the computer It is the sum of Processor: Interrupts/sec for all processors, and divided by the number of processors, and is measured in numbers of interrupts. It does not include DPCs, which are counted separately. This value is an indirect indicator of the activity of devices that generate interrupts, such as the system timer, the mouse, disk drivers, data communication lines, network interface cards and other peripheral devices. These devices normally interrupt the processor when they have completed a task or require attention. Normal thread execution is suspended during interrupts. Most system clocks interrupt the processor every 10 milliseconds, creating a background of interrupt activity.

Detail Level: Advanced
Counter Type: PERF_COUNTER_COUNTER

File Data Operations/sec

File Data Operations/sec is the combined rate of read and write operations on all logical disks on the computer. This is the inverse of System: File Control Operations/sec.

Detail Level: Novice
Counter Type: PERF_COUNTER_COUNTER

System Up Time

Total Time (in seconds) that the computer has been operational since it was last started.

Detail Level: Novice
Counter Type: PERF_ELAPSED_TIME

Processor Queue Length

Processor Queue Length is the number of threads in the processor queue. There is a single queue for processor time even on computers with multiple processors. Unlike the disk counters, this counter counts ready threads only, not threads that are running. A sustained processor queue of greater than two threads generally indicates processor congestion.

Detail Level: Wizard
Counter Type: PERF_COUNTER_RAWCOUNT

Alignment Fixups/sec

Alignment Fixups/sec is the rate of alignment faults fixed by the system.

Detail Level: Wizard
Counter Type: PERF_COUNTER_COUNTER

Exception Dispatches/sec

Exception Dispatches/sec is the rate of exceptions dispatched by the system.

Detail Level: Wizard
Counter Type: PERF_COUNTER_COUNTER

Floating Emulations/sec

Floating Emulations/sec is the rate of floating emulations performed by the system.

Detail Level: Wizard
Counter Type: PERF_COUNTER_COUNTER

% Total DPC Time

% Total DPC Time is the average percentage of time that all processors spent receiving and servicing deferred procedure calls (DPC). (DPCs are interrupts that run at a lower priority than the standard interrupts.) it is the sum of Processor: %DPC Time for all processors on the computer, divided by the number of processors. System: %Total DPC Time is a component of System: %Total Privileged Time because DPCs are executed in privileged mode. DPCs are counter separately and are not a component of the interrupt count.

Detail Level: Advanced
Counter Type: PERF_100NSEC_TIMER

% Total Interrupt Time

% Total Interrupt Time is the average percentage of time that all processors spent servicing interrupts. It is the sum of Processor: % Interrupt Time for of all processors on the computer, divided by the number of processors. DPCs are counted separately and are not a component of the interrupt count. This value is an indirect indicator of the activity of devices that generate interrupts, such as the system timer, the mouse, disk drivers, data communication lines, network interface cards and other peripheral devices.

Detail Level: Advanced
Counter Type: PERF_100NSEC_TIMER

Total DPCs Queued/sec

Total DPCs Queued/sec is the combined rate at which deferred procedure calls (DPC) are added to the DPC queue of all processors on the computer. (DPCs are interrupts that run at a lower priority than standard interrupts.) Each processor has its own DPC queue. This counter measures the rates at which DPCs are added to the queue, not the number of DPCs in the queue. It is the sum of Processor: DPCs Queued/sec for all processors on the computer, divided by the number of processors.

Detail Level: Advanced
Counter Type: PERF_COUNTER_COUNTER

Total DPC Rate

Total DPC Rate is the combined rate at which deferred procedure calls (DPCs) are added to the DPC queues of all processors between timer tics of each processor's system clock. (DPCs are interrupts that run at a lower priority than standard interrupts.) Each processor has its own DPC queue. clock on the processor. This counter measures the rate at which DPCs are added to the queue, not the number of DPCs in the queue. It is the sum of Processor: DPC Rate for all processors on the computer, divided by the number of processors.

Detail Level: Advanced
Counter Type: PERF_COUNTER_RAWCOUNT

Total DPC Bypasses/sec

Total DPC Bypasses/sec is the combined rate at which deferred procedure calls (DPCs) on all processors were avoided. (DPCs are interrupts that run at a lower priority than standard interrupts.) . This value is the sum of Processor: DPC Bypasses/sec for all processors, divided by the number of processors.

Detail Level: Advanced
Counter Type: PERF_COUNTER_COUNTER

Total APC Bypasses/sec

Total APC Bypasses/sec is the combined rate at which kernel asynchronous procedure call (APC) interrupts on all processors were avoided. This value is the sum of Processor: APC Bypasses/sec for all processors, divided by the number of processors.

Detail Level: Advanced
Counter Type: PERF_COUNTER_COUNTER

%Registry Quota In Use

% Registry Quota In Use is the percentage of the Total Registry Quota Allowed that is currently being used by the system.

Detail Level: Advanced
Counter Type: PERF_RAW_FRACTION

Registry Quota In Use

% Registry Quota In Use indicates the percentage of the Total Registry Quota Allowed currently in use by the system.

Detail Level: Advanced
Counter Type: PERF_RAW_BASE