The Statistics display (see Figure 2-9) provides data about your application's overall performance and system resource usage (as opposed to the Histogram, Cumulative, and Address Space display options, which show data broken down by program components such as functions and pages). The information provided by the Statistics display is useful when you want to compare actual numerical values against any previous estimates you may have made.
The information needed to produce the Statistics display is always collected by the Sampling Collector during the data collection process, so you do not need to specify any particular data type to view information in this display. The Statistics display shows:
Minor Page Faults | The number of page faults serviced that do not require any physical I/O activity |
Major Page Faults | The number of page faults serviced that require physical I/O activity (if non-zero, the Overview display shows text page or data page fault wait time) |
Process swaps | The number of times a process is swapped out of main memory |
Input blocks | The number of times a read() system call is performed on a non-character or special file |
Output blocks | The number of times a write() system call is performed on a non-character or special file |
Messages sent | The number of messages sent over sockets |
Messages received | The number of messages received from sockets |
Signals handled | The number of signals delivered or received |
Voluntary context switches | The number of times a context switch occurred because a process voluntarily gave up the processor before its allotted time was completed, to wait for availability of a resource |
Involuntary context switches | The number of times a context switch occurred because a higher-priority process became runnable, or because the current process exceeded its allotted time |
System calls | The total number of system calls |
Characters of I/O | The number of characters transferred in or out to a character device or file by read and write calls |
Total address space size | Total size of the address space (in pages) |
Maximum address space size | Maximum size of the address space (pages per sample) |
Minimum address space size | Minimum size of the address space (pages per sample) |
Average address space size | Average size of the address space (pages per sample) |
Total text address space size | Total size of the text address space (pages) |
Maximum text address space size | Maximum size of the text address space (pages per sample) |
Minimum text address space size | Minimum size of the text address space (pages per sample) |
Average text address space size | Average size of the text address space (pages per sample) |
Total non-text address space size | Total size of the non-text address space (pages) |
Maximum non-text address space size | Maximum size of the non-text address space (pages per sample) |
Minimum non--text address space size | Minimum size of the non-text address space (pages per sample) |
Average non-text address space size | Average size of the non-text address space (pages per sample) |
Workset sizes will be non-zero only if address-space data was collected.
You can select which samples to include in the Statistics display in three ways:
Type sample numbers directly into the Includes Samples text field: separate numbers with commas (1,3,6), and define ranges using a hyphen (1-6).
Select the columns containing those samples while still in the Overview display.
Choose either View Select or View Select None while still in the Overview display to include or exclude all samples in the experiment.