Performance tools for the AIX environment fall into two general categories: those that tell you what is going on and those that let you do something about it. A few do both. This appendix lists these performance-related commands. Many of them are discussed in the chapters on tuning specific aspects of the system. The details of the syntax and functions of most of these commands are documented in the AIX Version 4.3 Commands Reference. The schedtune, pdt_config, pdt_report, and vmtune commands are documented later in this appendix.
Some of the performance-related commands are packaged as part of the Performance Toolbox for AIX (PTX), rather than the AIX Base Operating System. Those commands are identified with (PTX). You can determine whether the PTX tools have been installed with:
$ lslpp -lI perfagent.tools
If this package is listed as AVAILABLE, the PTX tools can be used.
The following lists summarize the performance-related commands:
These tools give you information on the performance of one or more aspects of the system or on one or more of the parameters that affect performance.
| Command | Function |
|---|---|
| bf, bfrpt | Provides detailed reports of the memory-access patterns of applications. |
| emstat | Reports emulation instruction counts. |
| filemon | Uses the trace facility to report on the I/O activity of physical volumes, logical volumes, individual files, and the Virtual Memory Manager. |
| fileplace | Displays the physical or logical placement of the blocks that constitute a file within the physical or logical volume on which they reside. |
| gprof | Reports the flow of control among the subroutines of a program and the amount of CPU time consumed by each subroutine. |
| iostat | Displays utilization data for:
|
| lockstat | Displays information about kernel lock contention. |
| lsattr | Displays attributes of the system that affect performance, such as:
|
| lslv | Displays information about a logical volume. |
| netpmon | Uses the trace facility to report on network activity, including:
|
| netstat | Displays a wide variety of configuration information and statistics on communications activity, such as:
|
| nfso | Displays (or changes) the values of NFS options |
| nfsstat | Displays statistics on Network File System (NFS) and Remote Procedure Call (RPC) server and client activity |
| no | Displays (or changes) the values of network options, such as:
|
| pdt_config | Starts, stops, or changes the parameters of the Performance Diagnostic Tool. |
| pdt_report | Generates a PDT report based on the current historical data. |
| ps | Displays statistics and status information about the processes in the system, such as:
|
| sar | Displays statistics on operating-system activity such as:
|
| schedtune | Displays (or changes) the values of VMM memory-load-control parameters, the CPU-time-slice duration, and the paging-space-low retry interval. |
| smit | Displays (or changes) system-management parameters. |
| stem | Supports the entry and exit instrumentation of executable programs without requiring access to the source code of the executable. |
| svmon | Reports on the status of memory at system, process, and segment levels |
| syscalls | Records and counts system calls |
| time | Prints the elapsed and CPU time used by the execution of a command |
| tprof | Uses the trace facility to report the CPU consumption of kernel services, library subroutines, application-program modules, and individual lines of source code in the application program |
| trace | Writes a file that records the exact sequence of activities within the system |
| vmstat | Displays VMM data, such as:
|
| vmtune | Displays (or changes) the Virtual Memory Manager page-replacement algorithm parameters. |
The following tools allow you to change one or more performance-related aspects of the system.
| Command | Function |
|---|---|
| fdpr | Optimizes executable files for a specific workload. |
| nfso | Changes (or displays) the values of NFS options |
| nice | Executes a command at a specified priority |
| no | Changes (or displays) the values of network options |
| renice | Changes the priority of running processes |
| reorgvg | Reorganizes elements of a volume group. |
| rmss | Temporarily reduces the effective RAM size of a system to assess the probable performance of a workload on a smaller machine or to ascertain the memory requirement of one element of a workload. |
| schedtune | Changes (or displays) the values of VMM memory load control parameters, the CPU-time-slice duration, and the paging-space-low retry interval. |
| smit | Changes (or displays) system-management parameters. |
| vmtune | Changes (or displays) the Virtual Memory Manager page-replacement algorithm parameters. |
Commands Overview in AIX Version 4.3 System User's Guide: Operating System and Devices describes how to read syntax diagrams.