Chapter 8. Compiler and Tools


SystemTap is a tracing and probing tool that allows users to study and monitor the activities of the operating system (particularly, the kernel) in fine detail. It provides information similar to the output of tools like netstat, ps, top, and iostat; however, SystemTap is designed to provide more filtering and analysis options for collected information.

SystemTap in Red Hat Enterprise Linux 5.8 is updated to version 1.6, providing:
  • Kernel modules with a hyphen ("-") in their name, such as i2c-core are now handled properly.
  • process.mark now supports $$parms for reading probe parameters.
  • Improved and simplified operation of the SystemTap compile-server and client:
    • compile-server may cache script build results for improved performance.
    • compile-server and client communicate to exchange version information to adjust the communication protocol accordingly and use the newest version of the server possible.
    • Removal of deprecated tools: stap-client, stap-authorize-server-cert, stap-authorize-signing-cert, stap-find-or-start-server, and stap-find-servers.
  • For remote execution, the --remote USER@HOST functionality can now be specified multiple times and will automatically build the script for distinct kernel and architecture configurations, and run it on all named machines at once.
  • The staprun utility now allows multiple instances of the same script to be run at same time.
  • A new tz_ctime() function prints the local time zone time.
  • New HZ() and jiffies() functions have been added for lightweight approximate time keeping.