4 ms·

Can you explain this a bit more? It sounds interesting.

• VMG 14y ago
  This allows developers to see what their programs are doing in more detail. They can then use that information to optimize their code.
  • tocomment 14y ago
    There's nothing similar in older linuxes?
    • deweerdt 14y ago
      There is, strace does just that. perf trace is still evolving though and appears promising. See, for example, scripting support: http://lwn.net/Articles/371448/ http://lwn.net/Articles/371448/
    • jiggy2011 14y ago
      You can already see system calls with strace.
• majke 14y ago
  Linux is suffering from a lack of a good debugging API. There is a decent progress in the kernel debugging and profiling tools, but for userspace no changes were made for a long time. "ptrace" is the main userspace debugging API, used behind tools like "strace" or "gdb", but it's old and clumsy. Quite new "perf" tool, on the other hand, allows user to get various CPU/Kernel stats mostly useful for profiling. Before "perf" you could only try to emulate your program using "valgrind" to get, say cache misses. The command "perf trace", seems to move "perf" more into the "ptrace" domain. This is indeed exciting.