Re: [lttng-dev] Tracepoints overhead in x86_64

2013-08-31 Thread Mathieu Desnoyers
* Gianluca Borello (g.bore...@gmail.com) wrote: Hello, This question is more focused on tracepoints rather than LTTng, so feel free to point me at LKML if I'm too off topic. I am looking for a way to trace all the system call activity 24/7 (and do some very customized processing, so LTTng

Re: [lttng-dev] [RFC] adding into middle of RCU list

2013-08-31 Thread Paul E. McKenney
On Thu, Aug 29, 2013 at 07:16:37PM -0700, Josh Triplett wrote: On Thu, Aug 29, 2013 at 05:57:33PM -0700, Paul E. McKenney wrote: On Fri, Aug 23, 2013 at 02:08:22PM -0700, Paul E. McKenney wrote: On Fri, Aug 23, 2013 at 01:16:53PM -0400, Mathieu Desnoyers wrote: #define

Re: [lttng-dev] Tracepoints overhead in x86_64

2013-08-31 Thread Gianluca Borello
On Aug 31, 2013 1:21 PM, Mathieu Desnoyers mathieu.desnoy...@efficios.com wrote: My recommendation would be to implement a dummy trace_sys_enter and trace_sys_exit, and then benchmark the overhead of enabling system call tracing (this will set TIF_SYSCALL_TRACEPOINT in every thread). So at