Overhead of ring buffer in Ftrace

2019-08-01 Thread Fang Zhou
Hi all, I’m currently using Ftrace with tracepoints to trace several events in kernel. But I found the tracing overhead is a little high. I found the major overhead comes from “local_dec(_buffer->committing);” in rb_end_commit() function. local_dec() will invoke atomic_long_dec(), which finally

Re: Overhead of ring buffer in Ftrace

2019-08-06 Thread Fang Zhou
Any ideas or suggestions? Best, Tim On Fri, Aug 2, 2019 at 1:41 AM Fang Zhou wrote: > > Hi all, > > I’m currently using Ftrace with tracepoints to trace several events in > kernel. But I found the tracing overhead is a little high. > > I found the major overhead comes from