Messages in this thread | | | From | KOSAKI Motohiro <> | Subject | Re: [PATCH 05/16] tracing: show that buffer size is not expanded | Date | Fri, 13 Mar 2009 12:05:53 +0900 (JST) |
| |
> From: Steven Rostedt <srostedt@redhat.com> > > Impact: do not confuse user on small trace buffer sizes > > When the system boots up, the trace buffer is small to conserve memory. > It is only two pages per online CPU. When the tracer is used, it expands > to the default value. > > This can confuse the user if they look at the buffer size and see only > 7, but then later they see 1408. > > # cat /debug/tracing/buffer_size_kb > 7 > > # echo sched_switch > /debug/tracing/current_tracer > > # cat /debug/tracing/buffer_size_kb > 1408 > > This patch tries to help remove this confustion by showing that the > buffer has not been expanded. > > # cat /debug/tracing/buffer_size_kb > 7 (expanded: 1408)
Hi,
I have one question. Why souldn't use following output?
sprintf(buf, "%lu\n", trace_buf_size >> 10);
My point is: - pure number output can hadle easily. - nobody need to know internal memory saving logic.
| |