[ltt-dev] Is Lttng able to work as a printk-like function？

[jerome zh]

2010/6/2 Mathieu Desnoyers <compudj at krystal.dyndns.org>
>
> * jerome zh (jeromezhr at gmail.com) wrote:
> > Hi all,
> >
> > In our projects, we used to call printk() in the ip stack to show some ip
> > header information each time a packet comes in.
> > But when the packet comes too frequently, the system becomes overload
> > because of  too many printk().
> > So we are wondering if we can do this by lttng, since its performance is
> > quite high?
>
> LTTng achieve high throughput by _not_ pretty-printing all the
> information to the console like printk() does. So you can output the
> information at high volume using LTTng, but expect to use an output
> different from the console.

I'm sorry but what do you mean by "_not_ pretty-printing" and "output
the information at high volume using LTTng, but expect to use an
output different from the console."
Is lttng able to output the information immediately instead of saving
to files and check it in lttv later?

> If you want to save printk-like information to the trace (e.g.
> format-string based calls), you should use the "trace_mark()" statements
> (Markers).
>

I have finished this feature. Will the buffer overflow if there are
too many information to save?

--
Regards,

Jerome