Re: Oprofile buffer size

[Philippe E. <ph...@wa...>]

On Wed, 28 Apr 2004 at 11:15 +0000, Yaoping Ruan wrote:

> Hi,
> well, it is hard to believe it is HTML. My email was written in Netscape
> Inbox with plain text only. This message is from "pine". Hope it can get
> through.

right that's why I didn't undertand the rejection, anyway if it occur again I'll look deeper.

> Back to my question, thanks for the answer. Just confirm that the buffer
> is the event buffer explained in the Internal, not the CPU buffer, right?
> I notice "--buffer-size" option for opcontrol. I assume it is for the
> event buffer. Then is it possible that CPU buffer also overflows? And how

I think you use a 2.4 module, the only relevant parameter is --buffer-size and
--note-table-size (note table size can overflow if there is a lot of fork/exec/mmap).

> can I decrease sampling rate? Is it set by increasing the overflow "count"
> value for each event?

yes, to decrease sampling rate you must increase count with
$ opcontrol --event=XXX:counts, the ~root/.oprofile/daemonrc file
contains your setting which are persistent over different profiling
session, perhaps during experimentation you setup count to a very
low value and don't re set it ?

regards,
Phil