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Re: Meeting minutes 20060727
Frank Ch. Eigler wrote:
Hi -Actually, in the email that was directed at Masami-san I stated two
scenarios that prevent us just using get_cycles(). One is processors
that support frequency scaling and the second one is virtulized
environments like Xen or Power5 micro partitions. This was something
that Masami-san and myself were discussing at OLS, as one of his main
concerns with LKET the performance impact of do_gettimeofday() as a
timestamp mechanism. The things that I wrote on my email to Masami-san
were a continuation of those discussion we had at OLS in an effort to
standardize the tracing mechanism.
On Thu, Aug 03, 2006 at 03:49:42PM -0500, Jose R. Santos wrote:
> [...] My point is that printing raw cycles will have less of an
> impact than the calculations needed for gettimeofday. [...]
Nothing is keeping you from tracing the value of get_cycles() instead
of a higher level figure.