On Thu, 11 Mar 2021 09:44:01 -0500 Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > Dario, feel free to comment on this as well. The host-guest is the > information stored in each guest file that tells it how its TSC matches the > host (if -C is not used in the record). The ts2nsecs is done on the host > where it reads the perf data to find out how the kernels converts the TSC > to nanoseconds, and this information is stored in each trace.dat file (host > and guest). This email is about how those will affect the current options > listed above. Correction, it's the ts2nsecs that is not done if -C is specified on the record command line. The host / guest is done if the two can agree on a protocol. If -C is not specified, and the host knows exactly how the guest TSC is set, and it has information (from perf) on how to convert TSC to nanoseconds, then it will use the TSC clock by default and place the information needed to convert TSC to nanoseconds in each trace.dat file. -- Steve
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