Re: [perfmon2] TSX event modifiers for libpfm4

[Stephane E. <er...@go...>]

On Tue, Aug 20, 2013 at 9:56 AM, Bhavishya Goel <bha...@gm...>wrote:

> Hi,
>
> I am trying to use the TSX event modifiers for libpfm4 on Intel Haswell
> microarchitecture. But it doesn't seem to be working for me. The counts
> that I see for performance events are the same with or without the
> intx/intxcp attibute. Following is an example of command that I run:
>
> task -i -e UNHALTED_CORE_CYCLES:intx ./tsx_example
>
> The count for UNHALTED_CORE_CYCLES remains the same with and without intx
> attribute. The intxcp attribute also doesn't make a difference. Intel's
> PCM-TSX tool for the same code shows that cycles spent within transaction
> are only 56% of the total cycles.
>
> And what kernel version are you using?
You need kernel support to get Haswell support. In fact, you need
3.11.0-rc5 or so.
With any older kernels, the tsx modifiers will be ignored.