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Error: The following events cannot be collected

Zhu__Mark
Beginner
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Hi,

I'm running VTune Amplifier 2019.5.0.601413 with command line and get the error while trying to collect uarch-exploration or memory-access. Here's the full output:

amplxe: Warning: To profile kernel modules during the session, make sure they are available in the /lib/modules/kernel_version/ location.
amplxe: Error: The following events cannot be collected: MEM_LOAD_UOPS_LLC_MISS_RETIRED.LOCAL_DRAM,MEM_LOAD_UOPS_LLC_MISS_RETIRED.REMOTE_DRAM,MEM_LOAD_UOPS_LLC_MISS_RETIRED.REMOTE_FWD,MEM_LOAD_UOPS_LLC_MISS_RETIRED.REMOTE_HITM,MEM_LOAD_UOPS_RETIRED.L1_MISS. Consider removing the events from the collection, loading the VTune Amplifier sampling driver using the root credentials, or updating the OS kernel.
amplxe: Collection failed.

I'm running from native Ubuntu 14.04 on an ivy bridge CPU. The above hardware events, as described in the error, can be collected using PCM library though. I was able to modify those control registers and read out contents of the counters.

Could you please help? Thanks! 

Mark

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Dmitry_R_Intel1
Employee
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Such error may happen when VTune is used in driver-less mode (through Linux perf). For some reasons certain kernel versions don't  allow to collect these events on Ivy Bridge.

To avoid this error you have following variants:

1. Load VTune driver. With the driver properly installed VTune will use it instead of Linux perf and there will be no such problems

2. Update OS to a newer version. E.g. as I know Ubuntu 16.04 and later don't have this limitation

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Dmitry_R_Intel1
Employee
3,331 Views

Such error may happen when VTune is used in driver-less mode (through Linux perf). For some reasons certain kernel versions don't  allow to collect these events on Ivy Bridge.

To avoid this error you have following variants:

1. Load VTune driver. With the driver properly installed VTune will use it instead of Linux perf and there will be no such problems

2. Update OS to a newer version. E.g. as I know Ubuntu 16.04 and later don't have this limitation

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McCalpinJohn
Honored Contributor III
3,330 Views

This is one of a number of events that have been specifically disabled due to known bugs.     In this case, the bug is errata CA93 in the "Intel Xeon Processor E5 v2 Product Family Specification Update" (document 329189, revision 014, September 2015).

This particular error only applies if HyperThreading is enabled, but in that case it can certainly generated completely bogus results.   I don't remember if the kernel checked to see if HT was enabled before disabling this event....

If I recall correctly, there is also no trouble if the user thread is bound to a specific logical processor (thread) and the sibling logical processor is not used (i.e., is completely idle) during the measurements.  

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