Re: Xen, oprofile, perf, PEBS, event counters, PVHVM, PV

[Boris Ostrovsky <boris.ostrovsky@amd.com>]

On 01/15/2013 11:47 PM, Konrad Rzeszutek Wilk wrote:
> On Tue, Jan 15, 2013 at 05:11:01PM +0000, Marcus Granado wrote:
>> On 14/01/13 20:45, Konrad Rzeszutek Wilk wrote:

>>> And it occurs to me it could be possible be to make some inroads on making
>>> performance monitoring easier:
>>>
>>>    1). fix the glaring omissions in oprofile for the new CPUs
>>>    2). Add a register keyhandle to get some debug info.
>>>    3). piggyback on oprofile hypercalls and insert some bridge in perf (lots
>>>        of handwaving here). Or perhaps emulate in the Linux kernel the
>>>        wmsrs (so xen_safe_wrmsrs) and have the pvops kernel based on the MSRs
>>>        make the hypercalls to setup the buffers, etc.
>>>
>>>       3a). new hypercalls? intercept rdmsr/wrmsrs and stuff the right data
>>>        in the initial domain? Other thoughts?
>>>
>>>    4). Extend perf to have '--xen' so it can also look at the xen-hypervisor
>>>        ELF file.
>>
>> 5) live event reports from xenoprof/opreport, ala perf top.
>> 6) ports of oprofile kernel modules for other oses (bsd, windows,
>> mirage), so that these oses can be used as active participants.

(+ Suravee)

What is the status of oprofile development in general (on Linux)? I 
don't see a whole lot of activity there, it appears to be more in 
maintenance mode.

I realize that doing (4) may end up being a lot of work but given much 
more active perf development it seems to me that this should be the 
preferred route.

-boris