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From: david.goulet@polymtl.ca (David Goulet)
Subject: [ltt-dev] Kernel and User Space tracers have	different	timestamp reference
Date: Fri, 26 Nov 2010 08:47:38 -0500	[thread overview]
Message-ID: <4CEFBA7A.8060807@polymtl.ca> (raw)
In-Reply-To: <20101126133256.GA22133@Krystal>

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Yes,

And also, the UST patch is done and ready for merge :)

Very soon guys!

David

On 10-11-26 08:32 AM, Mathieu Desnoyers wrote:
> Hi!
> 
> Yesterday evening, Julien and I were actively finishing the vDSO work
> that is needed to have synchronized timestamps between the kernel LTTng
> and UST on x86. It should be ready very soon. Keep posted for a new
> release. :)
> 
> By the way, in the initial implementation, only 64-bit processes on
> 64-bit x86 systems with synchronized TSCs will benefit from the vDSO
> speed. All other x86 setups will fallback on a system call, which will
> still work, albeit being a bit slower.
> 
> Thanks,
> 
> Mathieu
> 
> * Alexandre Montplaisir (alexandre.montplaisir at polymtl.ca) wrote:
>> Hi folks,
>>
>> I've received this bug report about kernel/UST trace synchronization.  
>> Anyone knows what's the status on this?
>>
>> Thanks,
>> Alexandre
>>
>>
>> On 10-11-26 03:24 AM, Florent Boudet wrote:
>>> Hello,
>>>
>>> I am sorry to contact you directly instead of filling a bug, but it
>>> seems the option is disabled on the launchpad project...
>>>
>>> I have recorded userspace traces at the same time as kernel traces, and
>>> opened both with LTTv.
>>> Timestamp for userspace traces and timestamp for kernel traces have
>>> different origins, which make it difficult to analyze.
>>> I am not sure about the cause, this might be related to a GMT/localtime
>>> issue...
>>>
>>> Regards,
>>> Florent Boudet
>>
>>
>> _______________________________________________
>> ltt-dev mailing list
>> ltt-dev at lists.casi.polymtl.ca
>> http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
>>
> 

- -- 
David Goulet
LTTng project, DORSAL Lab.

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  reply	other threads:[~2010-11-26 13:47 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20101126082453.4252.72312.launchpad@wampee.canonical.com>
2010-11-26 13:08 ` Alexandre Montplaisir
2010-11-26 13:32   ` Mathieu Desnoyers
2010-11-26 13:47     ` David Goulet [this message]
2010-11-29 22:43       ` florent boudet

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