[ltt-dev] Crash recovery of traces and final TSC

Pierre-Marc Fournier pierre-marc.fournier at polymtl.ca
Wed Jul 22 12:12:32 EDT 2009

Mathieu Desnoyers wrote:
> * Michel Dagenais (michel.dagenais at polymtl.ca) wrote:
>>>> When the system crashes, the end timestamp is not written in the
>>>> subbuffer header. Instead, the value 0 is written. This tends to make
>>>> LTTV crash.
>> Obviously LTTV should not "crash", whatever the input :-).
>>>> - "repair" the trace a posteriori, writing in the header the timestamp
>>>> of the last event found in the subbuffer?
>>> Yep, seems like an appropriate solution.
>>>> - change lttv not to not need the "end timestamp" header field?
>>> Hrm, it needs it for quickly seeking to specific sub-buffers.
>> People may expect the trace to be readonly, so relying on a posteriori
>> fixing is kind of unexpected. You could have a special case for the last
>> subbuffer, then not looking at the end time.
> When we will create an index for variable-length sub-buffers, the fixup
> could be computed and added to this index, if needed.

Do we know when this is expected to be done?

> I agree that the trace should stay read-only.


> Mathieu

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