[lttng-dev] [RFC babeltrace 1/2] fs-src: add argument for metadata src dir

[Alexander Aring]

On Tue, May 01, 2018 at 11:43:32AM -0400, Alexander Aring wrote:
...
> > 
> > Normally, a trace has a unique UUID. If you cannot ensure this, I
> > suggest that you remove the UUID field from the packet header.
> > 
> 
> I see, according [0]:
> 
> Trace UUID, used to ensure the event packet match the metadata used.
> Note: we cannot use a metadata checksum in every cases instead of a UUID
> because metadata can be appended to while tracing is active. This field
> is optional.
> 

I removed some other fields which I don't need. Thanks for reminding me!
I removed:


 - Stream-ID: I have only one stream
 - events_discarded: I don't handle this in fs platform right now, could
   be maybe as "filesystem is full?"

May I drop uuid when I have only one metadata file, but validation if
metadata fits or not could be useful for handling the case if somebody
use a different one.

I see that barectf will still generate some uuid and place it in:

trace {
	uuid = ....
};

but I guess it will not be used anymore in the stream. So far I don't
see it anymore with a simple hexdump (Looks for me as the best way to
check what barectf is doing).

Thanks.

- Alex