[lttng-dev] Sub-buffer multiplicity on multi-core systems

[Thibault, Daniel]

   I understand that each processor can be understood as generating its own event stream (for a given event).  Assume a quad-core system.  At which point are the four event streams merged into one?  What I mean is: is the ring buffer which represents a kernel channel for a given session (for example) actually four ring buffers (one per CPU), or just one?  I suspect the merge occurs early (at the LTTng kernel module level), but I want to be sure.  (I understand that the four streams remain distinct in the logical CTF sense: what I'm wondering about here is the sub-buffer multiplicity)

Daniel U. Thibault
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