* Amit Margalit ([email protected]) wrote: > Hello, > > I'm trying to understand the trade-offs involved in choosing sub-buffer > number and size. > > So the question is what are the benefits and the disadvantages of > choosing, say, 32 subbuffers of 1MB versus 8 subbuffers of 4MB, or maybe 4 > subbuffers of 8MB?
Boundaries of subbuffers are synchronization points, so you add slightly more overhead with smaller sub-buffers. This is an argument for having few large sub-buffers. Also, with periodical timer flush (useful for upcoming streaming feature), you might want more than two sub-buffers per buffer, because otherwise, you might run into situations where the buffer appears to be full (and therefore events are discarded) just because the timer flush flushes a sub-buffer before it is filled. This is an argument for not making the number of sub-buffers _too_ small if you use switch timer. Hoping this helps, Mathieu > > Thanks, > > Amit Margalit > IBM XIV - Storage Reinvented > XIV-NAS Development Team > Tel. 03-689-7774 > Fax. 03-689-7230 > _______________________________________________ > lttng-dev mailing list > [email protected] > http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
