---------------------------------------------------------------------- >> Date: Wed, 16 Apr 2014 18:22:42 +0200 >> From: S?bastien Barth?l?my <[email protected]> >> >> LTTng uses more memory than I expected. On the simple experiment below one >> can see that the "cached" memory increases by >> >> subbuf_size*num_cpu*(num_subbuf+1) >> >> That's not a big deal, but I did not expect the "+1". >> >> Does somebody know where it comes from?
> Date: Wed, 16 Apr 2014 17:32:39 +0000 (UTC) > From: Mathieu Desnoyers <[email protected]> > It is the extra sub-buffer needed for reading a sub-buffer while the > other sub-buffers are written into. It's needed for snapshotting > data while tracing is active. > > Mathieu If I'm not mistaken, the "passing sub-buffer" is used in overwrite mode (as opposed to discard mode), not especially for snapshot mode. It is in fact possible to run in snapshot+discard mode, although that may not be very useful in most use cases. Can you confirm, Mathieu? Daniel U. Thibault Protection des systèmes et contremesures (PSC) | Systems Protection & Countermeasures (SPC) Cyber sécurité pour les missions essentielles (CME) | Mission Critical Cyber Security (MCCS) R & D pour la défense Canada - Valcartier (RDDC Valcartier) | Defence R&D Canada - Valcartier (DRDC Valcartier) 2459 route de la Bravoure Québec QC G3J 1X5 CANADA Vox : (418) 844-4000 x4245 Fax : (418) 844-4538 NAC : 918V QSDJ <http://www.travelgis.com/map.asp?addr=918V%20QSDJ> Gouvernement du Canada | Government of Canada <http://www.valcartier.drdc-rddc.gc.ca/> _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
