From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel.Thibault@drdc-rddc.gc.ca (Thibault, Daniel) Date: Tue, 4 Feb 2014 15:24:41 +0000 Subject: [lttng-dev] About Lttng trace mode Message-ID: <48CF5AC71E61DB46B70D0F388054EFFD267DE171@VAL-E-02.valcartier.drdc-rddc.gc.ca> Date: Mon, 3 Feb 2014 16:03:14 +0000 (UTC) From: Mathieu Desnoyers >----- Original Message ----- >> From: "Daniel Thibault" >> Sent: Thursday, November 14, 2013 12:01:25 PM >> >> [...] >> or by the consumer. In discard mode, while a sub-buffer is locked for >> consumer access, should the writers go around the set of sub-buffers and >> [...] > >The paragraph above is true, except for the part "while a sub-buffer is locked for consumer access". In discard mode, as soon as the writer is filling up all sub-buffers, and thus the >produced sub-buffers count reaches the consumed sub-buffer count minus the number of sub-buffers in the buffer (this is a buffer full situation), events are discarded. This is done >independently of whether or not the consumer is currently locking a sub-buffer for reading. Good, subtle point. The sub-buffer is marked for consumption ("read-ready"), just not actively locked ("being read"). Daniel U. Thibault Protection des syst?mes et contremesures (PSC) | Systems Protection & Countermeasures (SPC) Cyber s?curit? pour les missions essentielles (CME) | Mission Critical Cyber Security (MCCS) R & D pour la d?fense Canada - Valcartier (RDDC Valcartier) | Defence R&D Canada - Valcartier (DRDC Valcartier) 2459 route de la Bravoure Qu?bec QC G3J 1X5 CANADA Vox : (418) 844-4000 x4245 Fax : (418) 844-4538 NAC : 918V QSDJ Gouvernement du Canada | Government of Canada