Re: [ltt-dev] hybrid mode questions
Jerry Hom <[email protected]>
| Newsgroups | gmane.linux.kernel.tracing |
|---|---|
| Message-ID | <[email protected]> |
Hi! I'm revisiting the issue of hybrid mode. I've been testing recently with kernel 2.6.18.3, LTTng 0.6.33, LTTV 0.8.72. Since I'm mainly interested in process info (which currently seems to be in the medium rate channel) and don't need the high rate stuff, I tried running in hybrid mode and then stopping without dumping the flight recorder buffers. The advantage with keeping only the medium and low rate channel is the much smaller log size. However, the problem is that a bunch of process names and pids are missing. The processes seem to be those which start after the initial kernel statedump, and they become generically named "swapper". Also, their pids become '0'. Can this be fixed easily? Could you please point me in the direction to help fix this? On Thu, 14 Sep 2006, Mathieu Desnoyers wrote: > * Jerry Hom ([email protected]) wrote: > > > > I'm excited about the new hybrid mode, thanks! It seems to address > > what I've been thinking. Namely, I'm trying to gather a day long > > trace (eg, 8 hours), but the file sizes can reach 10GB+. I have a > > question though about the high rate events in the flight recorder > > buffer. Will that buffer always be dumped when the tracing is > > stopped? > > > > Only is the lttd daemon for reading (only) the flight recorder buffers is > spawned before the trace channel are destroyed. In the lttctl sequence of > operation I explained in the email earlier, yes, the flight recorder channels > are dumped and only then the trace channels are destroyed. > > > Actually, for my purposes, I'm much more interested in the low rate > > events such as processes. Perhaps a nice feature would be a toggle > > switch to turn on/off the high/medium/low rate events individually? > > > > Yes, and eventually, it would be great to multiplex them on the fly per event or > per facility. I guess it will eventually come as an extension to the filter > kernel module for dynamic event filtering (it's not implemented at all yet). > > I'm glad it suits your needs! > > Mathieu > > > > -- > > Jerry Hom > > > > _______________________________________________ > > ltt-dev mailing list > > [email protected] > > http://www.listserv.shafik.org/listserv/listinfo/ltt-dev > > > OpenPGP public key: http://krystal.dyndns.org:8080/key/compudj.gpg > Key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 > -- Jerry Hom