On 20.05.10 01:25, Kevin Colwell wrote:
In reviewing some dtrace output I'm confused because something I expect to see is missing. I see a process' thread enter a function but I never see it return. About a minute later I see the same tid active, but in other functions. I'm guessing that perhaps the trace entries were dropped due to buffer overflow, but I don't have the stderr from when it ran so I don't know for sure. Are "drops on cpu" deterministic? Chronologically, would the buffer fill with the first traces and then drop subsequent events, or would it keep on tracing in a circular buffer, overwriting old events and reporting only the latest events that remain in the buffer? If the former, I would expect to see the function return because it should have been the first event of a high activity period.
Dtrace cannot instrument all return functions - I think it's got to do with the way the stack is set up (I think "leaf functions" is the operative word here, I may be wrong though).
I'd suggest you peruse the archives, Adam Leventhal among others has answered this question several times ;-)
HTH Michael -- michael.schus...@oracle.com http://blogs.sun.com/recursion Recursion, n.: see 'Recursion' _______________________________________________ dtrace-discuss mailing list dtrace-discuss@opensolaris.org
