Hi all, I have a customer who has a strange problem with building DTrace probes into their own code. They describe it as:
> We are seeing issues with custom dtrace probes we have added to our > application code, where some of the probe points we have defined are > not present; see below for details. Can you please look into this > problem and suggest a next step (or let us know if there are any > limitations in this area that we should be aware of). > > Background > > Our application code includes many (around 90 or so) libraries which > are dynamically loaded from the main executable with a dlopen() call > at start of day. > > We have defined a dtrace provider which defines several custom dtrace > probes we use in our application code. The .d file for this provider > and its probes is included in the makefiles for each of our > application's libraries. Each library typically includes multiple > instances of the dtrace probe (using the DTRACE_PROBE<n> macros). > > Issue > > We are seeing that only some of the probe points for these custom > probes are accessible to dtrace scripts. Listing the probes using > "dtrace -l -P <provider name> <pid>" only shows all the probe types, > but only a subset of the probe points that we'd expect to see. > > * There is no clear pattern as to which libraries do have the > probe points which we'd expect and which do not. > * We build different configurations of our application code in > which a different subset of our libraries are loaded. > Comparing the probe points from different configurations shows > that we're not always missing the same probe points - i.e. > configurations A and B both include library x, but x has the > correct probe points in configuration A but not in > configuration B. As both configurations use the same library, > this suggests there isn't anything wrong with particular > libraries, but rather that we are hitting some sort of limit > at runtime. I asked them for a small test case, and they can't rip something out, only provide a section of their code, which they'd prefer to keep that under NDA, so I can't post it to this alias. Can someone help us figure this out? Ta, Mark _______________________________________________ dtrace-discuss mailing list dtrace-discuss@opensolaris.org
