[dtrace-discuss] libdtrace and xcalls
Hi all I've got an app that periodically runs dtrace scripts through libdtrace and am seeing a good amount of xcalls from that. I understand why dtrace uses xcalls, so this is an expected behavior to a certain extent. But because my app repeats the scripts on an interval basis, the amount of xcalls is higher than I'd like it to be. Is there anything I can do to reduce that ? thanks Rafael ___ dtrace-discuss mailing list dtrace-discuss@opensolaris.org
Re: [dtrace-discuss] libdtrace and xcalls
I've got an app that periodically runs dtrace scripts through libdtrace and am seeing a good amount of xcalls from that. I understand why dtrace uses xcalls, so this is an expected behavior to a certain extent. But because my app repeats the scripts on an interval basis, the amount of xcalls is higher than I'd like it to be. Is there anything I can do to reduce that ? Yes: you can slow down your various rates (switchrate, aggrate, etc.) But the xcalls are probably more cosmetic than an actual problem: DTrace's xcalls execute very quickly, and are unlikely to be causing system-wide degradation. (This is true of essentially all xcalls -- xcalls are more likely to be a symptom of a larger problem than a problem in and of themselves.) Which raises a question: how many xcalls are you seeing, and have you used DTrace to make sure that they're all coming from DTrace? - Bryan -- Bryan Cantrill, Sun Microsystems Fishworks. http://blogs.sun.com/bmc ___ dtrace-discuss mailing list dtrace-discuss@opensolaris.org
Re: [dtrace-discuss] libdtrace and xcalls
On Tue, May 20, 2008 at 12:26 AM, Bryan Cantrill [EMAIL PROTECTED] wrote: I've got an app that periodically runs dtrace scripts through libdtrace and am seeing a good amount of xcalls from that. I understand why dtrace uses xcalls, so this is an expected behavior to a certain extent. But because my app repeats the scripts on an interval basis, the amount of xcalls is higher than I'd like it to be. Is there anything I can do to reduce that ? Yes: you can slow down your various rates (switchrate, aggrate, etc.) But the xcalls are probably more cosmetic than an actual problem: DTrace's xcalls execute very quickly, and are unlikely to be causing system-wide degradation. (This is true of essentially all xcalls -- xcalls are more likely to be a symptom of a larger problem than a problem in and of themselves.) Which raises a question: how many xcalls are you seeing, and have you used DTrace to make sure that they're all coming from DTrace? I'm not sure how many amount of xcalls is higher than you expect. You could find the root cause by: # dtrace -n 'xcalls [EMAIL PROTECTED]()]=count()]}' Thanks, -Aubrey ___ dtrace-discuss mailing list dtrace-discuss@opensolaris.org
