<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Arial; font-size: 10pt; color: #000000'>Hi, Scott...<br><br><div style="color: rgb(0, 0, 0); font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;"><div style="margin-left: 40px;">I've been working with Dustin Sallings and Michal Ptaszek to expand the<br>work that they've done on adding DTrace probes to the Erlang virtual<br>machine. We have started preliminary, *informal*, **no-promises-yet**<br>talks with Ericsson's OTP team. Our goal (and not yet the OTP team's, I<br>*cannot* speak for them) is to get these probes & NIF code into the R15<br>release cycle.<br><br></div>I've recently started messing with DTrace on Erlang/OTP in the context of<br>RabbitMQ performance and am very interested in learning more about what<br>you're doing.<br><div style="margin-left: 40px;"><br>I'll be speaking about this DTrace work at the Erlang User Conference in<br>Stockholm, Sweden on Thursday, November 4th. If you're going to be at<br>the EUC and you're interested in DTrace, I'd love to talk to you. If<br>you have a war story about RabbitMQ that you'd like me to share at the<br>EUC (perhaps as part of my presentation), please contact me directly.<br>FWIW, I'll also be attending the tutorial & hack-a-thon day on Friday<br>05 November.<br><br></div>Alas, I'm in North America and won't be there... will your presentation be <br>recorded and put on the web afterward? <br><br><div style="margin-left: 40px;">If you like DTrace but you're not going to be at EUC, then ... I'd like<br>to start some email correspondence. Specifically, what do you need to<br>make RabbitMQ's workings visible to the outside world via DTrace?<br><br></div>Great... I've just recently returned to the perf stuff after some product launch<br>related turbulence that had vacuumed my attention entirely away from it. I'm <br>currently messing around with the OTP fork that's on Github and trying to get<br>a sense for what the existing family of probes can tell me about Rabbit behavior.<br>I'm also sort of learning how to use DTrace in a grown-up manner as I go, so<br>it's likely that my intuition for what is possible and what should be attempted <br>is very poorly honed at this point.<br><div style="margin-left: 40px;"><br>If we actually meet our goal of getting the probes + NIF into the<br>official R15 source distribution ... then the evolution of the probes<br>will probably be slow. Why? Because it'll be tied to Ericsson's<br>release schedule. The more input we get from users of *real* apps<br>(RabbitMQ, Riak, Ejabberd, et al.) now, the better the initial probes<br>will be, and the fewer iterations it will take to make them "perfect".<br><br></div>Are you up for phone or Skype chat on this sometime in the next week or so?<br>I'd be curious to learn more about the probe wish lists for non-Rabbit apps is, <br>assuming that picture has started to come together?<br><br><div style="margin-left: 40px;">In addition, I've added a NIF that allows Erlang code to trigger a<br>
probe. See the EDoc comments at the top of this source file for some<br>
background:<br><br>
https://github.com/slfritchie/otp/blob/dtrace-experiment+michal2/lib/dtrace/src/dtrace.erl<br></div>
<br>
Ah this piece looks very interesting...<br>
<br>Jerry<br><br></div></div></body></html>