[rabbitmq-discuss] DTrace and Erlang: an update

[Scott Lystig Fritchie]

Jerry Kuch <jerryk at vmware.com> wrote:

> Alas, I'm in North America and won't be there... will your presentation be
> recorded and put on the web 

I'm assuming that the recording will be made available eventually on
the Erlang Factory webathingie, like the slide and video links (icons
only, look for the camera icon & the easel icons) at
https://www.erlang-factory.com/conference/London2011/talks

>> https://github.com/slfritchie/otp/blob/dtrace-experiment+michal2/lib/dtrace/src/dtrace.erl
>
> Ah this piece looks very interesting...

It's an attempt to create a multi-purpose function.  The normal way
of creating new USDT probes is to run through the standard C
compiler +DTrace cycle to create a new shared library.  Not really
feasible for most app deployments.  The dtrace:p/1 function is
an attempt to create a flexible multi-blade pocket knife single
function, rather than create a function for 1 int and 1 string, 1 int
and 2 strings, 0 ints and 3 strings, etc.

However, it *is* possible to create new DTrace probes by talking
directly to the /dev/dtrace* directly.  There's code in the Node.js
repo to do exactly that, see
https://github.com/chrisa/node-dtrace-provider.  Porting that code
(if the license is agreeable) to the Erlang project would be a very
handy thing.

-Scott