[erlang-bugs] Trace bug?

[Robert Virding]

No, answers?

Robert



On 30 May 2014 23:18, Robert Virding <rvirding@REDACTED> wrote:

> Can anyone tell me if this is a bug? If not how do I get around it in
> simple way?
>
> Robert
>
>
>
> On 27 May 2014 17:45, Robert Virding <rvirding@REDACTED> wrote:
>
>> We have discovered strange behaviour when tracing message sends. We turn
>> on tracing message send for a process. In R16 and 17 it seems like there is
>> no trace message when sending to a registered process name, while sending
>> to a pid generates a trace message as it should. In R15 however you get a
>> trace message both sending to a registered name and hen sending to a pid.
>> Is this a bug or is it a new undocumented feature?
>>
>> As an example I include simple program in which worker sends a message to
>> a registered server and the server replies by sending the worker pid. Here
>> are outputs when running in 17:
>>
>> Erlang/OTP 17 [erts-6.0] [source-07b8f44] [64-bit] [smp:4:4]
>> [async-threads:10] [hipe] [kernel-poll:false] [dtrace]
>>
>> Eshell V6.0  (abort with ^G)
>> 1> c(trace_procs).
>> {ok,trace_procs}
>> 2> trace_procs:start().
>> trace_procs 7 Server: '<0.39.0>'
>> trace_procs 10 Worker: '<0.40.0>'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,answer,<0.40.0>}'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,answer,<0.40.0>}'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,answer,<0.40.0>}'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,answer,<0.40.0>}'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,answer,<0.40.0>}'
>>
>> and in R15:
>>
>> Erlang R15B03 (erts-5.9.3.1) [source] [64-bit] [smp:4:4]
>> [async-threads:0] [hipe] [kernel-poll:false]
>>
>> Eshell V5.9.3.1  (abort with ^G)
>> 1> c(trace_procs).
>> {ok,trace_procs}
>> 2> trace_procs:start().
>> trace_procs 7 Server: '<0.38.0>'
>> trace_procs 10 Worker: '<0.39.0>'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,{request,<0.39.0>},server}'
>> trace_procs 34 Message: '{trace,<0.38.0>,send,answer,<0.39.0>}'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,{request,<0.39.0>},server}'
>> trace_procs 34 Message: '{trace,<0.38.0>,send,answer,<0.39.0>}'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,{request,<0.39.0>},server}'
>> trace_procs 34 Message: '{trace,<0.38.0>,send,answer,<0.39.0>}'
>> trace_procs 34 Message: '{trace,<0.39.0>,send,{request,<0.39.0>},server}'
>>
>> What gives?
>>
>> Robert
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://erlang.org/pipermail/erlang-bugs/attachments/20140602/941e8d65/attachment.htm>