[ltt-dev] [RFC UST] Processes model

[David Goulet]

On 11-01-17 05:15 PM, Mathieu Desnoyers wrote:
>> Single user:
>>
>> +--------+              +------+        +-------+
>> | user A |---- new ---->| ustd |<------>| app_1 |
>> +--------+              +------+        +-------+
>>                            |  |              | write
>>                         fork  create         v
>>    +-----------------+     |  |          +--------+
>>    | ust-consumerd A |<----+  +--------->| shared |
>>    +-----------------+                   | memory |
>>            ^                             +--------+
>>            |                                 |
>>            +-------------- read -------------+
>>
>
> Why should ustd fork the ust-consumerd ?
>
> Also, we will need to represent the pipe communication between ust-consumerd and
> ustd. It is needed to control the buffer access (get/put subbuffer operations).
> If we use a named pipe for this, the access rights will probably need to be
> u+rw and g+rw (write access for group tracing too, to send commands).
>

Agree.

I'm curious about your thought on Nils implementation since it is quite 
different. I surely agree with him on the scaling part and thus having 
only one ust-consumerd...

Cheers

-- 
David Goulet
LTTng project, DORSAL Lab.

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