Zdenek Kotala wrote:
> Tom Lane napsal(a):
>> I see no value in cluttering the system with useless probes. The worker
>> start/stop are the only ones here with any conceivable application IMHO.
>
> As I answered to Alvaro. I needed to catch start of backend several times
> to track call flow or attach debugger. It is possible to use some other
> dtrace magic for that, but it is not easy and there is not way how to
> determine what kind of process it is. For example how to measure how
> many writes performs bgwriter?
If you need to attach a debugger to a backend, you can use the -W switch
(even on PGOPTIONS if you need it for a particular backend, AFAIR). If
you want to "truss" it I guess you can use -W too.
Does it have any usefulness beyond that?
--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.