Re: Broken stuff in new dtrace probes - Mailing list pgsql-hackers

From Robert Lor
Subject Re: Broken stuff in new dtrace probes
Date
Msg-id 49C95365.6030000@sun.com
Whole thread Raw
In response to Re: Broken stuff in new dtrace probes  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane wrote:
> Greg Stark <stark@enterprisedb.com> writes:
>   
>> i like the idea of just have a separate pair of probes for table
>> extension. I bet there are people who would actually like to see that
>> alone sometimes too.
>>     
>
> After further thought I concluded that the best solution for this is to
> add the isExtend flag to the buffer_read_start/read_done probe parameter
> lists.  This allows the dtrace script writer to make the distinction if
> he chooses, without adding any extra overhead for normal non-traced
> operation.  AFAICS using a separate probe type would add at least a
> couple of if-tests even with tracing turned off.
>   
I like this solution.  From my perspective, it's always better to give 
the script writer the flexibility to pick and choose the data s/she 
wants to see and at the same time avoid adding new probes unnecessarily.

-Robert


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