Re: Implementing a generic binary trace interface.

["Jose R. Santos" <jrs at us dot ibm dot com>]

Frank Ch. Eigler wrote:

> Hi -
>
> > [...] One of simpler ways, I think, is to allow the script functions
> > to take long arrays as its arguments. Thus, we can transport whole
> > the array to user space as like below;
> >
> > function array_log ( map:long[] ) %{
> > [...]
> > %}
>
> Can you think of a scenario where tracing an entire array could be
> necessary in a time-critical place?  If not, then coding the array
> printing by an explicit foreach would not be a serious burden.
>
> - FChE
>
>  
Its not really a problem if you are only planning on having a single 
trace point.  The problem is that as you add more trace hooks little 
burdens start adding up.  Some of the uses that we have for our trace 
tool require multiple hooks working together.  If running a trace 
impacts the performance to much, that impact may change some of the 
performance characteristics of the workload making the trace useless.

-JRS