[racket-dev] [racket] Profiling mostly macro-generated definitions?

On Wed, Aug 29, 2012 at 5:26 AM, Antonio Leitao <aml at gia.ist.utl.pt> wrote:
> On Tue, Aug 28, 2012 at 7:17 PM, Robby Findler
> <robby at eecs.northwestern.edu> wrote:
>> Well, here's an example of it working. I don't know what to suggest
>> but to ask if you could make a small program that illustrates it not
>> working and maybe we can go from there to understand why you're seeing
>> what you're seeing.
>>
>> #lang racket
>> (require profile)
>>
>> (define h (make-hash))
>> (profile
>>  (let loop ([n 1000000])
>>    (unless (zero? n)
>>      (hash-set! h n #t)
>>      (hash-ref h n)
>>      (loop (- n 1)))))
>
> This exact program, in DrRacket 5.3 (Windows 64 bits)
> only shows
>
> Welcome to DrRacket, version 5.3 [3m].
> Language: racket; memory limit: 1024 MB.
> Profiling results
> -----------------
>   Total cpu time observed: 904ms (out of 905ms)
>   Number of samples taken: 11 (once every 82ms)
>
> ====================================
>                         Caller
> Idx  Total    Self    Name+srcLocal%
>      ms(pct)  ms(pct)   Callee
> ====================================
>>
>
> Increasing the loop to 10000000 iterations shows:
>
> Welcome to DrRacket, version 5.3 [3m].
> Language: racket; memory limit: 1024 MB.
> Profiling results
> -----------------
>   Total cpu time observed: 8464ms (out of 8549ms)
>   Number of samples taken: 116 (once every 73ms)
>
> ====================================
>                         Caller
> Idx  Total    Self    Name+srcLocal%
>      ms(pct)  ms(pct)   Callee
> ====================================
>>
>
> Is this happening because I'm running the code in
> DrRacket?

(I've re-added dev; hope that's okay.)

No, that shouldn't be the cause.

I'm forgetting now when this is triggered, but I recall that on some
platforms, or with some ways the installation is configured, stack
traces can be disabled (which would render the profiler useless, as
that's how it figures out what is going on). Probably this is what
you're seeing.

FWIW, the version of Windows I use is Windows 7 and I see good output
using version 5.3, the latest nightly build, and a version I just
build myself (I checked the nightly and the release just to see if
there were different configuration options used.)

I believe I'm using the 32 bit build in all those cases, tho. Are you
using the 64 bit one?

Robby