Hello Sven,
I confirm that it is a very good way to profile ...
Here are some tricks we are using:
1) You can profile only some parts of your code with
============================
(include "valgrind/callgrind.h")
(define (start-profile)
(pragma::void "CALLGRIND_START_INSTRUMENTATION;")
#t)
(define (end-profile)
(pragma::void "CALLGRIND_STOP_INSTRUMENTATION; CALLGRIND_DUMP_STATS;")
#t)
============================
Then launch your app with valgrind --tool=callgrind --instr-atstart=no
2) References to Scheme code
When profiling, we use the -rm Bigloo option to keep C code.
In kcachegrind when clicking at "Source code" it goes in the C code where
there is, in comments, Line numbers of your scheme code.
It is particulary helpful when you arrive to "anonymous" functions ....
3) Demangle valgrind output:
We also use this little function in order to demangle valgrind output:
============================
(define (prof-demangle filename)
(let ((temp-filename (format "~a.demangle" filename)))
(with-output-to-file temp-filename
(lambda ()
(with-input-from-file filename
(lambda ()
(let loop ((line (read-line (current-input-port))))
(if (not (eof-object? line))
(let ((func (pregexp-match "BG[lL]_[\\w_]+z\\w\\d$"
line))
(func-quote (pregexp-match "BG[lL]_[\\w_]+z\\w\\d'2$"
line)))
(cond
(func (let* ((bigloo-func (bigloo-demangle (car
func))))
(print (pregexp-replace "BG[lL]_[\\w_]+z\\w\\d$"
line
bigloo-func))))
(func-quote (let* ((bigloo-func (bigloo-demangle
(substring (car func-quote) 0 (- (string-length (car func-quote)) 2)))))
(print (pregexp-replace
"BG[lL]_[\\w_]+z\\w\\d'2$"
line
(format "~a'2"
bigloo-func)))))
(else (print line)))
(loop (read-line (current-input-port))))))))))))
============================
Have a nice profiling session !
( Thanks to Kevin in hour team that suggest kcachegrind and made the demangling
function! )
BR,
Pierre-Francois
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of
Sven Hartrumpf
Sent: Monday, February 3, 2020 12:40 PM
To: [email protected]
Subject: [bigloo] Using valgrind for profiling bigloo-compiled binaries
Hi Bigloo users.
I just want to share a positive experience with valgrind (version 3.15) for
profiling bigloo-compiled binaries. Here is a step-by-step guide:
1 Compile your binary with debug options (-g2); my binary name is foo.
2 Run your binary; you can stop it when you collected enough data:
valgrind --tool=callgrind foo <foo-option1> ...
3 Browse the profile results:
kcachegrind callgrind.out.*
Advantages over bglprof:
- The bigloo installation need not be configured for profiling.
- No special compilation of your binary needed (except for -g2).
- Accurate statistics (With bglprof, I sometimes see attributions
to wrong functions - which might be my fault.)
- The host where you run your profiled binary needs no matching
bigloo installation, if the binary is linked statically.
Disadvantages:
- Your binary will run 10-100 times slower than normal.
- Names of Scheme functions are mangled.
Ciao
Sven
