Re: [Sablevm-developer] profiling SableVM?

[Chris P. <chr...@ma...>]

Chris Pickett wrote:
> Hi,
> 
> Has anybody had any luck with profiling SableVM?  I need to do this to 
> cut down on the overhead of my speculative multithreading work, because 
> currently benchmarks take too long to execute for an efficient 
> write-compile-test-debug cycle.

So, after more trying with gprof, OProfile, and FunctionCheck ... I 
spoke to Clark, and he soon found qprof, released under the GPL by HP 
(Google finds different things for different people).

It works great!  Even with just a simple install, I get:

$ qprof_start
$ sablevm-chris-switch-spmt-debug -Y DmdNoStrings random2000.dg

Number of components: 399
qprof: 
/home/research/ccl/cpicke/temp/bin/sablevm-chris-switch-spmt-debug: 5710 
samples, 5710 counts
[0x4000dea4]                                        2      (  0%)
libsablevm.so.1                                     286    (  5%)
libsablevm.so.1(_svmf_buffer_create)                2      (  0%)
libsablevm.so.1(_svmf_buffer_validate)              40     (  1%)
libsablevm.so.1(_svmf_buffer_commit)                51     (  1%)
libsablevm.so.1(_svmf_buffer_destroy)               4      (  0%)
libsablevm.so.1(_svmf_buffer_status_ok)             1      (  0%)
libsablevm.so.1(_svmf_predictor_read_jint)          2      (  0%)
libsablevm.so.1(_svmf_predictor_write_jint)         29     (  1%)
libpthread.so.0(__pthread_mutex_trylock)            8      (  0%)
libpthread.so.0(__pthread_mutex_lock)               4      (  0%)
libpthread.so.0(__pthread_mutex_unlock)             40     (  1%)
libc.so.6(malloc)                                   127    (  2%)
libc.so.6(__libc_free)                              29     (  1%)
libc.so.6(calloc)                                   17     (  0%)
libc.so.6(__default_morecore)                       4      (  0%)
libc.so.6(strncpy)                                  1      (  0%)
libc.so.6(memset)                                   117    (  2%)
libc.so.6(memcpy)                                   4804   ( 84%)
libc.so.6(__open)                                   3      (  0%)
libc.so.6(brk)                                      136    (  2%)
libc.so.6(sbrk)                                     3      (  0%)

$ qprof_stop

Which is just the kind of thing I was looking for!

(this is with qprof-0.5 and libunwind-0.96, both available from HP -- 
you need to put a symlink to or extract libunwind-0.96 in the qprof-0.5 
directory for qprof's make to enable libunwind functionality)

I am pretty sure I can get more detailed info if I set things up; I'm 
just sending this mail to report that we have a usable C profiler now.

Cheers,
Chris