Ruby 2.6.5 with jemalloc

Question

I've built and installed rub 2.6.5 from source with jemalloc. However when I check to see if its there I'm not seeing an entry. Is there something else I should have been doing?

ubuntu:~$ uname -a
Linux ip-10-0-3-198 4.15.0-1032-aws #34-Ubuntu SMP Thu Jan 17 15:18:09 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
ubuntu:~$ ./configure --enable-shared --with-jemalloc
ubuntu:~$ make
ubuntu:~$ make install

Which results in:

ubuntu:~$ ruby -r rbconfig -e "puts RbConfig::CONFIG['LIBS']"
-lm 

Tracking memory usage once deployed I'm also not seeing a drop compared to similarly configured servers without jemalloc in place.

I'm not sure what I need to be doing in order to get jemalloc working.

Thanks!

Answer 1

For some reason, the accepted answer does not work for me (Heroku), but this:

MALLOC_CONF=stats_print:true ruby -e "exit"

has done the trick.

If you have some stats ouput, means it's working.

source: https://github.com/gaffneyc/heroku-buildpack-jemalloc/issues/5#issuecomment-499932026