compatibility with apps using mallopt?

Eric Wong normalperson at
Sun Nov 17 14:47:33 PST 2013

Hi, I'd like to continue providing the option of using jemalloc (and
other alternative malloc implementations) to glibc/Linux users of

I have a pending change[2] in cmogstored.git which adds mallopt(3)
support.  This needed for good out-of-the-box VM usage on modern glibc
and many disk-bound threads.  cmogstored is not at all dependent on
malloc performance/scalability, so glibc malloc defaults clash greatly
with the design of cmogstored.

When I ./configure with LIBS=-ljemalloc, things go bad because the
mallopt call is still detected and going to glibc even though the glibc
malloc implementation is not used/linked.

So my question is: what's the best way to avoid mallopt() when using
glibc if cmogstored is linked to jemalloc (or any non-glibc malloc)?

Or should jemalloc provide a mallopt() function which may
wrap mallctl() in some cases and/or just do nothing at all?

Thanks for reading.

[1] -
[2] -

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