The stack of one of the threads shows a call to umem_update_thread() implying that libumem is being used. I am not sure if ‘fmd’ by default uses libumem. If not, then were you using libumem to debug a memory related issue (perhaps a memory leak or memory corruption?) The XML manifest file for the fmd service will have information as to how the ‘fmd’ process is launched — LD_PRELOAD is set to libumem and UMEM_DEBUG is set before invoking the ‘fmd’ executable in case libumem is being used. If so, You might want to check the value of UMEM_DEBUG environment variable. Please keep in mind that using the debug features of libumem has a cost overhead in terms of memory (virtual address space and physical memory) used depending on the value of the UMEM_DEBUG variable. Given that there are core files of the ‘fmd’ process in your system, you might want to check if there are any leaks detected by mdb’s ::findleaks dcmd. http://technopark02.blogspot.com/2016/08/solaris-memory-leak-checking-with.html?m=1 You can look at the above website to get informed about how to use mdb’s dcmds to get information about libumem data structures. Hope this helps, Pramod On Mon, 22 Jul 2024 at 19:33, Gabriele Bulfon via illumos-developer < developer@lists.illumos.org> wrote: > Hi, I have a couple of systems, installed in 2012 and updated up to > illumos 2019 (will have to update to 2024 later). > They periodically (every 3-4 months, sometimes earlier) create a core dump > under /var/fm/fmd. > Looks like fmd core dumped, so no email notice is sent, and we end up > filling the rpool. > I found this link: > https://support.oracle.com/knowledge/Sun%20Microsystems/1020519_1.html > So here I attach the pstack of one of the dumps. > > Any idea? > > Gabriele > > > *Sonicle S.r.l. *: http://www.sonicle.com > *Music: *http://www.gabrielebulfon.com > *eXoplanets : *https://gabrielebulfon.bandcamp.com/album/exoplanets > > *illumos * / illumos-developer / see > discussions + participants > + delivery options > Permalink > >