This happens on either AMD or Intel nodes in our cluster. On our 128-core nodes, parpool(128) fails with an nproc limit at 32,768.
Our systems architect figured this out. It turns out that Matlab was seg faulting on the default nproc limit (max number of user processes), which is set by default to 4,096.
The issue is with the /etc/security/limits.d/20-nproc.conf provided by the PAM RPM on CentOS 7, which limits every user to 4096 processes at once. But not for Matlab.
>> parpool('local', 46)
Starting parallel pool (parpool) using the 'local' profile ...
*** Error in `/share/software/user/restricted/matlab/R2020a/bin/glnxa64/MATLAB': double free or corruption (!prev): 0x00007f4e4027d090 ***
*** Error in `/share/software/user/restricted/matlab/R2020a/bin/glnxa64/MATLAB*** Error in `/share/software/user/restricted/matlab/R2020a/bin/glnxa64/MATLAB': free(): corrupted unsorted chunks: 0x00007f4e401e10d0 ***
A bad case of segmentation fault:
[7191121.585896] MATLAB: segfault at 118c0f20 ip 00007fa1cd076b8d sp 00007fa1973fbc60 error 4 in libc-2.17.so[7fa1cd03d000+1c2000]
[7191121.610055] traps: MATLAB general protection ip:7fcb5d0b0b8d sp:7fcb273fbc60 error:0 in libc-2.17.so[7fcb5d077000+1c2000]