The sysctl option “kernel.core_uses_pid” comes into play when a vmcore file is being dumped. It can be set in one of two ways;
kernel.core_uses_pid = 0 or kernel.core_uses_pid = 1
As you can probably tell this is a binary settings. It’s either enabled (1) or it’s not (0).
The exact text from the sysctl.txt file is;
============================================================== core_uses_pid: The default coredump filename is "core". By setting core_uses_pid to 1, the coredump filename becomes core.PID. If core_pattern does not include "%p" (default does not) and core_uses_pid is set, then .PID will be appended to the filename. ==============================================================
For Fedora 22 this parameter is set to “1” by default.