In the rare case of a Dgraph crash, the Dgraph writes its core dump files on disk.
When the Dgraph runs on a very large data set, the size of its index files stored in-memory may exceed the size of the physical RAM. If such a Dgraph process fails, it may need to write out potentially very large core dump files on disk. The core files are written to the Endeca Server's logs directory.
To troubleshoot the Dgraph, it is often useful to preserve the entire set of core files written out as a result of such failures. When there is not enough disk space, only a portion of the files is written to disk until this process stops. Since the most valuable troubleshooting information is contained in the last portion of core files, to make these files meaningful for troubleshooting purposes, it is important to provision enough disk space to capture the files in their entirety.
Keep in mind that the Endeca Server attempts to restart the Dgraph node when it crashes. If the start-up retry fails, the Endeca Server will retry the start-up only one more time.