Crash dump files are empty

Hey, whenever my dedicated garry’s mod server crashes (crashes are very random), it says that crash dump has been saved to /tmp/dumps, however those crash dump files are empty, filesize 0 bytes. Does anyone have any idea why? I could use some advice.

Server OS: Ubuntu Server 12.04 LTS
Processor: AMD PHENOM II X4 960T 3.0G
Ram: 8gb
Game(s): Garry’s mod and CSS for content
Start Up Command: ./srcds_run -console -game garrysmod +maxplayers 21 +map dm_island18_night -autoupdate
Admin Mods: ULX + Sourcemod

Hmm, my mysteri still remains unsolved.

If I add -debug to launch script, it will create debug.log whenever my server crashes, is it same as crash dump?