My macbook pro (mid-2010 running 10.9.5) has been crashing a lot lately. I haven't made any changes to it (either hardware or software) or installed anything new but it seems to be something to do with a kernel process "mdworker".
After each crash and when I log in again spotlight starts indexing immediately. This further causes temperatures to rise about 90 degrees and usually the macbook pro will then go into a cycle of crashes.
It seems to be all due to spotlight indexing.