I've always been surprised that there aren't widely-used tools (I think they do exist but just aren't very popular) that monitor logs and analyze them for irreg

I've always been surprised that there aren't widely-used tools (I think they do exist but just aren't very popular) that monitor logs and analyze them for irregularities. Have it learn what messages are 'normal' and only send up an alarm when something statistically significant crops up. It doesn't even have to be heavy machine-learning, just some basic statistical analysis would probably help a great deal. Add in correlating multiple logs with one another (increasingly an issue when you've got dozens of servers actually running your application, any of which could be raising important messages while all of them clutter the log with usually-unimportant messages). Taking a firehose of data and breaking it down into what needs attention is something software should be much better at than human beings.