2 karma · joined January 25, 2010
My sense has been that at least the low end of the market is increasingly preferring a search-oriented log management architecture versus a database-backed, query-heavy architecture because organizations are familiar with the search metaphor, the overhead of managing a search index is less than the cost of database administration, and the unsophisticated use case (i.e., free-text search rather than advanced query syntax) is increasingly common. Smaller organizations also rarely have the maturity to deal with logging systematically since it requires a pretty systematic approach to infrastructure. That said, the tradeoffs we made may or may not apply in a terabytes-per-day environment, I unfortunately can't speak to it directly.
All that said, good luck in your endeavors!
Unfortunately, I don't work in a TB/day environment (though that would be fun), so I can't comment on that directly, but our experience with Splunk has been positive at this scale and I see no reason so far why a distributed installation with multiple 100GB/day nodes would change that. The only customer complaints we have are basically that long-term searches don't return instantly, and that's primarily a factor of I/O speed and can be resolved by setting up summary indexing (which requires forethought about what data you're interested in... therefore, it very rarely happens in my organization).