> The problem is we can't reliably differentiate commit-in-progress from > a corrupt first commit...
I think you can tell them apart with high probability because the checksum is off by exactly one(at least in lucene 3.5 where I'm looking). It does seem dangerous to rely on an implementation detail of the pre-commit like this, though. Is there a reason lucene couldn't write a "isCommitted" byte to segments_n and use this byte to detect pre-committed segments reliably? Cheers, Geoff