> Before commit or rollback the xlog is not flushed to disk, thus you can loose
> those xlog entries, but the index page might already be on disk because of
> LRU buffer reuse, no ?
No. Buffer page is written to disk *only after corresponding records are flushed
to log* (WAL means Write-Ahead-Log - write log before modifying data pages).
> Another example would be a btree reorg, like adding a level, that is partway
> through before a crash.
And this is what I hopefully fixed recently with btree runtime recovery.
Vadim
