> > 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).
You mean, that for each dirty buffer that is reused, the reusing backend fsyncs
the xlog before writing the buffer to disk ?
Andreas