> I'm planning on continuing to increase XLOG_BLCKSZ and wal_buffers to
> determine when the throughput starts to level out or drop
I think for an even better comparison you should scale wal_buffers
down with increasing XLOG_BLCKSZ, so that the xlog buffer has a fixed
size in kb.
Reasonable wal_buffers imho amount to at least 256kb, better yet 512 or
1 Mb,
with sufficiently large transactions (and to try to factor out the
difference
between blocksizes).
Andreas