Re: Perf Benchmarking and regression.

On Fri, May 13, 2016 at 7:08 AM, Ashutosh Sharma <ashu.coek88@gmail.com> wrote:
> Following are the performance results for read write test observed with
> different numbers of "backend_flush_after".
>
> 1) backend_flush_after = 256kb (32*8kb), tps = 10841.178815
> 2) backend_flush_after = 512kb (64*8kb), tps = 11098.702707
> 3) backend_flush_after = 1MB (128*8kb), tps = 11434.964545
> 4) backend_flush_after = 2MB (256*8kb), tps = 13477.089417

So even at 2MB we don't come close to recovering all of the lost
performance.  Can you please test these three scenarios?

1. Default settings for *_flush_after
2. backend_flush_after=0, rest defaults
3. backend_flush_after=0, bgwriter_flush_after=0,
wal_writer_flush_after=0, checkpoint_flush_after=0

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company