Обсуждение: Network performance optimization

Hi Team, I am performing some benchmark testing with application in aws east 2 and dB in East 1. I am using pgbench for benchmark, the RTT Latency between East 1 to east2 is some where between 12 to 16 ms on an average. Is there any optimization that can be done to reduce the latency and increase the throughout to the PostgreSQL layer?

On 09/09/2020 04:59, J . Mageshwaran wrote:
> Hi Team, I am performing some benchmark testing with application in aws 
> east 2 and dB in East 1. I am using pgbench for benchmark, the RTT 
> Latency between East 1 to east2 is some where between 12 to 16 ms on an 
> average. Is there any optimization that can be done to reduce the 
> latency and increase the throughout to the PostgreSQL layer?

Even if network datagrams moved at the speed of light and with no 
serialisation/forwarding delay (which they don't), you're still going to 
deal with several thousand KMs of distance; I'm positively surprised 
you're getting such short round-trip times as it stands.


If you have any control over the application code, IMO your best shot is 
to coalesce DB interactions into as few smarter DB queries as you can 
for each higher order operation (eg: RESTful API calls), as you'll be 
paying for that fixed RTT overhead for each command.




-- 
Regards

Fabio Ugo Venchiarutti
OSPCFC Network Engineering Dpt.
Ocado Technology

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Fabio:

On Wed, Sep 9, 2020 at 1:05 PM Fabio Ugo Venchiarutti
<f.venchiarutti@ocado.com> wrote:
> Even if network datagrams moved at the speed of light and with no
> serialisation/forwarding delay (which they don't), you're still going to
> deal with several thousand KMs of distance; I'm positively surprised
> you're getting such short round-trip times as it stands.

Light travels at about a foot per nanosecond in air/vacuum, 20 cm per
nanosecond in glass IIRC, so you can RTT 10cm per nanosecond in fiber.
This amounts to 100km per millisecond. 1200 to 1600 km in 12-16 ms.
East-1/2 are N.Virginia / Ohio, which can be from 240 to 950 km apart
( on a quick google maps measure, not several thousands ), depending
on the exact place. And Amazon has really fast pipes going between
their regions, so this is not surprising. I have 55ms from ireland (eu
west 1) to N.Virg., and they are 5500 km over the great circle.

Francisco Olarte.