Re: database/internet lag?

"jking" <johnking100_at_hotmail.com> wrote in <20010521.094727.1684171494.13463_at_pumpkin.dublin2>:

>Sorry, I wasn't too clear in my earlier posting...
>
>I'm wondering how distance between servers affects database
>replication... I'm assuming typical database replication involves large
>amounts of data, leading to few TCP/IP connections being made, and lots
>of data being sent across each connection. So, would a
>Paris-London replication be much faster than a London-California
>replication??

I believe that you can have a high speed connection (such as 10Mb/s?) both between Paris/London and London/California. Both 10Mb/s connections can transfer the same amount of data per second :-).

The London/California connection may be more expensive. You may want to check what speed you can purchase for a given amount of money for the two routes.

Another thing to look out for is how the replication protocol is written. The roundtrip time (ping time) for a transatlantic connection will probably be much higher than between london/paris. If the protocol does lots of (query-waitforanswer-readanswer-postnextquery) types of transactions, then it might be difficult to saturate a high-speed connection.

-- 
/Per Schröder
http://developer.mimer.com