sql server doesn"t work well with 250ms+ network latency

Hello,

I'm an absolute newbie when it comes to SQL. I was told that SQL
server does not function well on a WAN where network latency between,
say, the SQL server and a front-end server is greater than 250ms.

I can't find anything information supporting this claim online, so I
was hoping someone here could tell me if this is true or not?

Thank You!!

Re: sql server doesn"t work well with 250ms+ network latency

(jeff80@gmail.com) writes:
> I'm an absolute newbie when it comes to SQL. I was told that SQL
> server does not function well on a WAN where network latency between,
> say, the SQL server and a front-end server is greater than 250ms.
>
> I can't find anything information supporting this claim online, so I
> was hoping someone here could tell me if this is true or not?

Of course, it helps if client and server are on a fast connection.
But it also depends on a lot of the application and how it is designed.
An application which does not retrieve huge amounts of data, and which
is well-written and not perform a lot of network roundtrips can perform
decently over a slower connection as well.

So there is no definitive answer to the question.


--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

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Re: sql server doesn"t work well with 250ms+ network latency

> I'm an absolute newbie when it comes to SQL. I was told that SQL
> server does not function well on a WAN where network latency between,
> say, the SQL server and a front-end server is greater than 250ms.
>

Depends what you are doing, database mirroring in full safety would be out
:) and yes, network latency in database mirroring is crucially important.

Replication is another area where you'd see lots of posts if network latency
where a problem, check out this MS article:
http://blogs.msdn.com/sqlcat/archive/2007/05/07/sql-server-2 005-transactional-replication-benefit-of-using-subscriptions treams-for-low-bandwidth-high-latency-environments.aspx

Tony

--
Tony Rogerson, SQL Server MVP
http://sqlblogcasts.com/blogs/tonyrogerson
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