The problem is that SQL*Net is too chatty, because FTP runs fine.

  • From: "David Taft" <oradbt054@xxxxxxxxx>
  • To: oracle-l <oracle-l@xxxxxxxxxxxxx>
  • Date: Thu, 31 Jan 2008 12:14:43 -0500

Platform: Oracle 10gR2 on AIX 5L

We have a materialized view refresh that takes just ten minutes to complete
between a database in the US-southwest and one on the east coast.  That same
refresh between a database in the southeast and the east coast database
takes 3 hours to complete.  All settings like SDU, SEND_BUF_SIZE and
REC_BUF_SIZE have been verified as being set the same and the network group
tells us that we are only using half the bandwidth on that southeast to east
WAN pipe, so our next thought was that the problem is network latency
between the  southeast and east coast data centers.  However, the group
managing that WAN connection claims the problem is that the application (i.e.
SQL*Net) is too chatty because FTP works fine.  Yes, SQL*Net is chatty.  It
has always been chatty and always will be chatty. Comparing FTP to SQL*Net
chattiness seems an unfair comparison, but I find that some network
engineers like to say that "SQL*Net is just too chatty."  Unfortunately this
does nothing to help me solve the problem.

I am curious how others have addressed this issue in a way that doesn't make
the network group defensive, but rather gets them to understand that a WAN
designed for FTP does not necessarily work fine for Oracle?  Are there any
test scenarios that effectively demonstrate this in a way that a network
engineer can appreciate?  Also, if you know of any white-papers that address
this issue that would be great also. I tried googling around, but must not
have hit the right keywords, because I didn't find anything I could use.

Thanks & Cheers,


P.S. The east-southeast WAN pipe is new, where the east-southwest pipe is a
long-time established connection.  Each is managed by a different network
group in different organizations.

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