Re: Network throughput limited to 1/25 th network capacity

Andreas Sheriff wrote:
> Hi,
>
> I'm connecting to an Oracle 8i database tunneled through ssh connecting
> across the internet and the data transfer rate is consistently slow. The
> rate is approximately 1/25th of the lowest upstream/downstream common
> denominator (512k DSL upstream). I know it's not the tunneling that's
> slowing it down, nor is it the connection via SSH, but the connection that
> Oracle makes itself. The database was hosted in the local network before
> (100Bt) and the transfer rate never got above 4mbps (1/25 X 100 mbps). I've
> even tried it through my 802.11g wireless connection to the local network
> and the transfer rate never got above 2.2 mbps ( 1/25 X 54 mbsp).
> The connection is configured to use TCP.
> Can anyone tell me what's going on and how to optimize the Oracle TCP
> connection so that it will be faster?
>
> Thanks,
> Andreas
>

Not sufficient information to conclude it is an Oracle Net problem alone. Try connecting using TCP locally on the same server as the database (to eliminate the physical components of your network) and see if you can reproduce the problem.

Check for packet errors, mis-matched duplex settings on your host and switch interfaces, and so on. Test simpler types of data transfers, such as FTP with a large file. SSH overhead for encryption/decryption can indeed become the bottleneck if the CPU is already overloaded with other work, although that doesn't sound like the sole culprit in your case. Something as basic as a bad cable can cause problems just like this.

How are you measuring the transfer rate?

-Mark Bole Received on Fri Mar 04 2005 - 15:10:14 CST