John, Chris is transferring on average about 360 (2.6M / 2 / 3600) records per second. If the records are ~200 chars, then he's getting about 700kb/sec (that's kb, not kB), or about 1.5% of the throughput you might hope for on a 100Mbps Ethernet pipe! So I'd say Chris does have an issue here.
I can see how increasing the block size would make the network traffic less inefficient, it would be interesting to see what percent busy the network card reports. One of the other issues can be that the data contains, on the UV side, complicated I-Type Dictionary items that mean that the exported data isn't nearly as simple as it looks. This can cause an unexpectedly large amount of I/O on the UV side. Mike -----Original Message----- From: [EMAIL PROTECTED] On Behalf Of John Hester Sent: Friday, 11 August 2006 08:39 To: u2-users@listserver.u2ug.org Subject: RE: [U2] Universe ODBC driver performance issues > -----Original Message----- > From: [EMAIL PROTECTED] Behalf Of Chris Brooks > Sent: Thursday, August 10, 2006 8:21 AM > To: u2-users@listserver.u2ug.org > Subject: [U2] Universe ODBC driver performance issues > > I am new to the group and to UniVerse. We are experiencing issues in > UniVerse 10.1.3 downloading data via the ODBC connection to SQL > Server. > 2.6 mil records can take 2 hours to complete. We are currently using > the default settings for the ODBC driver. I will soon make changes to > increase the prefetch and threshold values. Any experience with the > ideal settings? From my testing the best performance seems to be at > prefetch = 16383 and threshold = 4096 on the ODBC driver. At this > settings seem to get a 30% performance increase. I would like to see > it improve even more. > > > During the download the CPU is utilized less than 10%. Sounds like you're I/O bound, although 2.6 million records in 2 hours isn't all that bad in my experience. Is it possible you're hitting the threshold of your NICs, or competing with a lot of other network traffic? If both machines have multiple NICs, you could reserve one on each machine for only talking to the other. You could add an entry to the hosts file on each so it would only know the other machine by the reserved NIC's IP, then just make sure the reserved IP addresses don't exist in DNS so no other machines will use them. If the machines are physically close, a crossover cable from NIC to NIC would eliminate any switch performance issues. At that point a rough calculation of your throughput based on the average size of each record would tell you if you're utilizing the available bandwidth, or if there's some other bottleneck. -John ------- u2-users mailing list u2-users@listserver.u2ug.org To unsubscribe please visit http://listserver.u2ug.org/ The information contained in this Internet Email message is intended for the addressee only and may contain privileged information, but not necessarily the official views or opinions of the New Zealand Defence Force. If you are not the intended recipient you must not use, disclose, copy or distribute this message or the information in it. If you have received this message in error, please Email or telephone the sender immediately. ------- u2-users mailing list u2-users@listserver.u2ug.org To unsubscribe please visit http://listserver.u2ug.org/
