I've been searching for similar questions, but couldn't find any useful, sorry if duplicate. (I read windows 2003 server slow access and Horrible Windows Server 2003 performance while copying files through Netbios)
We've got a ML 115 G5 server with Windows 2003 32bit. It acts as file server, LAMP server and Trend Micro Office Scan server. It also has an old MSDOS program.
It's less than 2 years old. In the 100mbps network there are only two clients. One of them uses more often the MSDOS problem, and the LAMP server, which run more or less OK. The problem is with the other client. She opens Office documents and this is where the server comes to a worrying slow speed.
We run an HD Tune test, and we found 28ms of latency and slow transfer ratio. We updated to the latest NVidia Raid software driver (RAID1, by the way), and it improved just a little. We went down to 23ms of latency and better transfer ratio, but still low.
It's not a matter of the switch, as it is slow even with a direct crossed cable connection. Tried with small files and a big iso file.
Tried also disabling antivirus client, as most of the hard disk IO was Trend Micro related, but still the same.
Windows is fully updated, as well as the network card drivers. Memory is less than 50% occupied, and none of the 4 CPU reach 20% of proccessing.
My main question is, what can I look at or where can I search to find the bottleneck?