One of my clients is running FMS on Windows 2003 Server on a maxed out box that is extremely fined tuned. I rarely see the processors over 7%, although at times one of the 8 cores maxes out. The same goes for memory and networking. Although network usage does see more use. Disk usage is active, but I’m running on RAID 10 with 15K disks and backups are done on a RAM disk which an OS script then passes the backups off to an entirely separate hard drive system. In my opinion, FileMaker does not do a good job taking advantage of multiple processors.
It’s all about how FMS queues requests on specific files and one unindexed search, or something else that takes processing power like running a report with unindexed calculations, can bog down an entire group of users. If a particular file is extremely active and you run an unindexed search, that file is handed off to a single core to process one task at a time. You can just imagine what can happen here if you’re at the end of a long queue. I cannot remember if it’s one file or one table within a file and I have not done enough testing here to confirm. But, this is why in a system with multiple modules (and files for each), a solution may “seem” slow in one area, but not in others.
Even a table with hundreds of fields is much better split into smaller tables each with fewer fields since server passes all data in all fields from a single table over to the client when the client has to process certain requests. This can be another major bottleneck.