Windows NT Server Hardware Issues
The addition of a second microprocessor to a system will not make it twice as fast. This is due to the operating overhead of managing the processor time slices. The system will be about 50% faster.
Memory is stored in 4 K pages. Each page can only be used by one thread. If an NT server has less than 32M of RAM, significant page swapping may occur. A server operates best with 24 M of RAM or more.
SCSI is terminated with a terminator or at a device. Only the end device should have termination enabled. The SCSI cable should be short.
Disk swapping is set up using the performance tab in the System applet of the control panel. It is only worthwhile to set one swap page file per physical disk. Although a swap file can be added to each partition, this will actually slow the system since the drive heads will be required to move a larger distance more often.
Entire disk clusters are read into RAM at one time. NT uses write back caching where data writes that are waiting in the cache can be read from the cache. Another method is write through caching where writes to disk cache are immediately written to the hard drive.
Disk BIOS Settings
Sector translation is used to allow operating systems with a 1024 cylinder limit to operate on large hard drives. Sector translation can be turned on in the BIOS. Once turned on, this should not be turned off.
Reasonably fast hard drives transfer data at about 2M per second. Computers are moving from peripheral cards of EISA to PCI since PCI cards are faster. If you use a ISA based controller card, you can expect no more than an 8M per second transfer rate from your controller card. some controller types and maximum speeds are:
- IDE - 5 M / sec
- SCSI - 6 M / sec
- SCSI-2 Fast - 10 M / sec
- SCSI-2 Fast and Wide - 20 M / sec
- Ultra DMA IDE - 33M / sec
- Ultra SCSI - 40M / sec