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FINDING AND PREVENTING PROCESSOR BOTTLENECKS
If you're running Internet Information Server (IIS), your system's speed and efficiency depend on the server's processor. IIS code is multithreaded for efficient scaling on single-processor and multiple-processor computers and is largely self-tuning. However, you might run into bottleneck problems on the active server, and even on servers with multiple processors.
A processor bottleneck occurs when one or more processes occupy nearly all the time on a computer's processors. You can have a bottleneck on a multiple-processor computer even when only one processor is exhausted if the system doesn't distribute work in the queue to the other processors. In a bottleneck, the ready threads of processes must wait in a queue for processor time. All other activity stops until the queue clears. You can't fix a bottleneck by adding or improving other computer components (e.g., memory, disks, network connections).
To determine whether you're experiencing a processor bottleneck, refer to the following Performance Monitor counters:
- Process: % Processor Time—Processor use attributable to each processor.
- Processor: % Processor Time—Processor use on each processor. This counter reveals unequal distribution of processor load.
- Processor: % Privileged Time—Proportion of the processor's time spent in privileged mode. In Windows NT, only privileged mode code has direct access to hardware and to all memory in the system. The NT Executive runs in privileged mode. Application threads can switch to privileged mode to run OS services.
- Processor: % User Time—Proportion of the processor's time spent in user mode. User mode is the processor mode in which applications, such as IIS services, run.
- System: % Total Processor Time—The sum of processor use on each processor, divided by the number of processors.
- System: Processor Queue Length—Number of threads waiting for processor time. If this value exceeds 2 for a sustained period of time, the processor might have a bottleneck.
—Tommy Gustafsson
Tommy.Gustafsson@eng.ericsson.se
HANDLING FILE PROPERTIES
I still use File Manager (winfile.exe) to manage the files on my system. I prefer File Manager over the command-line interface. You can find this 32-bit application in the winnt\system32 directory.
File Manager lets you easily handle and modify several file attributes at once. Use the Shift or Ctrl key and the mouse pointer or up and down arrows to select files or directories. (Shift lets you select multiple files that are grouped together; Ctrl works only with the mouse pointer and lets you select multiple files that aren't listed consecutively.) After you select the files to modify, select the File Manager option you want from the toolbar. If the option you want isn't available on the toolbar, you can add it. To customize File Manager, select Options, Customize Toolbar. Then, select the options you want from the available buttons, and click Add. You can add many useful options, such as file compression and decompression.
—Andreas Vollmer
andreas.vollmer@helsingborg.mail.telia.com