i thought the following excerpt from a symantec email would prove at least interesting, and perhaps helpful... some of it pertains to norton users.
Subject: Norton Utilities Technical Support News Bulletin
Date: Mon, 16 Aug 1999
"3.2 Understanding Memory to Improve Performance
Windows sometimes has a problem allocating the correct amount of memory to the disk cache. The disk cache or VCACHE is similar to the swap file. The disk cache swaps between active and inactive RAM while the swap file swaps between RAM and your hard disk (some hard disk controllers have a separate RAM cache on the controller).
The Windows memory manager does not like free memory. Consequently, it will grow the VCACHE such that you will never have more than around 30 MB of unused RAM on your system at any time. VCACHE readily gives the RAM back to applications as they request it, but the lack of free RAM
can be confusing, especially if you are using Norton System Doctor to monitor your RAM use.
3.21 Viewing Memory Usage with Norton System Information
How you calculate memory can also give confusing results. Total or virtual memory is usually your RAM combined with unused disk drive space. The critical distinction is that RAM is extremely fast memory and hard disk storage "memory" (i.e., swap file) is very slow by comparison. Both are
important. You can get a comprehensive overview of your memory usage using the Norton System Information Memory tab.
3.22 Using Norton System Doctor to Monitor Memory Use
[edit: i left this in for continuity...]
Norton System Doctor is an excellent utility for monitoring all kinds of functionality in Windows. There are over 100 different sensors you can select from. Most of the performance sensors can be found in the System Doctor menu under Sensors/Performance/Windows Performance Stats.
Most users don't realize that you can create separate sensor arrays depending on what type of information you want to monitor. For the following examples, we created a memory sensor array using:
- Disk Space
- Memory Load
- Physical Memory
- Cache Memory
- Disk Throughput
- Swap File Size
- Virtual Memory
- Disk Cache Size
To create multiple System Doctor configurations:
1. Save your current configuration through the File menu.
2. Add the sensors you want from the Sensors menu.
3. Choose File and click Save Configuration As.
4. Call the file "Memory".
5. Configure each sensor the way you want by double-clicking the sensor and selecting Properties.
6. Create and save as many configurations as you like for as many purposes as you want.
3.23 Limiting the Size of the RAM Cache to Increase Physical Free Memory
Regardless of how much RAM you have installed on your system, even with hardly anything running, you will find that only about 1/3 is available as free physical memory. A lot of RAM is being used and if you look at the Cache Memory Used sensor you will see where most of it is.
Open and close different applications and watch the sensors to see what is going on. Notice how the cache grows whenever you close an application. You can limit the size of the cache and improve performance by editing your SYSTEM.INI file. Follow these steps to limit your cache file size:
1. Click Start and choose Run.
2. In the Open box, type SYSEDIT and click OK. The System
Configuration Editor opens.
3. Click the SYSTEM.INI title bar. The SYSTEM.INI file moves to the front.
4. Choose the Search menu, and click Find.
5. In the Find field, type VCACHE and click OK. The cursor appears in the [vcache] section of the SYSTEM.INI file.
6. Add the following lines to this section, below the [vcache] label:
MinFileCache=5120
MaxFileCache=8192
NOTE: (1MB =1024 kilobytes)
NOTE: If the [vcache] section does not exist, create it, then add the above lines.
These settings limit the size of the disk cache file to between 5 MB and 8 MB. This should be acceptable for nearly all systems, regardless of the size of the hard drive and the amount of RAM on the system.
7. Choose the File menu, then click Save.
8. Close the System Configuration Editor.
9. Restart the computer so the changes can take effect.
After you complete these steps, you will notice how much more physical memory is free and a decrease in the memory load. As mentioned earlier, Windows will release the memory in the cache as applications request it. Nevertheless, having a very large cache has no benefit. It can cause Windows to swap additional information out to your hard drive swap file and slow down your system.
Windows memory management is a complicated subject about which whole books have been written. We have only scratched the surface here. We hope we have shed some light on this enigmatic subject, and that you find this information beneficial." |
