HOWTO Improve Large File Copy with NT

Sometimes you copy files over the network and you wonder, why it takes ages for just a few MB. This problem may be a symptom of a problem with the way that the Server service interacts with the system cache in certain configurations.

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You may be able to work around this problem by tuning the server to prevent the providing of large amount of memory to the system cache. You even don't need to work in the registry, for a change.

    To do this, perform the following steps:
  1. Start Control Panel Network.
  2. From the Installed Network Software box, select Server, and then click Configure.
  3. If the option "Maximize Throughput for File Sharing" is currently selected, you may get better performance during large file copy operations by selecting the "Maximize Throughput for Network Applications" or "Balance" options.
  4. If you elected to make a change in Step 3, restart your computer so the change can take effect.

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MORE INFORMATION

The "Maximize Throughput for File Sharing" option permits the system cache to use more available memory than it would otherwise. In this situation, the available memory can drop to levels that result in heavy swapping activity on the hard disks in order to accommodate requests from user or system applications that may subsequently need to be swapped into memory.
The cache manager periodically gives up memory that it has allocated so that the system will never run completely out of memory due to caching alone. This can happen whenever a file copy operation is complete or when a threshold value is reached. This means that the problem described above does not occur if a series of smaller files are copied. The threshold value, when "Maximize Throughput for File Sharing" option is not selected, is enough higher than the threshold value when the problem does not occur there either.
This problem is also more noticeable on computers with lower total physical memory. When more total physical memory is available, the minimum available memory threshold is also higher, which can alleviate the problem.