UltraEdit allows you to edit files greater than 4GB (up to a size of 2^64-1), which can affect performance. You can edit these very large files without using temporary files, which speeds up the process of saving by removing the time necessary to copy to a temporary file.
WARNING - If you set your installation to open files without using a temp file, all changes are permanent!
When this setting is enabled, a warning appears each time a file is opened. You can manage this feature in the Configuration dialog box, accessible by going to Advanced > Settings. Navigate to File Handling > Large Files, and then select one of the following options:
Numerous options are available for you to manage actions once a large file triggers your set threshold. The "Large file threshold (KB)" field lets you a value the designate files that are equal to or larger than this value be loaded without creating a temporary file. Files smaller than the set threshold load normally, creating a temporary file. Setting this value to zero means that all files load without creating a temporary file. Note that the threshold field is applicable only if the option to open files without the temporary file is set.
One threshold option to note is that "Disable line numbers" improves the performance when navigating around large files as less disk accesses are required to track the line numbers.
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