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Large file text editor

UltraEdit's file handling is designed to prevent it from using all the available memory, which would stop other applications from running. What does this mean to you? UltraEdit has no real limit on file size - and can be used to edit large text files.

"...I edit LARGE vital record databases. They can have 6 million lines and be 600 MB in size... Much of the work includes Search and Replace operations to correct bad data as well as consolidate records. Two other editors I tried were either too slow or constantly gave an 'Out of memory indication' They also had trouble editing line endings as one did not support the latest Regular expression commands... UltraEdit has performed what I needed and IT IS FAST..."
Ed M.

There are several configuration settings that can be configured to optimize the editing of large files. Let's take a look at these below...


1. Disable Line Numbers

Disabling line numbers on large files will help make navigation much quicker. You can access this setting by going to Advanced -> Configuration -> Editor Display -> Miscellaneous.

This configuration item is designed for users who are editing large files. It can be very slow to calculate the line numbers when navigating in a very large file. Therefore, UltraEdit provides and option to disable this to improve the performance.

Large File Text editor - UltraEdit


2. Disable temp files

As mentioned above, UltraEdit is a disk based editor, which means it only loads small portions of the file into memory. As UltraEdit uses 64-Bit handling for the file it has no real limit on file size, and does not use excessive RAM for editing. However, when opening the file with a temporary file, UltraEdit must first create a copy of the file in your temporary directory. Copying the file can cause the initial loading to be slower than desired. By editing without temp files, UltraEdit will not first copy the file to your temp directory.

This setting may be accessed in Advanced -> Configuration -> File Handling -> Temporary Files. Enable the option to "Open file without a temp file".

Warning: This does mean you are directly editing the original file so any changes will be permanent.

You may set a threshold for the temp file setting for files above a certain size (specified in KB). The threshold will set a "limit" for using temporary files on files that are over the specified amount. For example, if you set this to 500,000 KB, UltraEdit will not use temporary files when you open a file that is more than 500,000 KB.

Note: for more information on how UltraEdit uses temp files, please see our temporary file power tip.

Large file text editor


3. Disable line terminator conversion

If you've set UltraEdit to automatically convert line terminators to DOS format, you will want to disable this, as this will take a very long time for very large files. You can access this setting in Advanced -> Configuration -> File Handling -> DOS/UNIX/MAC Handling.

This option is designed to allow you to determine if the editor should automatically detect and convert Unix (LF) or Mac legacy (CR) files to DOS (CR/LF) format on open.

large text file editor


4. Disable code folding

Code folding requires parsing of the entire file on open in order for UltraEdit to calculate where a fold should begin and end. As your file grows in size and more and more nested folds exist, the amount of system resources (RAM, CPU) required to display code folding increases as well. For very large files, it is a good idea to disable code folding.

You can disable code folding by going to Advanced -> Configuration -> Editor Display -> Code Folding. Uncheck "Enable Show/Hide Lines and Code Folding" here.


5. Disable the function list

Like code folding, the function list parses an entire file when it is opened in order to locate and display functions. You can disable (hide) the function list by pressing F8 or by going to View -> Views/Lists -> Function List.


6. Disable the XML Manager

The XML Manager is another feature which will parse your entire file on open. You can prevent the XML Manager from automatically parsing files larger than a specified size in Advanced -> Configuration -> XML Manager. Set the "Auto parse XML documents less than" value in MB here.


7. Disable syntax highlighting

To really free up resources for extremely large files, disable syntax highlighting completely (if your large file is syntax highlighted). Disabling syntax highlighting will also automatically disable code folding and function listing as well.

You can completely disable syntax highlighting before opening a large file by going to Advanced -> Configuration -> Editor Display -> Syntax Highlighting and unchecking "Enable syntax coloring".

You can also disable syntax highlighting for the active file only, which in the case of large files is only helpful if done very quickly after open, by selecting "No Highlighting" under "View -> View As (Highlighting File Type)" or, in UE v19.00/UES v13.00 and later, selecting "No Highlighting" in the status bar control (if the basic status bar configuration setting is not enabled).


8. Disable the Line Change Indicator (LCI)

If you plan to make modifications to your large file after you open it, then it is a good idea to disable the LCI for the file. The LCI records saved and unsaved changes per line into memory.

To disable the LCI, go to View -> Disable LCI for All Files.