Mpp File Size Is Huge' title='Mpp File Size Is Huge' />Sorting Huge Text Files Code. Project. Introduction. One interviewer asked me how I would sort lines in a 5. GB text file, if I had only 1. GB of RAM. The task seemed to me quite interesting and I couldnt resist from implementing it the next morning. Background. I wish I had some background on it, but I really dont know much about external sorting algorithms. I wrote this code mostly using intuition, so I would appreciate if you share your knowledge on more advanced techniques in comments. Algorithm. In order to sort the file, I first split it to smaller files. On the first iteration, I run through the input file and find all lines that start from the same character. If some resultant files are still larger than the amount of available memory, I split them by first two characters and so on. Then each smaller file is being sorted in memory and saved on the disk. The final stage is merging the sorted list of sorted files into a single file. Example. Consider the following text file apricot. For simplicity lets assume that we run a very ancient computer and cant afford sorting files more than 1. Our input file is larger, so we need to split it. We start the process by splitting by one character. So after the first step, we will have three files stronga. Files m and o can now be sorted in memory. However file a is still too large. So we need to split further. ScreenshotPasteSpecialPicture.png' alt='Mpp File Size Is Huge Casino' title='Mpp File Size Is Huge Casino' />Grab PayPal logos, icons, images and acceptance marks for your website at PayPals online logo center. MS Project 2010 File Size is growing exponentially. Still rather large though but was surprised that colour to text would add such an increase the file size. Author. Huge mpp with lot of unused hidden data. How to reduce. b291d8da631fhugemppwithlotofunusedhiddendatahowto. File av is less than ten bytes, however file ap is still large. So we split once again. Now that we have five small sorted files instead of a single big one, we range them in order of their beginnings and merge them together, saving results into output file. Looks good, however this algorithm has a flaw consider that the input file contains five gigabytes of the same line repeated many times. Its easy to see that in this case the algorithm will be stuck in an endless loop trying to split this file over and over again. A similar problem is illustrated below. Any Video Converter Keygen 2011. Consider we have the following strings and our memory is not sufficient to sort them. Mpp File Size Is Huge LabiasAs they all start from a, they all will be copied into the same chunk in the first iteration. In the second iteration, we are going to split line by first two characters, however line a consists of only one character Well face the same situation in each iteration. I handle these two problems by separating strings smaller than current substring length into a special unsorted file. As we dont need to sort it, the file can be of any size. If only case sensitive sorting were supported, it wouldnt be necessary to save short lines into a file, but only calculate their number. Incidentally the algorithm is stable, i. Using the Code. The class Huge. File. Sort contains the following properties, which specify how sorting will be performed Max. File. Size the maximum file size that can be sorted in memory 1. MB by defaultString. Comparer comparer used for sorting case sensitive Current. Culture by defaultEncoding the input file encoding UTF8 by defaultThe main method is called simply Sort. It accepts two strings input and output file names. If size of input file is less than Max. File. Size, its content is simply loaded into memory and being sorted. Otherwise the procedure described above is being performed. Sortstring input. File. Name, string output. File. Name. chunks new Sorted. Dictionarylt string, Chunk. Info Comparer. File. Infoinput. File. Name. Length lt max. File. Size. Sort. Fileinput. File. Name, output. File. Name. var dir new Directory. Infotmp. if dir. Exists. Deletetrue. Create. Split. Fileinput. File. Name, 1. Mergeoutput. File. Name. During the execution, temporary directory tmp is created in the current folder. For the sake of better display, final set of temporary files is not deleted and stays in the folder. In production code, please uncomment two lines in the Merge method. Mergestring output. File. Name. using var output File. Createoutput. File. Name. foreach var name in chunks. Value. Close. if name. Value. No. Sort. File. Name null. Copy. Filename. Value. No. Sort. File. Name, output. Value. File. Name null. Copy. Filename. Value. File. Name, output. The core of the algorithm is the splitting method. Split. Filestring input. File. Name, int chars. Dictionarylt string, File. Chunk Comparer. Stream. Readerinput. File. Name, Encoding. Peek 0. Read. Line. if entry. Length lt chars. Chunk. Info name. Info. if chunks. Try. Get. Valueentry, out name. Info. chunks. Addentry, name. Info new Chunk. Info. Info. Add. Small. Stringentry, Encoding. Substring0, chars. Html Dj Website Template'>Html Dj Website Template. File. Chunk sfi. if Try. Get. Valuestart, out sfi. File. ChunkEncoding. Addstart, sfi. Appendentry, Encoding. Value. Close. if file. Value. Size max. File. Size. Split. Filefile. Value. File. Name, chars 1. File. Deletefile. Value. File. Name. Sort. Filefile. Value. File. Name, file. Value. File. Name. Chunk. Info name. Info. if chunks. Try. Get. Valuefile. Key, out name. Info. Addfile. Key, name. Info new Chunk. Info. Info. File. Name file. Value. File. Name. File. Chunk and Chunk. Daz Gen 3. Info are auxiliary nested classes. The former is the helper that corresponds to new files on each iteration and is used to write lines into files. The latter contains information about the data that will be merged into the resultant file. During the recursive work of the algorithm, the program populates the sorted dictionary that maps text line startings to the instances of Chunk. Info. Sorted. Dictionarylt string, Chunk. Info chunks Chunk. Info contains the following information File. Name the name of the file that contains sorted lines starting with the given substring. No. Sort. File. Name the name of the file that contains non sorted lines equal to the given substring may differ by caseBoth properties can be null. The class also contains method Add. Small. String that writes a given string into file No. Sort. File. Name. Test application requires three command line arguments input file name, output file name and max file size in bytes. It performs case insensitive sorting of UTF8 files. Limitations. If you want to break it, pass in a large file with little or no line ends. As the algorithm uses standard Text. Reader to read text line by line from the file, it is not designed to handle such input data. History. 20th November, 2.