c++ - C# I/O vs C I/O -

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i have c# program needs read tens hundreds of millions of records flat text file. there significant performance gain using p/invoke call unmanaged c/c++ dll handles of file input on separate thread, or insignificant gain in performance, such better handle file io in c#?

there not significant performance gain in using c/c++ dll. c# runs in environment quite efficient jit compiler, guess code performance limited hard disk read speed of approximately 100 mb/s. of course, if have ssd, mileage may vary.

do note if 1 record e.g. 1000 bytes , reading 100 million records, means 100 gigabytes. reading takes 1000 seconds, i.e. more 15 minutes, due slow speed of hard disk drive.


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