file handling - reading big data in C++ -


im using c++ read large files on 30000 lines , 3000 colums. (30000 x 3000) matrix. im using 2d vector push read data. need process couple of times. there way optimize reading process?

i give ideas not exact solution. because not know full details of system.

  1. actually if have big file data , data change in next reading. try use data base methodology.
  2. for performance can use concurrent file reading (read same file part part using multiple thread).
  3. if need process data well, use separate thread(s) process , may possible link queue or parallel queues.
  4. if data length fixed (such fix length numbers). , if know changed location, try read changed data instead of reading , processing whole file again , again.
  5. if of above not helped use memory mapping methodology. if looking portability, boost memory-mapped files support reduce works

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