CSV file reader

CSV file reader with an e-mail's domain occurrences counter.

Optimization research & ideas

1. Use buffered reading (bufio package),
2. Parallel processing (processes email domains concurrently using worker goroutines),
3. Optimize data structures (structs for readability/maintainability improvement),
4. Benchmark tests (benchmarking different-sized input data files),
5. Code profiling (pprof tool to identify specific bottlenecks).

Environment variables

• To override config variables change the values in .env file. The default values:

  CONCURRENCY=4
  INPUT_CSV_FILE_PATH_DEFAULT=./data/test/customers_3k_lines.csv
  INPUT_CSV_FILE_PATH_0_LINES=../data/test/customers_0_lines.csv
  INPUT_CSV_FILE_PATH_10_LINES=../data/test/customers_10_lines.csv
  INPUT_CSV_FILE_PATH_3K_LINES=../data/test/customers_3k_lines.csv
  INPUT_CSV_FILE_PATH_10M_LINES=../data/test/customers_10m_lines.csv*
  READ_BUFFER_SIZE_IN_BYTES=4096

_{* customers_10m_lines.csv file is stored locally due to the size (over 500 MB). It is used in benchmark tests.}

Screenshots from benchmark execution

• CONCURRENCY=1, READ_BUFFER_SIZE_IN_BYTES=4096

• CONCURRENCY=6, READ_BUFFER_SIZE_IN_BYTES=4096

• CONCURRENCY=12, READ_BUFFER_SIZE_IN_BYTES=4096

• CONCURRENCY=1, READ_BUFFER_SIZE_IN_BYTES=8192

• CONCURRENCY=6, READ_BUFFER_SIZE_IN_BYTES=8192

• CONCURRENCY=12, READ_BUFFER_SIZE_IN_BYTES=8192

• CONCURRENCY=1, READ_BUFFER_SIZE_IN_BYTES=16384

• CONCURRENCY=6, READ_BUFFER_SIZE_IN_BYTES=16384

• CONCURRENCY=12, READ_BUFFER_SIZE_IN_BYTES=16384

Makefile

• Run program

  make run
  

• Run tests

  make test
  

• Run benchmark

  make benchmark