取り急ぎ新しいgenツールで13GBを作り、読み込んでみました。
※ >>231 の修正ままだしてませんが大丈夫ですかね？

## spec(ハード性能チェック？)
LINUX% ../baka_spec ./aaa_13GB
Mon Jul 23 18:14:22 2018 : starting... 14107393277 bytes read (read block size = 131072 bytes) ./aaa_13GB
〜
Mon Jul 23 18:14:24 2018 : done... 14107393277 bytes read (read block size = 131072 bytes) ./aaa_13GB
read_block_size ::= 131072 bytes, file_size ::= 13453.86 MiB, turnaround_time ::= 2.27 sec, throughput ::= 5920.39 MiB/sec

※複数回実行でだいたい5500〜6000 MiB/sec

## parser
LINUX% ../baka_par ./aaa_13GB
"./aaa_13GB" : size = 14107393277 bytes
Mon Jul 23 18:15:19 2018 : starting... ../baka_par ./aaa_13GB
Mon Jul 23 18:15:19 2018 : section_count = 1, offset = 144275554 bytes, size = 144275513 bytes, turnaround_time = 0.21 sec, throughput =
646.15 MiB/sec
〜
Mon Jul 23 18:15:39 2018 : section_count = 79, offset = 14107393277 bytes, size = 176862384 bytes, turnaround_time = 0.25 sec, throughput = 662.80 MiB/sec
Mon Jul 23 18:15:39 2018 : done... ../baka_par ./aaa_13GB
turnaround time : 20(secs)

ついでに前回のコードでも試しました。↓つづく