Here is time parsing csv with regexCSV and standard CSV:

time ruby regexCSV.rb
26908

real    0m10.072s
user    0m9.414s
sys     0m0.660s


[root@taamportable GMS]# time ruby standardCSV.rb
26907

real    1m48.296s
user    1m36.853s
sys     0m11.188s


Significantly higher than python csv (which is written in c)

[root@taamportable GMS]# time python x.py
26907 
 

real    0m0.311s 
 user    0m0.302s 
 sys     0m0.009s