50 time is optimal on average. For the getline () we're currently talking about it me run into more than 100 times!. Here is a rudimentory comparison table from a while ago, comparing the different versions and access methods of the two CSV modules (click on download to see it as a table):

Short version (higher is better):
                   Text::CSV_XS         Text::CSV_PP
             ----------------------  ----------------
             0.23  0.25  0.43  0.65  1.00  1.06  1.19 
             ====  ====  ====  ====  ====  ====  ==== 
combine   1    70    67    98    96    15    15    14 
combine  10    48    47    96   100     6     6     5 
combine 100    40    40    96    99     5     5     4 
parse     1   100    86    88    89    12     6     5 
parse    10   100    98    93    91     8     3     3 
parse   100    97   100    95    97     7     2     2 
print    io    87    86    94    99    79     6     5 
getline  io    64    64    93   100     -     2     1 
             ----  ----  ----  ----  ----  ----  ---- 
average        75    73    94    96    16     5     4

[download]

Long version: 

CSV_XS      0.23 0.25 0.26 0.27 0.28 0.29 0.30 0.31 0.32 0.34 0.35 0.3
+6 0.37 0.40 0.41 0.42 0.43 0.44 0.45 0.46 0.50 0.51 0.52 0.53 0.54 0.
+55 0.56 0.57 0.58 0.59 0.60 0.61 0.62 0.63 0.64 0.65
            ==== ==== ==== ==== ==== ==== ==== ==== ==== ==== ==== ===
+= ==== ==== ==== ==== ==== ==== ==== ==== ==== ==== ==== ==== ==== ==
+== ==== ==== ==== ==== ==== ==== ==== ==== ==== ====
combine   1   70   67   66   67   63   96   96   98   95  100   93   9
+6   97   97   99   95   98   97   97   97   95   94   94   94   96   
+96   96   94   95   91   96   98   98   96   98   96
combine  10   48   47   47   47   47   98   96   97   98   97   94   9
+3   96   94   96   96   96   98   96   96   97   93   94   93   98   
+99   99   99   99   97   98   99   99   99   99  100
combine 100   40   40   39   40   40   96   94   95   95   95   95   9
+4   95   94   95   95   96   96   96   95   95   93   93   93   98   
+99   99  100   99   97  100   98   99   99   99   99
parse     1  100   86   86   84   77   89   91   91   90   87   87   8
+9   90   89   89   89   88   89   83   89   88   87   87   87   88   
+89   88   88   86   87   88   88   87   86   87   89
parse    10  100   98   96   96   93   94   97   96   97   95   97   9
+6   97   92   95   94   93   94   84   92   93   89   89   93   92   
+95   95   95   90   91   91   91   90   91   96   91
parse   100   97  100  100  100   97  100  100   97   97   97  100  10
+0  100   95   95   97   95   95   85   95   95   95   95   97   97   
+97   95   97   95   97   97   97   95   97  100   97
print    io   87   86   87   86   86   95   96   96   96   96   90   9
+3   94   95   94   95   94   94   95   94   95   91   92   93   96   
+97   97   97   96   97   99   97  100   99   98   99
getline  io   64   64   63   63   61   64   64   62   63   62   64   6
+3   65   96   99   98   93   93   95   93   93   93   93   95   96   
+98   96   95   95   99   97   96   98  100   95  100
            ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---
+- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- --
+-- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
average       75   73   73   72   70   91   91   91   91   91   90   9
+0   91   94   95   94   94   94   91   93   93   91   92   93   95   
+96   95   95   94   94   95   95   95   95   96   96

CSV_PP      1.00 1.02 1.05 1.06 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.1
+5 1.16 1.17 1.18 1.19
            ==== ==== ==== ==== ==== ==== ==== ==== ==== ==== ==== ===
+= ==== ==== ==== ====
combine   1   15   15   15   15   16   15   16   15   15   16   14   1
+4   14   14   14   14
combine  10    6    6    6    6    6    6    6    5    6    6    5    
+5    5    5    5    5
combine 100    5    4    5    5    5    5    5    4    4    4    4    
+4    4    4    4    4
parse     1   12   12   11    6    6    6    6    6    6    6    5    
+5    6    5    6    5
parse    10    8    8    7    3    3    3    3    3    3    3    3    
+3    3    3    3    3
parse   100    7    7    7    2    2    2    2    2    2    2    2    
+2    2    2    2    2
print    io   79   76    6    6    6    6    6    6    6    6    5    
+5    5    5    5    5
getline  io    -    -    4    2    2    2    2    1    1    1    1    
+1    1    1    1    1
            ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---
+- ---- ---- ---- ----
average       16   16    7    5    5    5    5    5    5    5    4    
+4    5    4    5    4

[download]

Enjoy, Have FUN! H.Merijn

In reply to Re: Efficiency issue when reading large CSV files by Tux
in thread Efficiency issue when reading large CSV files by Takuan Soho

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