Sorting and counting method faster then cat file |

问题:

I have the following script that parses some | delimited field/value pairs. Sample data looks like |Apple=32.23|Banana =1232.12|Grape=12312|Pear=231|Grape=1231|

I am just looking to count how many times A, B or C field names appear in the log file. The field list needs to be dynamic. Log files are 'big' about 500 megs each so it takes a while to sort each file. Is there a faster way to do the count once I do the cut and get a file with one field per line?

 cat /bb/logs/$dir/$file.txt | tr -s "|" "\n" | cut -d "=" -f 1 | sort | uniq -c > /data/logs/$dir/$file.txt.count

I know for a fact that this part runs fast. I can see with certainty it gets bogged down in the sort.

cat /bb/logs/$dir/$file.txt | tr -s "|" "\n" | cut -d "=" -f 1 

After I have run the cut a sample output is below, of course the file is much longer

Apple
Banana
Grape
Pear
Grape

After the sort and count I get

 1 Apple
 1 Banana 
 1 Pear
 2 Grape

The problem is the sort for my actual data takes way too long. I think it would be faster to > the output of the cut to a file but not sure the fastest way to count unique entries in a 'large' text file

回答1:

AWK can do it pretty well without sorting, try this, it should perform better;

cat test.txt | tr -s "|" "\n" | cut -d "=" -f 1 |
   awk '{count[$1]++}END{for(c in count) print c,"found "count[c]" times."}'