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1:  real 24.33 user 0.04 sys 19.49
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0:  262144+0 records in 262144+0 records out real 5.73 user 0.08 sys 5.64
1:  262144+0 records in 262144+0 records out real 5.62 user 0.08 sys 5.53
2:  262144+0 records in 262144+0 records out real 5.73 user 0.08 sys 5.64
3:  262144+0 records in 262144+0 records out real 5.78 user 0.08 sys 5.68