why two values in the log: data buffer = 79691776/99614720

[Daniel,Wu]

They have 2 values in the log, do they mean max and min?

2011-08-13 18:18:16,661 INFO org.apache.hadoop.mapred.MapTask: data buffer = 
79691776/99614720
2011-08-13 18:18:16,661 INFO org.apache.hadoop.mapred.MapTask: record buffer = 
262144/327680