Perform bechmarks on the filesystem

To test the speed of the filesystem (not the physical disk!) you can
use the following script: 
 
 
 #!/bin/bash 
 
 # USAGE: 
 # ./speed_test.sh /path/to/my/file /path/to/destination number_of_tests 
 
 NUM_TESTs = $3 
 SUM = 0 
 for i in $( seq 1 $NUM_TESTs ) ; do 
 
 REC = ` dd if= $1 of= $2 2 > some_random_file_ ; cat some_random_file_ | cut -d " " -f8 | tail -1 ` 
 
 SUM = ` echo $SUM + $REC | bc ` 
 
 done 
 
 RESULT = ` echo $SUM / $NUM_TESTs | bc | awk '{ str1=str1 $0 }END{ print str1 }' ` 
 
 echo $RESULT MB/s 
 
 #clean up 
 rm some_random_file_ 
 rm $2 
 
 To make a big file, use 
 
 cat /dev/zero > zerofile 
 and abort it with CTRL-C after a few seconds. 
 Alternatively, you can use something like 
 dd if=/dev/zero of=file.out bs=1MB count=500 
 to create a 500MB file. 
 
 Start the script like this: 
 
 ./speed_test.sh /mnt/sda1/zerofile /mnt/sdb1/zerofilecopy 3 
 The result will be something like 
 ./speed_test.sh ./zerofile ./2delete 5 
 237 MB/s