Checking Bad Blocks in Hard Disk

If you need to see/check how your hard disk in doing, the first thing you look for bad sectors and read/write speed of your hard disk.
Below are a few commands which can be run on your linux machine to check for any errors/speed related or read-write issues

[parag@centos: /home/parag]# fdisk -l

Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xd42ad42a

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          64      512000   83  Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2              64         587     4194304   82  Linux swap / Solaris
Partition 2 does not end on cylinder boundary.
/dev/sda3             587       19458   151582720   83  Linux


[parag@centos: /home/parag]# badblocks -v -s /dev/sda1
Checking blocks 0 to 511999
Checking for bad blocks (read-only test): done
Pass completed, 0 bad blocks found.

[parag@centos: /home/parag]# hdparm -tT /dev/sda

/dev/sda:
 Timing cached reads:   532 MB in  2.00 seconds = 266.05 MB/sec
 Timing buffered disk reads: 248 MB in  3.02 seconds =  82.11 MB/sec
[parag@centos: /home/parag]# hdparm -tT /dev/sda1

/dev/sda1:
 Timing cached reads:   556 MB in  2.00 seconds = 277.54 MB/sec
 Timing buffered disk reads: 236 MB in  3.00 seconds =  78.61 MB/sec

[parag@centos: /home/parag]# hdparm -tT /dev/sda1

/dev/sda1:
 Timing cached reads:   524 MB in  2.01 seconds = 261.21 MB/sec
 Timing buffered disk reads: 174 MB in  3.03 seconds =  57.49 MB/sec

[parag@centos: /home/parag]