We have a 6 SSD, RAID5 volume. The SSD disks we are using are Crucial M4-CT512M4SSD2 firmware 000F. 
We write 100 ~ 200GB data through MySQL InnoDB to the volume daily. The RAID5 volume is only used for MySQL and nothing else.

Output of lsscsi:

```
    [0:0:0:0]    disk    iDRAC    LCDRIVE          0323  /dev/sdb 
    [1:0:0:0]    cd/dvd  iDRAC    Virtual CD       0323  /dev/sr0 
    [1:0:0:1]    disk    iDRAC    Virtual Floppy   0323  /dev/sdc 
    [2:2:0:0]    disk    DELL     PERC H700        2.10  /dev/sda 
    [3:0:0:0]    disk    ATA      M4-CT512M4SSD2   000F  /dev/sdd 
    [3:0:1:0]    disk    ATA      M4-CT512M4SSD2   000F  /dev/sde 
    [3:0:2:0]    disk    ATA      M4-CT512M4SSD2   000F  /dev/sdf 
    [3:0:3:0]    disk    ATA      M4-CT512M4SSD2   000F  /dev/sdg 
    [3:0:4:0]    disk    ATA      M4-CT512M4SSD2   000F  /dev/sdh 
    [3:0:5:0]    disk    ATA      M4-CT512M4SSD2   000F  /dev/sdi 
    [3:0:6:0]    enclosu LSI CORP SAS2X36          0717  -       
    [3:0:7:0]    enclosu LSI CORP SAS2X36          0717  -       

```

Output of smartctl : (see [here](http://www.micron.com/~/media/Documents/Products/Technical%20Note/Solid%20State%20Storage/5611tnfd03.ashx) for attribute 173)

```
for p in d e f g h i ; do smartctl -A /dev/sd${p} | grep 173  ; done

173 Unknown_Attribute       0x0033   098   098   010    Pre-fail  Always       -       67
173 Unknown_Attribute       0x0033   098   098   010    Pre-fail  Always       -       66
173 Unknown_Attribute       0x0033   098   098   010    Pre-fail  Always       -       71
173 Unknown_Attribute       0x0033   098   098   010    Pre-fail  Always       -       66
173 Unknown_Attribute       0x0033   098   098   010    Pre-fail  Always       -       69
173 Unknown_Attribute       0x0033   097   097   010    Pre-fail  Always       -       105

```

And the output for /proc/mdstat:

```
Personalities : [raid6] [raid5] [raid4] 
md0 : active raid5 sdi[6] sdg[3] sdh[4] sdf[2] sdd[0] sde[1]
  2500532160 blocks super 1.2 level 5, 64k chunk, algorithm 2 [6/6] [UUUUUU]
  bitmap: 3/4 pages [12KB], 65536KB chunk

 unused devices: <none>

```

We are unsure why "sdi" is more than 40% more worn out than other disks, as
the parity should be evenly distributed across all disks.