The real IOPS for exadata

From the graph you can see, the HC and HP IOPS are calculated separately. To illustrate the problem a simple presentation of the form:
Exadata RackDisk TypeDisk CountDisk ModelIOPS
FULL (1/1)HP14 * 12 = 16815000rpm SAS 600G50000
HC7200rpm SAS 3T28000
HALF (1/2)HP7 * 12 = 6815000rpm SAS 600G25000
HC7200rpm SAS 3T14000
QUAR (1/4)HP3 * 12 = 3615000rpm SAS 600G10800
HC7200rpm SAS 3T6000
A simple look can spot patterns: the total IOPS given in the datasheet is actually superimposed.
A quarter rack in ( HC - high capacity ) has only 6000 IOPS

Exadata use hard disk provider and models are as follows, the reader can google the detailed parameters: (Note 2T disk has been discontinued)
600G 1500rpm HP disk: Seagate ST3600057SS, Hitachi HUS156060VLS600
3T 7200rpm HC disk: Seagate ST33000650SS
2T 7200rpm HC disk: Seagate ST32000444SS, Hitachi HUS723020ALS640

Also, exadata's performance is affected by temperature (http://www.dbaleet.org/exadata_how_to_caculate_iops) :
Actually a test disk I / O performance when installed in Exadata steps in Step 9 - INFO: Step 9 RunCalibrate. This step will Exadata Cell disk IOPS and MBPS test. If the hard disk IOPS less than the requirements established in the time of installation will be an error. For example, there is a very common situation: Seagate hard at room temperature below 20 degrees Celsius, IOPS will become poor. See Bug 9,476,044: CALIBRATE IOPS SUBSTANDARD. This problem is a "feature" of the Seagate (Seagate) SAS disk later the Exadata to use the Hitachi (Hitachi) did not find this problem. The Exadata hard disk suppliers on only two, in view of this, in general we do not recommend the computer room air conditioning alignment Exadata blowing heat.

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