Question

For a mass storage device e.g. a hard disk or solid state disk give an example of data processing when:

• sustained rate was used
• burst rate was "triggered"

Answer 1

For the first question I would like to give one simple example of a supercar:

sustained rate was used:

• A supercar can have insane top speed but one can't maintain it for a long time because of the overhead on the engine, One can also understand this by Usain Bolt's example.
• His speed can be only helpful in 100m race, in the marathon, he might not able to manage his top speed at all times.
• The same is applicable to HDD/SDD, in all most all scenario sustained rate is used, you can check HDD/SDD read/write usage in the Task Manager performance tab (if using windows), even if HDD is utilizing 100% Disk usage at a given time(like if you are using too many Chrome Tabs), it is unlikely to hold this rate because it deteriorates the quality of storage device due to more overhead. 1
• So in general while doing simple work like watching any videos or working on any document, most probably sustained rate is used.

burst rate was "triggered":

• Burst Rate is used when there is a huge amount of important data, which can not be stored on temporary storage devices like RAM, the burst rate is triggered to transfer this data to persistent storage burst buffer space.
• This data is transferred too quickly to Burst buffer and but Burst buffer is not the data's destination.
• After receiving this data from temporary storage it transfers this data to Persistent storage like HDD at normal speed.
• The problem with Temporary storage is it can be erased due to any abnormality so it is required to transfer this important data to permanent storage as soon as possible, this is when the Burst rate is triggered, allocating continuous storage big chunks of data is transferred parallelly.
• For example, when a system interrupts occurs and the processor is doing critical computation, at this time interrupt is a priority but data is also needed to be stored somewhere for further processing, at times like this burst rate is triggered.

Thank you.