Question

Suppose a disk storage system consists of 5 platters with 10 tracks on each side and 8 sectors in each track. What is the capacity of the system? Assume every sector contains 512 bytes and data can be stored on both surfaces of each platter.

Short answer

The capacity of the disk storage system is 409,600 bytes or 400 KB.

Step-by-step solution

Understanding the Disk Configuration

First, note that each platter in the disk drive has 2 surfaces, and on each surface lies 10 tracks. Thus, each platter has 20 tracks (2 surfaces x 10 tracks per surface).

Calculating Total Tracks

Since there are 5 platters, the total number of tracks is 5 platters x 20 tracks per platter = 100 tracks.

Total Number of Sectors

Each track is divided into 8 sectors. So, the total number of sectors is 100 tracks x 8 sectors per track = 800 sectors.

Capacity of Each Sector

Each sector can store 512 bytes of data.

Calculate Total Storage Capacity

Now, calculate the total storage capacity of the system by multiplying the total number of sectors by the bytes each sector can hold: 800 sectors x 512 bytes per sector = 409,600 bytes.

Conversion to Kilobytes (Optional)

Since 1 kilobyte (KB) = 1024 bytes, the total capacity in kilobytes is 409,600 bytes / 1024 bytes per KB = 400 KB.

Key concepts

Data Storage Capacity

Understanding the data storage capacity of a disk system is crucial because it defines the total amount of data that can be held by the storage device. In our example, we have a disk system made up of multiple platters, tracks, and sectors. Each sector can store a specific number of bytes, which in this case is 512 bytes. To find the total capacity, you multiply the number of sectors by the bytes they can store.

• Calculate the capacity of a single sector: 512 bytes
• Count the total sectors: number of platters, tracks per platter, and sectors per track.
• Multiply the total sectors by sector capacity to get total bytes.

Finally, if desired, convert these bytes into more comprehensible units like kilobytes (KB) or megabytes (MB), by dividing by 1024 bytes per KB. This conversion helps in better understanding and comparison of the storage size.

Disk Configuration

Disk configuration refers to how the components of the disk storage system are arranged and interact with each other, which affects the overall performance and storage capabilities of the system. In this scenario, we have a configuration involving multiple platters, each of which contains multiple tracks distributed on its surfaces.

• Platters: These are flat, disk-shaped objects coated with magnetic material, capable of storing data.
• Surfaces: Each platter has two sides, each used for writing and reading data.
• Tracks: Circular paths on each surface where data is magnetically recorded. These tracks are then subdivided further into sectors.

An efficient disk configuration ensures that data retrieval and storage operations are optimized. For example, in our system, the 5 platters enable the use of both surfaces, effectively doubling the track availability from a single-sided approach.

Sector Size

Sector size is a key factor when understanding how data is stored on a disk. Each sector is a subdivision of a track and represents the smallest storage unit that can be independently written to or read from. In this exercise, each sector holds 512 bytes. The choice of sector size can impact the speed of reading and writing data.

• Smaller sectors might increase the ability to manage smaller files efficiently.
• Larger sectors might speed up large file transfers but can lead to wasted space when storing smaller files.

Understanding sector size is important not only for efficiency but also for optimizing storage space. A well-chosen sector size helps make storage processes faster and often more reliable.

Tracks and Sectors

Tracks and sectors are critical elements in the setup of disk storage. Together, they define how data is organized on a disk, providing structure that allows easy data access and retrieval.

• Tracks: These are concentric circles on the surface of the disk platter where data is magnetically recorded. More tracks mean more data storage potential.
• Sectors: These pie-shaped divisions of tracks allow for smaller segments of data to be accessed independently. Together, sectors on a track create a manageable way to store and access small chunks of data.
• The number of tracks and sectors directly affects the efficiency and capacity of a storage system.

The arrangement of tracks and sectors is calculated carefully to ensure maximum data density while considering the speed and reliability of access. In our example, by having 10 tracks with 8 sectors each on both surfaces of the platters, the system optimizes storage capacity and data access speed.