Question

You are working on an iPhone application which displays a table of data which can be sorted, filtered, and paged. This table has 800000 records in it, and each record is exactly 150 bytes. You decide that you want customers to be able to perform all sorting, filtering, and paging on the client-side so that customers can still interact with the table even if they lose their Internet connection.

In Q1-Q2 2019, the average mobile download speed was 33.88 megabits per second. Assuming that all sorting, paging, and filtering is performed on the client side, and ignoring the effects of compression, etc., how long will it take (in seconds) for the customers to view the first page's worth of data? Remember that 1 kilobyte is 1024 bytes and that 1 megabyte is 1024 kilobytes.

Your Answer:

Answer 1

Since all processing is done on the client's side, so the table will first be downloaded completely, and then the rendering would start from first page onwards.

Thus, time required (in seconds) to download the file

= (Size of file in bits) / (Download speed in bits per second)

Now, total size of file in bits

= (Number of records) * (Size of each record in bytes) * 8

= (800000) * (150) * 8

= 960000000 bits

= 9.6 * 10⁸ bits

Download speed

= 33.88 megabits per second

= (33.88 * 1024) kilobits per second

= (33.88 * 1024 * 1024) bits per second

= 35525754.88 bits per second

= 3.552575488 * 10⁷ bits per second

Thus, time required in seconds

= (9.6 * 10⁸) / (3.552575488 * 10⁷)

= 27.023 seconds