Journal Entry Week 2

 One of the most interesting things I learned this week was about CPU scheduling. Everyday I use my phones or laptop, I take for granted the amount of processing power that is being the machine! This week the most tedious thing we did was hand calculate turn around time and response time. We also had to assume that there was only one available core, as other resources were not factored into the calculation.  Among the different kinds of scheduling , each of them have their own strengths and weaknesses. For example the Round- Robin scheduling excels at response time but sacrifices turnaround time in the process. By frequently switching to different jobs in small slices, the computer is able to work on all jobs what seems like simultaneously. With responses times at basically zero,  the amount of context switching that the computer has to do may drastically increase the turn around time.  Another scheduling algorithm we applied this week was the shortest Job priority. With this schedule, the computer while constantly prioritize the shortest possible job thus decreasing the turnaround time.  The most relatable example of this in the real world is a line building up at the cash register in a grocery store. Assuming the there is a person ahead of us and plans to buy a large quantify of items, (and all we have is a measly candy bar), the first in first out (what the grocery store line represents) is lower in effect compared to the shortest job first. 

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