Category: Design

Design Unique ID Generator in Distributed Systems

In this post I will not be solving a problem, instead I will be talking about something I learned by reading chapter 7 Design a Unique ID Generator in Distributed Systems in the book System Design Interview by Alex Wu.

The idea of a unique ID is a requirement in most distributed systems. In my case, some years ago I was developing a storage server and needed to name the objects of different types and sizes a client might wish to store and of course, at some later point in time, retrieve. The idea of a file system path did not make sense because it would be nearly impossible to keep the same immutable configuration among many distributed systems with a huge capacity. Continue reading “Design Unique ID Generator in Distributed Systems”

Producer and Consumer – Part 4

We are quickly approaching the end of another work week. In the Twin Cities of Minneapolis and St. Paul it appears that most businesses are back to normal. The only exception is that many office workers are still working from home and people is required to wear a mask when in public spaces. Most people that want to be vaccinated against COVID-19 have done so. We need to get most (never generalize) people to comply in order to achieve herd immunity.

This is the fourth installment of the sequence of posts related to a producer and consumer connected via TCP/IP. In this post we will not add functionality to the producer or consumer. We will explore some functions and methods that we have at our disposal when encrypting and decrypting files using the Advanced Encryption Standard. Continue reading “Producer and Consumer – Part 4”

Producer and Consumer – Part 3

It is Friday once again. The cleaning crew is at home. I have been listening to the vacuum for a few hours. They should be done shortly.

I have to get a COVID-19 test this afternoon. On Monday I will be having a procedure and the clinic requires a COVID test in the past 72 hours no matter if you have already received the complete doze of a vaccine. I was going to get this procedure done a couple years ago, but with some travelling plans and then COVID did not have an opportunity to get it done.

Today I suggested to my wife if we could have Asian from Trader Joe’s for lunch. She suggested noodles with an Italian sauce we fixed last week. We were able to fill five one-pint containers and put them in the outside freezer. The sauce turned out very good. We made it last Saturday when my wife’s brother and wife had lunch with us. We used a few pounds of chuck and Italian pureed tomatoes. Hopefully the cleaning crew will leave soon so we can have an early lunch. Continue reading “Producer and Consumer – Part 3”

Producer and Consumer – Part 2

Yesterday the temperature in the Twin Cities of Minneapolis and St. Paul reached 72F which is quite pleasant for this time of the year. Today we are expecting 42F for a high. That is a drop of 30F! At least the day is forecasted to be sunny.

I also received a message from Gleves48061@hotmail.com regarding my post Revenue Milestones in Java. Not sure what it was all about so I will not comment on it at this time. If I could get an updated comment, I will review and reply as needed. Thanks. Continue reading “Producer and Consumer – Part 2”

Producer and Consumer

Hope you are doing well. I fully understand that not all countries are moving quickly to vaccinate most their population against COVID-19. Hopefully the efforts have already started and will be completed soon. Here in the USA it seems that every state is moving at its own pace. That said, a large amount of people have received at least the first of two jabs. The youngest I know of is of age 21. The world needs to get as much of its population vaccinated as possible to achieve herd immunity. If this is not done the virus will continue to mutate and the threat of COVID-19 might remain for years or decades.

It seems that Israel is leading the vaccination process. As in many other countries, there are some people that do not wish to get vaccinated. The prime minister of Israel has made some clever, and for what I understand legal changes to motivate all their citizens and residents to get a COVID-19 vaccine.

In a nutshell the idea is that the good of the majority needs to prevail. People will not be forced to get a vaccine unless there are medical reasons. Besides that, the population needs to show a vaccine passport to work where there is human contact with others. If the person wishes to attend events and places where they could possibly transmit COVID-19, they need to have a COVID test in the previous 48 hours. The COVID tests used to be free but in the near future people will need to pay for a test. So if a person for without a real medical issue does to get the vaccine but wishes to mix and mingle with others, they will have to pay and get a COVID test every other day. I guess Israel will be one of the countries that will reach heard immunity in the very near future. In my humble opinion, we in the USA need to start thinking about each other and work for a common goal. Continue reading “Producer and Consumer”

Design a System like Yelp

Last week I was talking with a software manager about the design of a feature for Yelp. For starters I am not a Yelp user. If you are like me, you can find more about Yelp in this Wikipedia link.

It seems that Yelp is a business directory and uses a crowd-source review forum to collect information and ratings about different businesses (i.e., barber shops, cinemas, coffee shops, restaurants). It happens that I use OpenTable for restaurant-reservations. Apparently on both platforms one can get nearby restaurants of desired types in a specified distance so you can decide where to go for dinner (or for that matter for any meal at any time) tonight. A side fact, both companies happen to be headquartered in the San Francisco, California area. Continue reading “Design a System like Yelp”