Top credits Director Marc Levin. See more at IMDbPro. Photos 2. Add photo. Top cast Edit. Michael Levine Self as Self. Eric Sterling Self as Self. Marc Levin.
More like this. Watch options. Storyline Edit. Untouchable, Brick City exposes how the infiltration of crack cocaine destroyed inner-city neighborhoods across the country. At the center of it all is the rise, fall and redemption of Freeway Rick Ross, a street hustler who became the King of Crack, and journalist Gary Webb, who broke the story of the CIA's complicity in the drug war.
The real Rick Ross is not a rapper. He's an urban legend in South Central LA, a black godfather figure whom most people have never seen, but know by name and reputation. He's 'Freeway' Rick Ross, the man who stood at the center of the crack epidemic, and whose name has been inextricably linked to the CIA-Contra-Cocaine connection.
His story defies all odds and stereotypes and proves that truth is indeed stranger than fiction. Documentary Biography Crime Drama. Rated R for drug content and language including some sexual references. Add content advisory. Did you know Edit. User reviews 5 Review. Top review. A great documentary it was very nice to see how well that put it together in a way you can understand very great gem. Useful links are listed in Section 3: Future Studies, to help us deal with them.
Although a relational database can do almost all the storage work, please remember do not save a blob, like a photo, into a relational database, and choose the right database for the right service. For example, read performance is important for follower service, therefore it makes sense to use a key-value cache.
Users have relationships with other users or objects, so a relational database is our choice by default in an user profile service.
The final step, estimating how many machines are required, is optional, because time is probably up after all the discussions above and three common topics below. It is a little tricky… we need come up with some variables and a function first, and then make some guesses for the values of those variables, and finally calculate the result.
Remember the two bottlenecks we mentioned in section 1. So the final expression would be. There are three common topics that could be applied to almost every system design question.
They are extracted and summarized in this section. The following picture is a brief answer. When the reply message arrives, it unmarshals the results. Generally speaking, RPC is internally used by many tech companies for performance issues, but it is rather hard to debug and not flexible.
Relational database is the default choice for most use cases, by reason of ACID atomicity, consistency, isolation, and durability. One tricky thing is consistency — it means that any transaction will bring database from one valid state to another, different from the consistency in CAP , which will be discussed in Section 2. What if we want to eliminate single point of failure? What if the dataset is too large for one single machine to hold?
Clustering is a decentralized solution. Everything is automatic. Data is distributed, moved, rebalanced automatically. Nodes gossip with each other, though it may cause group isolation.
Sharding is a centralized solution. Data is distributed manually and does not move. Nodes are not aware of each other. In a regular Internet service, the read write ratio is about to Not to mention a distributed join operation across networks. To optimize the read performance, denormalization is introduced by adding redundant data or by grouping data.
These four categories of NoSQL are here to help. The main reason we want to use a key-value cache is to reduce latency for accessing active data. Redis supports data persistence while memcache does not.
The main reason we want to use a document store is for flexibility and performance. Flexibility is obtained by schemaless document, and performance is improved by breaking 3NF. Flexible schema empowers them to move fast. The main reason we want to use a column-oriented store is that it is distributed, highly-available, and optimized for write. It allows us to store entities and the relationships between them.
On the other hand, when we create tables in a relational database for the graph, we model based on the traversal we want; if the traversal changes, the data will have to change. When we design a distributed system, trading off among CAP consistency, availability, and partition tolerance is almost the first thing we want to consider. In a distributed context, the choice is between CP and AP.
Unfortunately, CA is just a joke, because single point of failure is a red flag in the real distributed systems world. To ensure availability, we can add replicas for the data. As to components of the whole system, people usually do cold standby, warm standby, hot standby, and active-active to handle the failover.
Just as everything else, preparation and practice makes perfect. Here are more resources I prepared for you to know more. System Design in Practice. System Design Theories. Four steps to Crack the System Design Interview Breaking down a complex task into small chunks helps us handle the problem at a better pace and in a more actionable way. Clarify Requirements and Specs First things first, the ultimate goals should always be clear.
Pinterest is a highly scalable photo-sharing service: features: user profile, upload photos, news feed, etc. So far so good! To some extent, congrats, we have solved the problem! Discuss individual components and how they interact in detail When we truly understand a system, we should be able to identify what each component is and explain how they interact with one another.
This could lead to more general discussions, such as the three common topics in Section 2, and to more specific domains, like how to design the photo storage data layout … 1. L3 is network layer IP. L4 is transport layer TCP. L7 is application layer HTTP. Stateless There are two major bottlenecks of the whole system — requests per second rps and bandwidth. Service Discovery How do those services find each other? Micro Services For the Pinterest case, these micro services could be user profile, follower, feed, search, spam, etc.
Data and storage is a rather wide topic, and we will discuss it later in Section 2. Back-of-the-envelope Calculation The final step, estimating how many machines are required, is optional, because time is probably up after all the discussions above and three common topics below.
Here is a simple comparison of those protocols.
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