Evolution of large-scale Web site architecture (i)

There is a lot of sharing on the internet about the architecture of the website, some of which are mainly analyzed from the perspective of transport and infrastructure (heap machines, do clusters), too concerned about the implementation of technical details, ordinary developers do not understand the basic.

This article will mainly introduce the expansion of the large-scale Web site infrastructure, the next part of the focus from the application perspective to introduce the expansion and evolution of the site architecture.

Grassroots time, rapid development of the site and online. Of course, it is usually just the first test of water, the size of the user is not formed, the economic capacity and investment is very limited.

Have a certain amount of business and user size, want to improve the speed of the site, so, the cache appeared.

Market response is also good, the number of users growing every day, the database crazy read and write, and gradually found a server is not going to hold up. So, decided to separate the DB and the app.

A single database is also feeling fast, generally will try to do "read and write separation." Because most of the Internet "read more write less" the characteristics of the decision. The number of salve depends on the read/write ratio evaluated by the business.

The database level is mitigated, but the application level is also a bottleneck, due to the increase in traffic, coupled with the early programmer level of limited write code is also very bad, people mobility is very difficult to maintain and optimize. So the most common way is to "heap machines."

Add the machine who will add, the key is to add after the effect, after the addition may cause some problems. For example very common: page output caching and local cache issues, session save issues ...

Here, the DB level and the application level have been basically scaled up, and you can start to focus on other aspects, such as the accuracy of the site search, the reliance on the DB, and the introduction of full-text indexing.

The Java domain uses the more is Lucene, SOLR, and so on, while PHP domain uses more is sphinx/coreseek.

So far, a medium-sized website architecture capable of hosting daily millions visits has basically been introduced. Of course, every step of the extension there will be a lot of technical implementation of the details, the subsequent time will write the article alone to analyze those details.

Let's continue with the next chapter.

Evolution of large-scale Web site architecture (i)