The difference between Alibaba Cloud ECS shared and universal (exclusive) instances where? How to choose? Open the official home page of Alibaba Cloud and you will see many different types of ECS, the most common and cheapest shared xn4 instance and universal (exclusive) instance. The Weieis blog mainly talks about the differences between these two instances and how to choose them.
An instance is what we usually call VPS. An instance can be regarded as a VPS host. In order to distinguish individual users from enterprise users, Alibaba Cloud has introduced shared instances and universal (exclusive) instances. Among them, the generic instance was called exclusive instance when it was first launched in 2016, and later changed its name. We don't care about Alibaba Cloud's marketing strategy, but only about the performance and price related to our individual users. Before purchase Click me to get it Alibaba Cloud 1000 yuan voucher gift package, including Alibaba Cloud 100+products, can save money by deducting from 50 yuan.
1. The difference between shared instances and universal (exclusive) instances
Shared instances share more resource performance in resource utilization, so it cannot guarantee the stability of instance computing performance, but the cost is relatively lower. For example, the shared basic instance xn4 is like this. In normal use, one xn4 will share idle CPU resources and idle system resources with other xn4. That is, if your shared instance occupies too much system resources during use, the system resources occupied by other shared instances will be reduced accordingly, and vice versa.
Each CPU of the universal (exclusive) instance is bound to a physical CPU hyper thread. There is no CPU resource contention between instances. The instance computing performance is stable and has strict SLA guarantees. Universal instances are defined as enterprise configurations precisely because they can always provide stable performance.
It can be seen from the figure above that the resource request of shared instance A is allocated to two HTs (hyper threads) of different cores, and there is resource contention with the HT of instance B, which results in unstable instance performance; Then look at the resource requests of the universal (exclusive) instance A and instance B on the right, which are allocated to two HTs of the same core. A and B will not compete directly, so that the performance of each instance is stable, and there will be no ups and downs.
Maybe a friend still can't understand so many professional terms. Lao Wei explained in plain English that a shared instance is equal to one person (Ht hyper thread) serving two customers (instance A and instance B). If you are too busy, it is inevitable that the service is not in place (unstable); The universal type is that one person (Ht hyper thread) only serves one client (instance), ensuring the quality of service standard, and the quality of service is very stable.
After reading Lao Wei's explanation, some netizens said that since shared instances are unstable, why not use universal (exclusive) instances? This is about cost performance. According to the cost performance ratio, shared instances are more practical. At first, one core, one gigabyte of memory, 40 gigabytes of efficient cloud disks are configured at 394 yuan/year; The general (exclusive) instance is initially configured with a 2-core 8G memory efficient cloud disk of 242 yuan/month. The gap between the two is too big. Before purchase Click me to get it Alibaba Cloud 1000 yuan voucher gift package, including Alibaba Cloud 100+products, can save money by deducting from 50 yuan.
2. How to select shared instances and universal (exclusive) instances
Since the above mentioned universal (exclusive) instances are too high in initial configuration, expensive in price, and designed for enterprise level services, we certainly choose shared instances. It can be said that many websites you see on the network (using Alibaba Cloud servers) use shared instances. They are indeed shared system resources, and the speed of opening pages is also very fast during normal access, There was no jam. Therefore, we should believe in the stability of Alibaba Cloud servers, which is the basis for Alibaba Cloud to occupy half of the domestic cloud service market. Before purchase Click me to get it Alibaba Cloud 1000 yuan voucher gift package, including Alibaba Cloud 100+products, can save money by deducting from 50 yuan.
There is a lot said above. It may not be easy to understand for new friends. What is the difference between Alibaba Cloud ECS shared and universal (exclusive) instances? How to choose? For our personal websites, blogs, and projects, the sharing instance is the most cost-effective at the beginning. When the traffic reaches a certain amount in the later period, consider whether to upgrade to the universal (exclusive) instance.
