New data from Synergy Research Group shows that Q3 enterprise spending on cloud infrastructure services were almost $33 billion, up 33% from the third quarter of 2019.
Amazon and Microsoft continue to account for over half of the worldwide market, with Amazon market share remaining at its long-standing mark of around 33%, while Microsoft’s share was over 18%. Google, Alibaba and Tencent are all growing more rapidly than the overall market and are gaining market share.
- SaaS 软件即服务，云应用 - PaaS 平台即服务，云数据库 - IaaS 基础架构即服务，云主机
Software architects have borrowed lot of concepts from civil engineering. Multi-tenancy is one such concept.
计算机网络领域上很早就开展服务质量保障方向研究 (Virtual Clock, WFQ, PGPS, WF2Q, SCFQ, Leap Forward, SFQ and Latency-rate scheduling)，主要起步于公平队列
1. Algorithms that allocate throughput or bandwidth in proportion to the specified weights of the clients. Provide proportional allocation of IO resources, such as Stonehenge SFQ(D), Argon, and Aqua. Many of these algorithms are variants of weighted fair queuing mechanisms (Virtual Clock, WFQ, PGPS, WF2Q, SCFQ, Leap Forward, SFQ and Latency-rate scheduling) proposed in the networking literature, adapted to handle various storage-specific concerns such as concurrency, minimizing seek delays and improving throughput. 2. Algorithms that provide support for latency-sensitive applications along with proportional sharing. These algorithms include SMART, BVT, pClock, Avatar and service curve based techniques. 3. Algorithms that support reservation along with proportional allocation. Such as Rialto, ESX memory management and other reservation based CPU scheduling methods.