What is virtualization:
“By virtualization, we mean the creation of a virtual version of a resource normally provided physically. Any hardware or software resource can be virtualized: operating systems, servers, memory, disk space, subsystems. ” with these words Wikipedia defines Virtualization.
We can say that today by virtualization we mean, commonly, the technical one that allows a physical host, PC or server, to host multiple virtual machines, sharing the resources of the single host through different environments.
A bit of history – Some myths to dispel:
We often hear about, or read about virtualization as if it were the most advanced stage of information technology, in reality it is not so in fact virtualization is a technology developed in the 1960s to partition the hardware of large mainframes.
Current computers based on the x86 architecture reproduce the same rigidity and under utilization problems that characterized mainframes in the 1960s. In the 1990s, virtual machines with x86 architecture were finally started.
Why virtualize:
In the last twenty years, the proliferation of applications and the ever lower cost of hardware has led to an exponential growth in the number of machines in the data centers, hence a consequent exponential increase in management costs and spaces to be set up, imagine that the data centers Google hosts over 500,000 servers. This exponential growth that has characterized the last few years has determined:
- The very low use of individual machines, accurate estimates affirm that the average use of a server is around 10% of its capacity.
A sharp increase in the cost of the overall infrastructure
A high increase in the cost of managing the infrastructure (Energy, connectivity, equipped rooms, staff)
Virtualization today:
The virtualization market, today, offers many open and proprietary solutions, discussing the technological features of these solutions is beyond the scope of this article; therefore the following are the links of the most popular products, Open and not, used both as regards home virtualization and for enterprise virtualization:
Vmware, Microsoft Hyper-V, Xen, Virtualbox, Virtuozzo, etc are examples.
It is necessary and necessary to spend a few words for VMWARE, which has invented a new market, that of Virtual Appliances, or a repository where everyone can freely or even pay, make available their virtual machines, already installed and increasingly often preconfigured, thus facilitating the lives of many IT employees and enthusiasts, making the download and use paradigm possible even for very large applications, such as ERP, CMS, SCM etc.
If you imagine the advantages both in terms of speed and in terms of the possibility of having dozens of machines ready for use, you realize that this premise opens scenarios that until recently were unimaginable.
The virtual market created by VMWARE.
Database and virtualization:
It is therefore interesting to discover the role of DBs in a virtualized way. It is not difficult to understand how data and know-how represent the true heritage of modern organizations, small or large.
What are large and powerful infrastructures for, without data and without the people who use them? … This post-Fordist reflection of our time already offers many food for thought on the importance of the flexibility that virtualization allows.
In our society, databases play a fundamental role. Many of our daily actions result in read / write / modify or delete data on databases, for example when we answer the phone, somewhere there will be a register at the telephone company datacenter which will store the general information of our call ( calling number, date and time, called number, duration etc), another example when we use electricity (in any way) our electricity meter will calculate the energy consumption and subsequently this value will be read and stored somewhere in a database, and from there, our bill will be calculated.
It is therefore easy to guess that the databases have proliferated exponentially and therefore, like all applications, and for the reasons explained above they are subject to virtualization.
The purpose of this article is to propose some preconfigured and ready-to-use virtual solutions, freely downloadable from the VMWARE virtual market. Solutions are proposed that include MySQL both as part of complete platforms (for example LAMP platforms, WordPress installations, Linux + Apache + MySQL + Rails platforms) and as only DB servers, in order to offer all users, enthusiasts, beginners and the experts of the ideas to take advantage of using MySQL through a pre-configured system of virtualization.
One more virtual software available in the global market is freeware. It is called Oracle VM. Here you can find out more detail about What is Oracle VM. Keep connected with our Expert DBA Team Club blog for getting more and the latest database news including Oracle DBA Tutorials, tips and guidance. You can see some of the articles from blog page of Dbametrix too.
When you want to make a strong Oracle DBA career then you should be aware of database services and other database technology. Without having knowledge of Oracle internals, Oracle performance tuning, and skill of Oracle database troubleshooting you can’t be an Oracle DBA expert.
This expert DBA Team club blog always provides you latest technology news and database news to keep yourself up to date. You should need to be aware of Cloud database technology like DBaaS. All Oracle DBA tips are available in a single unique resource at our orageek. Meanwhile, we are also providing some sql tutorials for Oracle DBA. This is the part of Dbametrix Group and you would enjoy more advanced topics from our partner resource.
Could you explain me how memory utilize or allocate in MySQL?
Hi Rahul,
The MySQL server is multithreaded, technically a thread is a flow of control, that is, an execution path through independent code within a process. For each client connected, the MySQL server creates a thread to manage that connection. The server maintains a cache of thread managers; when a client disconnects, the thread that managed that connection is cached if the cache is not full, in the same way when a client connects to the server, it is assigned a thread present in the cache. This management of cached threads greatly increases the performance in terms of connection and disconnection times to the database.
The MySQL server uses a series of buffers to keep the necessary information in memory to minimize the number of disk accesses. Among the buffers used by the MySQL server we find:
Orageek, could you tell me what kinds of tables supported by mySQL?
Hi Steve,
MySQL supports the following types of tables: MyISAM type tables,Tables type InnoDB, MERGE type tables, and HEAP type tables. Let me publish about this details. Please wait. You can read same on my blog.