Top 10 Hosting > Web Hosting Articles
Improve the Performance of Web Hosting
As a resource organization and expression mechanisms, Web has become the leading Internet
messaging medium. Therefore, the performance of Web sites has become a success judging an
important evaluation criteria. The Web server is an important part of the decision Web
performance.
Web server performance is defined as a Web server, the ability to respond to user
requests. In order to improve the performance of Web servers had a lot of people try to
have achieved encouraging results. Based on the analysis of the results of previous
studies, presented in the specific application environment to optimize Web servers and
strategies.
Web Server Overview
Web systems are now widely used in the network, while the Web server is a Web system, an
important component. Complete Web structure should include: HTTP protocol, Web server,
Common Gateway Interface CGI, Web Application Program Interface, Web browser.
Web server is the presence of a certain type of computer on the Internet program. It is
the information providers in the network backbone for the realization of HTTP information
release, data query, data processing, build the basic platform and many other applications
server, its main function is to provide online information browsing service. When the Web
browser (client) connected to the server and requests the file, the server will process
the request and send the file to the browser, with the information will tell the browser
how to view the file (that file type).
Web server processing in the web page can be divided into three steps: first, web browser,
a server to a particular Web page to issue requests; the second step, Web server receives
a request to the web page to find the requested web page and to send the requested Web
page to Web browser; the third step, Web server receives the requested web page, and it is
displayed.
web server can not only store information, but also in the users Web browser based on
information provided to run scripts and procedures. In the Web, most common forms are the
core search engine is used in CGI scripts.
Web application server performance impact factors
Web server performance is the means to respond to user requests a Web server capacity,
server performance is critical for a Web system. In order to improve the performance of
Web servers were a lot of people try, but also using many techniques and methods, but they
often lack the applicability of techniques and methods.
Through the analysis of previous studies can be found in the web server side and the
existence of such optimization problems for two main reasons: one is the server
performance evaluation Zaocheng, one is chosen to consider incomplete optimization scheme
caused the.
The current server performance evaluation tool for evaluation of the Web server when, in
fact, by one or several computer simulations of the client, and tested the Web server to
communicate, they are actually composed of just a LAN environment, which is true WAN
environment is somewhat different.
In addition, the evaluation tool in the choice of network load, although the load has been
as close to reality, but with the sustained high-frequency load requirements are still
gaps; Moreover, the choice of indicators in the performance testing and analysis is also
not reasonable, resulting in the analysis results were not fair and reliable. The Web
server in the selection of optimization methods often only consider one aspect of this Web
server, small light of the specific application environment. Therefore, the evaluation
results were not caused by the science, applied environmental considerations not
comprehensive, Web server performance optimization lack of specificity. Therefore, the
specific application environment to optimize the performance of Web servers require
additional consider the following two main factors: the network of Web properties and load
characteristics.
Network characteristics is the web server where the network conditions, is wide area
network or LAN, is a high-speed network (transmission speed in 1OOMb / s over the network
is called the high-speed network) or low-speed networks, different networks related to
transmission of data types, network the corresponding time, throughput, utilization and
other network characteristics is different, we should distinguish between a concrete
analysis of specific situations.
Features in the Web load, because the Web server in the evaluation, a critical factor is
the choice of Web load. Although there are a variety of evaluation tools, but they are
spared in the choice of the load on the homework. Characteristics of the load on the Web
main purpose of performance evaluation on the Web server, you can these features, select
the most realistic simulation of Web load evaluation tools in order to obtain the most
close to the facts of Web server performance evaluation data, in order to better on its
analysis and draw optimization.
Web Application Server Optimization
Optimization in the Web server when the Web application based on real situations and
characteristics to take targeted optimization. First of all, according to characteristics
of the different networks: local area network, to reduce the MTU (Maximum Transmission
Unit) value of the copied data and avoid seeking validation, and by optimizing the select
system call or the Socket event processor can perform calculations in the optimization of
concurrent requests management, persistent connection using HTTP1.1 and so can make
corresponding improvement in system performance, but in wide area network environment has
no major role, or even just the opposite.
For example: User connecting the MTU to reduce server processing overhead will increase,
with network delays, bandwidth limitations and the continued use of HTTP1.1 in the wide
area network connections on the server performance will not have any major impact. In the
wide area network, the end-user request latency and network delay depends on the degree of
limitation in the bandwidth connection. For the wide area network, software and hardware
interrupt handling in the network represents a significant component, so the interrupt
handling mechanism used to adapt to the server's response capacity will be big gains; the
server located in the kernel and will change based on process design based on Transactions
can also be improved in different degree performance of the server.
On the Web load, in addition to analyzing the characteristics of Web load in order to
better reproduce the true when evaluating the load, we should also consider the Web server
environment where the network load situation. It not only requires the server to meet the
normal work load requirements, but also in the peak is still to maintain high throughput.
However, the server under high load performance is often below expectations.
Server overload conditions are divided into two types: one for the moment of overload, the
server is temporary, short time overload, this situation is mainly caused by server load
characteristics. Many studies, Web requests from the network traffic distribution is
similar to that Web request traffic can be very significant within the scope of the
changes. This has resulted in overloading the server is often short, but it lasted a very
short time. One is the server overloaded a long time, this is usually caused by a specific
event, such as servers by Denial of Service attack or place a "live lock"
phenomenon.
The first server overload is inevitable, but the second situation can be improved by
improving the server. Not malicious attacks aside, careful analysis of the process server
process information package can be found, resulting in system performance degradation
under overload conditions the root cause is a high priority on the CPU processing stage
unfair to seize.
Therefore, if the restrictions on high-priority processing stage CPU occupancy rate, or
limiting the CPU to handle high-priority number, can reduce or eliminate receive livelock
phenomenon. Concrete can use the following method:
First, using polling mechanism. To reduce the impact on system performance disruption in
the load under normal circumstances a "semi-processing under the" method is very
effective, and in the high load condition, using this method would still cause the
phenomenon of live lock, then you can use polling mechanism. Although this method under
normal conditions in the load will cause waste of resources and response speed decreased,
but the data in the network to reach the server frequently interrupt-driven technology
than, more effectively.
Second, to reduce context switching. This approach regardless of the circumstances under
which the server performance improvements are effective, then you can use to introduce the
core level (kerne1-leve1) or hardware-level data flow approach to achieve this objective.
Core-level data stream is the data from the source transmitted through the system bus
without the need to make the data through the application process, this process because
the data in memory, requiring CPU operation data.
Hardware-level data from the source data stream sucked through the private data DMA bus,
or while such forward through the system bus without the need to make the data through the
application process, this process does not require CPU operation data. So that the data
transfer process does not require the intervention of the user thread, reducing the number
of times data is copied to reduce the overhead of context switching.
Third, reduce the frequency of interruptions (mainly methods for high loads). Here are two
ways: batch interrupts and interrupt temporarily closed. Disruption can overload approved
effective inhibition livelock phenomenon, but the performance of the server is no
fundamental improvement; When the system shows signs of receiving live lock can be
interrupted by the temporary closure of ways to ease the burden on the system, when the
system cache can be used again, re-open the interrupt, but this method is not big enough
buffer in the receiver case will cause packet loss.
Web server performance is a key link in the Web system to improve Web server performance
is a long time there has been a subject of concern. Here on the Web server through the
working principle and the optimization of existing methods and techniques of analysis,
come to the treatment of Tigao Web server performance should also analyze specific issues,
to be in specific applications in the environment, according to its features to take the
corresponding optimization measures.
web hosting explained in detailCreate a site using shared hostingsHow does web hosting affects SERP?web hosting explained in detailCreate a site using shared hostings