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Date: March 1, 2012 Creator: Ilias, Shayerah Description: The proposed Anti-Counterfeiting Trade Agreement (ACTA) is a new agreement for combating intellectual property rights (IPR) infringement. The ACTA negotiation concluded in October 2010, nearly three years after it began, and negotiating parties released a final ... |
Union and its 27 member states, Japan, South Korea, Mexico, Morocco, New Zealand, Singapore, and Switzerland, the ACTA is intended to build on the IPR protection and enforcement obligations set forth in the 1995 World Trade Organization (WTO) Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS Agr... |
Date: November 17, 2005 Creator: Hanrahan, Charles E. Description: In May 2003, the United States, Canada, and Argentina initiated a formal challenge before the World Trade Organization (WTO) of the European Union’s (EU’s) de facto moratorium on approving new agricultural biotechnology products, in place since 1998. Al... |
lifted the moratorium in May 2004 by approving a genetically engineered (GE) corn variety, the three countries are pursuing the case, in part because a number of EU member states continue to block approved biotech products. Because of delays, the WTO is expected to decide the case by December 2005. |
The moratorium reportedly cost U.S. corn growers some $300 million in exports to the EU annually. The EU moratorium, U.S. officials contend, threatened other agricultural exports not only to the EU, but also to other parts of the world where the EU approach to regulating agricultural biotechnology is taking hold. |
Date: January 10, 2011 Creator: Ahearn, Raymond J. Description: Seventeen of the European Union's 27 member states share an economic and monetary union (EMU) with the euro as a single currency. These countries are effectively referred to as the Eurozone. What has become known as the Eurozone crisis began in early 2010 ... |
of a number of Eurozone countries, beginning with Greece, were unsustainable. This report provides background information and analysis on the future of the Eurozone in six parts, including discussions on the origins and design challenges of the Eurozone, proposals to define the Eurozone crisis, possible scenarios for t... |
I read a very interesting piece in today’s Philadelphia Inquirer about the history of violence in America: Violence Vanquished. Here’s just one part of it: An even more intractable debate |
accompanied the rise and fall of lynching, one of the most gruesome forms of violence ever to take root in the United States. Today, we tend to remember lynching as |
a clandestine crime – a young black man pulled from his bed in the dark of night and brutalized or hanged in the Southern woods. For most of the late |
19th and early 20th centuries, though, it was a community phenomenon of almost unthinkable cruelty, in which hundreds if not thousands of people gathered to watch a victim being disemboweled, |
castrated, tortured, or burned, and then killed. To modern sensibilities, the injustice once again seems obvious, as do the solutions: Prosecute lynchers, fight for racial justice, strengthen the rule of |
law, and mobilize public opinion to condemn rather than excuse outbursts of brutality. And yet it took more than 100 years for lynching to begin to disappear from American life, |
and even longer for Americans to fully acknowledge its horror. In the meantime, thousands of influential people, including many esteemed lawmakers, argued that lynching was a fact of life, a |
random act of violence about which nothing could be done. It was not until 2005 that the U.S. Senate, spearheaded by Mary Landrieu, apologized for failing to pass federal antilynching |
Free for educational use World Wide Web Year of production - 2005 Duration - 2min 10sec Tags - Internet, World Wide Web, design, emerging technologies, innovation, technology, technology and society, web protocols, web standards, see all tags On this Page How to Download the Video Clip About the Video Cliptop |
This interview with Stephen Mayne was recorded for the website From Wireless to Web, produced in 2005. Stephen Mayne is the founder and editor of independent news service crikey.com. You can view his full biography at From Wireless to Web The website is a selective history of broadcast media in |
Australia. Decade by decade, from radio and newsreels to TV and the internet, this history shows how the Australian broadcast media developed and shaped the way Australians see themselves. From Wireless to Web is a Film Australia production in association with Roar Film. This Module can be used to achieve |
some of outcomes of the NSW Information Processes and Technology Stage 6 syllabus; specifically the following outcomes: P4.1: describes the historical development of information systems and relates these to current and emerging technologies. H3.1: evaluates the effect of information systems on the individual, society a... |
in which information systems will meet emerging needs. The advent of the World Wide Web radically changed the online experience. At last information could be interpreted and displayed in a standardised form across the vast 'web’ of different computer networks. Cyberspace was transformed, appearing as a seamless global ... |
enabling users anywhere to search, browse and interact. Now the Internet and Web are redefining the nature of human communication, and challenging traditional limits to human relationships and communities. World Wide Web “What we are building now is the nervous system of mankind, which will link together the whole huma... |
race, for better or for worse, in a unity which no earlier age could have imagined.” (Arthur C Clarke, science fiction writer, Voices From the Sky, 1965) The Internet is a communications system formed by the interconnecting networks of computers around the world. But before the advent of the World |
Web pages can include text, graphics and images, videos and sound. In November 2004 Google claimed to cover 8,058,044,651 web pages. (Wikipedia 'Size Comparisons’) The web uses a special language and set of rules to create 'web pages’ – primarily Hyper Text Markup Language (HTML) and the Hyper Text Transfer |
and interact. The World Wide Web was 'invented’ in 1989 by British-born Tim Berners-Lee when he wrote the first 'web browser’ – software to interpret and display HTML (hyper text mark-up language) – thereby making the coded material on a multitude of different computers and operating systems uniformly readable in |
plain English. Berners-Lee was working at CERN, the European Particle Physics Laboratory based in Switzerland at the time. As the international physics community used a diverse range of information systems and computer networks, Berners-Lee wanted to create an efficient way for the different networks to interconnect, s... |
the international organisation founded by Tim Berners-Lee that works on developing protocols and guidelines that ensure long-term growth for the web. Since 1994, W3C has produced more than ninety web standards, called W3C Recommendations that contribute to web interoperability. Develop a biography about Tim Berners-Lee... |
- Web applications and dynamic web sites were major developments in the types of interactions that can occur on the web. One simple example is the use of ‘cookies’ to remember details about users so that on return to a specific site it is tailored to the needs of that |
user. The ability to search within websites is another example. It also enabled cost effective subscription based services such as Stephen Mayne’s niche website Crikey. The ability to develop ‘smarter’ and more personalised sites as well as providing an interface that allowed customers to access information/services vi... |
greater incentive for individuals and organisations to use the web. Outline the advantages and disadvantages of web services. - Imagine you have volunteered as an AID worker in a developing country. The community in which you are working will soon have its first computer and internet access. Your role BEFORE |
the computer arrives is to explain to the community leaders how the internet works and the possible benefits for their community. Prepare what you are going to say. Rehearse your explanation in front of the class. Go to From Wireless to Web for more about the history of broadcast media |
system. For example, on Linux an Oracle background process is a Linux process. On Windows, an Oracle background process is a thread of execution within a process. Code modules are run by processes. All connected Oracle Database users must run |
the following modules to access a database instance: Application or Oracle Database utility A database user runs a database application, such as a precompiler program or a database tool such as SQL*Plus, that issues SQL statements to a database. Oracle |
database code Each user has Oracle database code executing on his or her behalf that interprets and processes the application's SQL statements. A process normally runs in its own private memory area. Most processes can periodically write to an associated |
trace file (see "Trace Files"). Multiple-process Oracle (also called multiuser Oracle) uses several processes to run different parts of the Oracle Database code and additional processes for the users—either one process for each connected user or one or more processes |
shared by multiple users. Most databases are multiuser because a primary advantages of a database is managing data needed by multiple users simultaneously. Each process in a database instance performs a specific job. By dividing the work of the database |
and applications into several processes, multiple users and applications can connect to an instance simultaneously while the system gives good performance. A database instance contains or interacts with the following types of processes: Client processes run the application or Oracle |
tool code. Oracle processes run the Oracle database code. Oracle processes including the following subtypes: Background processes start with the database instance and perform maintenance tasks such as performing instance recovery, cleaning up processes, writing redo buffers to disk, and |
so on. Server processes perform work based on a client request. Note:Server processes, and the process memory allocated in these processes, run in the instance. The instance continues to function when server processes terminate. Slave processes perform additional tasks for |
a background or server process. The process structure varies depending on the operating system and the choice of Oracle Database options. For example, the code for connected users can be configured for dedicated server or shared server connections. In a |
shared server architecture, each server process that runs database code can serve multiple client processes. Figure 15-1 shows a system global area (SGA) and background processes using dedicated server connections. For each user connection, the application is run by a |
client process that is different from the dedicated server process that runs the database code. Each client process is associated with its own server process, which has its own program global area (PGA). When a user runs an application such |
as a Pro*C program or SQL*Plus, the operating system creates a client process (sometimes called a user process) to run the user application. The client application has Oracle Database libraries linked into it that provide the APIs required to communicate |
with the database. Client processes differ in important ways from the Oracle processes interacting directly with the instance. The Oracle processes servicing the client process can read from and write to the SGA, whereas the client process cannot. A client |
process can run on a host other than the database host, whereas Oracle processes cannot. For example, assume that a user on a client host starts SQL*Plus and connects over the network to database sample on a different host (the |
grep -e sample -e sqlplus | grep -v grep clientuser 29437 29436 0 15:40 pts/1 00:00:00 sqlplus as sysdba On the database host, a search of the processes for either sample shows a server process with a nonlocal connection, but |
no client process: % ps -ef | grep -e sample -e sqlplus | grep -v grep serveruser 29441 1 0 15:40 ? 00:00:00 oraclesample (LOCAL=NO) A connection is a physical communication pathway between a client process and a database instance. |
A communication pathway is established using available interprocess communication mechanisms or network software. Typically, a connection occurs between a client process and a server process or dispatcher, but it can also occur between a client process and Oracle Connection Manager |
(CMAN). A session is a logical entity in the database instance memory that represents the state of a current user login to a database. For example, when a user is authenticated by the database with a password, a session is |
established for this user. A session lasts from the time the user is authenticated by the database until the time the user disconnects or exits the database application. A single connection can have 0, 1, or more sessions established on |
it. The sessions are independent: a commit in one session does not affect transactions in other sessions. Note:If Oracle Net connection pooling is configured, then it is possible for a connection to drop but leave the sessions intact. Multiple sessions |
can exist concurrently for a single database user. As shown in Figure 15-2, user hr can have multiple connections to a database. In dedicated server connections, the database creates a server process on behalf of each connection. Only the client |
process that causes the dedicated server to be created uses it. In a shared server connection, many client processes access a single shared server process. Figure 15-3 illustrates a case in which user hr has a single connection to a |
database, but this connection has two sessions. Generating an autotrace report of SQL statement execution statistics re-creates the scenario in Figure 15-3. Example 15-2 connects SQL*Plus to the database as user SYSTEM and enables tracing, thus creating a new session |
SERIAL# PADDR --- ------- -------- 88 93 3BE2E41C 90 91 3BE2E41C ... SQL> DISCONNECT DISCONNECT command in Example 15-1 actually ends the sessions, not the connection. Opening a new terminal and connecting to the instance as a different user, the |
created on behalf of a database application can perform one or more of the following tasks: Execute PL/SQL code Read data blocks from data files into the database buffer cache (the DBWn background process has the task of writing modified |
blocks back to disk) Return results in such a way that the application can process the information In dedicated server connections, the client connection is associated with one and only one server process (see "Dedicated Server Architecture"). On Linux, 20 |
client processes connected to a database instance are serviced by 20 server processes. Each client process communicates directly with its server process. This server process is dedicated to its client process for the duration of the session. The server process |
stores process-specific information and the UGA in its PGA (see "PGA Usage in Dedicated and Shared Server Modes"). In shared server connections, client applications connect over a network to a dispatcher process, not a server process (see "Shared Server Architecture"). |
For example, 20 client processes can connect to a single dispatcher process. The dispatcher process receives requests from connected clients and puts them into a request queue in the large pool (see "Large Pool"). The first available shared server process |
takes the request from the queue and processes it. Afterward, the shared server place the result into the dispatcher response queue. The dispatcher process monitors this queue and transmits the result to the client. Like a dedicated server process, a |
shared server process has its own PGA. However, the UGA for a session is in the SGA so that any shared server can access session data. A multiprocess Oracle database uses some additional processes called background processes. The background processes |
perform maintenance tasks required to operate the database and to maximize performance for multiple users. Each background process has a separate task, but works with the other processes. For example, the LGWR process writes data from the redo log buffer |
to the online redo log. When a filled log file is ready to be archived, LGWR signals another process to archive the file. Oracle Database creates background processes automatically when a database instance starts. An instance can have many background |
processes, not all of which always exist in every database configuration. The following query lists the background processes running on your database: SELECT PNAME FROM V$PROCESS WHERE PNAME IS NOT NULL ORDER BY PNAME; This section includes the following topics: |
See Also:Oracle Database Reference for descriptions of all the background processes The mandatory background processes are present in all typical database configurations. These processes run by default in a database instance started with a minimally configured initialization parameter file (see |
Example 13-1). This section describes the following mandatory background processes: Oracle Database Reference for descriptions of other mandatory processes, including MMAN, DIAG, VKTM, DBRM, and PSP0 Oracle Real Application Clusters Administration and Deployment Guide and Oracle Clusterware Administration and Deploymen... |
Guide for more information about background processes specific to Oracle RAC and Oracle Clusterware The process monitor (PMON) monitors the other background processes and performs process recovery when a server or dispatcher process terminates abnormally. PMON is responsible for cleaning |
up the database buffer cache and freeing resources that the client process was using. For example, PMON resets the status of the active transaction table, releases locks that are no longer required, and removes the process ID from the list |
of active processes. PMON also registers information about the instance and dispatcher processes with the Oracle Net listener (see "The Oracle Net Listener"). When an instance starts, PMON polls the listener to determine whether it is running. If the listener |
is running, then PMON passes it relevant parameters. If it is not running, then PMON periodically attempts to contact it. The system monitor process (SMON) is in charge of a variety of system-level cleanup duties. The duties assigned to SMON |
include: Recovering terminated transactions that were skipped during instance recovery because of file-read or tablespace offline errors. SMON recovers the transactions when the tablespace or file is brought back online. Cleaning up unused temporary segments. For example, Oracle Database allocates |
extents when creating an index. If the operation fails, then SMON cleans up the temporary space. Coalescing contiguous free extents within dictionary-managed tablespaces. SMON checks regularly to see whether it is needed. Other processes can call SMON if they detect |
a need for it. The database writer process (DBWn) writes the contents of database buffers to data files. DBWn processes write modified buffers in the database buffer cache to disk (see "Database Buffer Cache"). Although one database writer process (DBW0) |
is adequate for most systems, you can configure additional processes—DBW1 through DBW9 and DBWa through DBWj—to improve write performance if your system modifies data heavily. These additional DBWn processes are not useful on uniprocessor systems. The DBWn process writes dirty |
buffers to disk under the following conditions: When a server process cannot find a clean reusable buffer after scanning a threshold number of buffers, it signals DBWn to write. DBWn writes dirty buffers to disk asynchronously if possible while performing |
other processing. DBWn periodically writes buffers to advance the checkpoint, which is the position in the redo thread from which instance recovery begins (see "Overview of Checkpoints"). The log position of the checkpoint is determined by the oldest dirty buffer |
in the buffer cache. In many cases the blocks that DBWn writes are scattered throughout the disk. Thus, the writes tend to be slower than the sequential writes performed by LGWR. DBWn performs multiblock writes when possible to improve efficiency. |
The number of blocks written in a multiblock write varies by operating system. See Also:Oracle Database Performance Tuning Guide for advice on configuring, monitoring, and tuning DBWn The log writer process (LGWR) manages the redo log buffer. LGWR writes one |
contiguous portion of the buffer to the online redo log. By separating the tasks of modifying database buffers, performing scattered writes of dirty buffers to disk, and performing fast sequential writes of redo to disk, the database improves performance. In |
the following circumstances, LGWR writes all redo entries that have been copied into the buffer since the last time it wrote: A user commits a transaction (see "Committing Transactions"). An online redo log switch occurs. Three seconds have passed since |
LGWR last wrote. The redo log buffer is one-third full or contains 1 MB of buffered data. DBWn must write modified buffers to disk. Before DBWn can write a dirty buffer, redo records associated with changes to the buffer must |
be written to disk (the write-ahead protocol). If DBWn finds that some redo records have not been written, it signals LGWR to write the records to disk and waits for LGWR to complete before writing the data buffers to disk. |
Oracle Database uses a fast commit mechanism to improve performance for committed transactions. When a user issues a COMMIT statement, the transaction is assigned a system change number (SCN). LGWR puts a commit record in the redo log buffer and |
writes it to disk immediately, along with the commit SCN and transaction's redo entries. The redo log buffer is circular. When LGWR writes redo entries from the redo log buffer to an online redo log file, server processes can copy |
new entries over the entries in the redo log buffer that have been written to disk. LGWR normally writes fast enough to ensure that space is always available in the buffer for new entries, even when access to the online |
redo log is heavy. The atomic write of the redo entry containing the transaction's commit record is the single event that determines the transaction has committed. Oracle Database returns a success code to the committing transaction although the data buffers |
have not yet been written to disk. The corresponding changes to data blocks are deferred until it is efficient for DBWn to write them to the data files. Note:LGWR can write redo log entries to disk before a transaction commits. |
The redo entries become permanent only if the transaction later commits. When activity is high, LGWR can use group commits. For example, a user commits, causing LGWR to write the transaction's redo entries to disk. During this write other users |
commit. LGWR cannot write to disk to commit these transactions until its previous write completes. Upon completion, LGWR can write the list of redo entries of waiting transactions (not yet committed) in one operation. In this way, the database minimizes |
disk I/O and maximizes performance. If commits requests continue at a high rate, then every write by LGWR can contain multiple commit records. LGWR writes synchronously to the active mirrored group of online redo log files. If a log file |
is inaccessible, then LGWR continues writing to other files in the group and writes an error to the LGWR trace file and the alert log. If all files in a group are damaged, or if the group is unavailable because |
it has not been archived, then LGWR cannot continue to function. Oracle Database Performance Tuning Guide for information about how to monitor and tune the performance of LGWR The checkpoint process (CKPT) updates the control file and data file headers |
with checkpoint information and signals DBWn to write blocks to disk. Checkpoint information includes the checkpoint position, SCN, location in online redo log to begin recovery, and so on. As shown in Figure 15-4, CKPT does not write data blocks |
to data files or redo blocks to online redo log files. See Also:"Overview of Checkpoints" The manageability monitor process (MMON) performs many tasks related to the Automatic Workload Repository (AWR). For example, MMON writes when a metric violates its threshold |
value, taking snapshots, and capturing statistics value for recently modified SQL objects. The manageability monitor lite process (MMNL) writes statistics from the Active Session History (ASH) buffer in the SGA to disk. MMNL writes to disk when the ASH buffer |
is full. In a distributed database, the recoverer process (RECO) automatically resolves failures in distributed transactions. The RECO process of a node automatically connects to other databases involved in an in-doubt distributed transaction. When RECO reestablishes a connection between the |
databases, it automatically resolves all in-doubt transactions, removing from each database's pending transaction table any rows that correspond to the resolved transactions. See Also:Oracle Database Administrator's Guide for more information about transaction recovery in distributed systems An optional background proc... |
is any background process not defined as mandatory. Most optional background processes are specific to tasks or features. For example, background processes that support Oracle Streams Advanced Queuing (AQ) or Oracle Automatic Storage Management (Oracle ASM) are only available when |
these features are enabled. This section describes some common optional processes: The archiver processes (ARCn) copy online redo log files to offline storage after a redo log switch occurs. These processes can also collect transaction redo data and transmit it |
to standby database destinations. ARCn processes exist only when the database is in ARCHIVELOG mode and automatic archiving is enabled. Oracle Database uses job queue processes to run user jobs, often in batch mode. A job is a user-defined task |
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