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  • serve static play2.x content from CDN

    - by Adam Lane
    In development mode I would like to have assets served locally and when deployed in production I would like them served from the CDN. Anyone using play2 and serving content from CDN be willing to share how they are doing it? // Thinking of something like this in the routes file... @if(play.Play.isDev()) { GET /assets/*file controllers.Assets.at(path="/public", file) } else { GET CDNPATH/assets/*file controllers.Assets.at(path="CDNPATH", file) } (Note: using 2.0.2 because of the headers fix https://github.com/playframework/Play20/pull/276)

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  • Perfect End to a Bad Day

    - by TehGrumpyCoder
    Yesterday's post about A Bad Day at Work actually had an addendum to it. There were apparently a bunch of guys on ice skates last night competing in some sport way the hell and gone over on the other side of the valley, and enough people couldn't live without seeing them that they had all major arteries heading west honked. I mean honked... the traffic guy reported the 101 had 16 miles of backup... yikes. Since I worked downtown for a number of years, my fallback is to cut across the city on surface streets to get to one of my old 'haunts' and just drive it home from there. Of course with the 101 backed up, then I17 would logically be as well, so I kept the news on rather than my Zune and heard where the bad stuff was going North. I popped out on the freeway about 7 miles south of my exit. Got to the exit which is about a mile from the house without killing or maiming me or anyone else. Waited patiently at the light in the inside lane to make a left and go under the freeway proceeding West. The light changed, I had full green, I started through and whoa... I've got someone in a little rat car crossing my bow! A little explanation... I drive a 3/4 ton pickup with a V-10, extended cab and shell on the back. It's not jacked up, but it sits up pretty good and is longer than any parking place I've ever tried to put it into. I consider this truck to be the consolation prize for paying uninsured motorist coverage for 45 years and having Pilar Martinez totally destroy a 3/4 ton Silverado on March 1, 2007 by plowing into me at traffic speed while I was stopped at a light. If you pay for uninsured motorist coverage, ask your insurance agent *exactly* what that means... I bet it's different than what you think it means. But I digress, sorry... So here I am with a car that is shorter from top to road than the hood on my truck, and the driver thought it would be safe to run a red light and see if they could get past me before I got into the lane. The right side of my front bumper was almost into the driver's window when I hit the brakes and wheeled it left. Fortunately for all involved, I saw it soon enough, and pulled into the 2nd lane for making a left to go back South. I looked in my mirror, signalled a move, then moved over behind the yuck in the rat car. I then punched it, and the future hood ornament and I both made it through the next light. I pulled alongside to let her know that she was DEFINITELY Number 1 in my book, and it's a middle-age woman looking at me with a "sorry, it was an accident" show of pouty face and arms held up. Tough $hit lady... that may have worked when you were 18, but it's not working anymore, and it wasn't an accident... you ran a freakin' red light and almost got yourself killed. That just about put a bow on the day... I was home later than usual, pissed off about work stuff, pissed off at traffic, and now that. I ate dinner, watched a little TV, and was asleep about 9:30 exhausted. Hope today is better.

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  • JMS Step 7 - How to Write to an AQ JMS (Advanced Queueing JMS) Queue from a BPEL Process

    - by John-Brown.Evans
    JMS Step 7 - How to Write to an AQ JMS (Advanced Queueing JMS) Queue from a BPEL Process ol{margin:0;padding:0} .jblist{list-style-type:disc;margin:0;padding:0;padding-left:0pt;margin-left:36pt} .c4_7{vertical-align:top;width:468pt;border-style:solid;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c3_7{vertical-align:top;width:234pt;border-style:solid;border-color:#000000;border-width:1pt;padding:0pt 5pt 0pt 5pt} .c6_7{vertical-align:top;width:156pt;border-style:solid;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c16_7{background-color:#ffffff;padding:0pt 0pt 0pt 0pt} .c0_7{height:11pt;direction:ltr} .c9_7{color:#1155cc;text-decoration:underline} .c17_7{color:inherit;text-decoration:inherit} .c5_7{direction:ltr} .c18_7{background-color:#ffff00} .c2_7{background-color:#f3f3f3} .c14_7{height:0pt} .c8_7{text-indent:36pt} .c11_7{text-align:center} .c7_7{font-style:italic} .c1_7{font-family:"Courier New"} .c13_7{line-height:1.0} .c15_7{border-collapse:collapse} .c12_7{font-weight:bold} .c10_7{font-size:8pt} .title{padding-top:24pt;line-height:1.15;text-align:left;color:#000000;font-size:36pt;font-family:"Arial";font-weight:bold;padding-bottom:6pt} .subtitle{padding-top:18pt;line-height:1.15;text-align:left;color:#666666;font-style:italic;font-size:24pt;font-family:"Georgia";padding-bottom:4pt} li{color:#000000;font-size:10pt;font-family:"Arial"} p{color:#000000;font-size:10pt;margin:0;font-family:"Arial"} h1{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:24pt;font-family:"Arial";font-weight:normal} h2{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:18pt;font-family:"Arial";font-weight:normal} h3{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:14pt;font-family:"Arial";font-weight:normal} h4{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:12pt;font-family:"Arial";font-weight:normal} h5{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:11pt;font-family:"Arial";font-weight:normal} h6{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:10pt;font-family:"Arial";font-weight:normal} This post continues the series of JMS articles which demonstrate how to use JMS queues in a SOA context. The previous posts were: JMS Step 1 - How to Create a Simple JMS Queue in Weblogic Server 11g JMS Step 2 - Using the QueueSend.java Sample Program to Send a Message to a JMS Queue JMS Step 3 - Using the QueueReceive.java Sample Program to Read a Message from a JMS Queue JMS Step 4 - How to Create an 11g BPEL Process Which Writes a Message Based on an XML Schema to a JMS Queue JMS Step 5 - How to Create an 11g BPEL Process Which Reads a Message Based on an XML Schema from a JMS Queue JMS Step 6 - How to Set Up an AQ JMS (Advanced Queueing JMS) for SOA Purposes This example demonstrates how to write a simple message to an Oracle AQ via the the WebLogic AQ JMS functionality from a BPEL process and a JMS adapter. If you have not yet reviewed the previous posts, please do so first, especially the JMS Step 6 post, as this one references objects created there. 1. Recap and Prerequisites In the previous example, we created an Oracle Advanced Queue (AQ) and some related JMS objects in WebLogic Server to be able to access it via JMS. Here are the objects which were created and their names and JNDI names: Database Objects Name Type AQJMSUSER Database User MyQueueTable Advanced Queue (AQ) Table UserQueue Advanced Queue WebLogic Server Objects Object Name Type JNDI Name aqjmsuserDataSource Data Source jdbc/aqjmsuserDataSource AqJmsModule JMS System Module AqJmsForeignServer JMS Foreign Server AqJmsForeignServerConnectionFactory JMS Foreign Server Connection Factory AqJmsForeignServerConnectionFactory AqJmsForeignDestination AQ JMS Foreign Destination queue/USERQUEUE eis/aqjms/UserQueue Connection Pool eis/aqjms/UserQueue 2 . Create a BPEL Composite with a JMS Adapter Partner Link This step requires that you have a valid Application Server Connection defined in JDeveloper, pointing to the application server on which you created the JMS Queue and Connection Factory. You can create this connection in JDeveloper under the Application Server Navigator. Give it any name and be sure to test the connection before completing it. This sample will write a simple XML message to the AQ JMS queue via the JMS adapter, based on the following XSD file, which consists of a single string element: stringPayload.xsd <?xml version="1.0" encoding="windows-1252" ?> <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"                xmlns="http://www.example.org"                targetNamespace="http://www.example.org"                elementFormDefault="qualified">  <xsd:element name="exampleElement" type="xsd:string">  </xsd:element> </xsd:schema> The following steps are all executed in JDeveloper. The SOA project will be created inside a JDeveloper Application. If you do not already have an application to contain the project, you can create a new one via File > New > General > Generic Application. Give the application any name, for example JMSTests and, when prompted for a project name and type, call the project   JmsAdapterWriteAqJms  and select SOA as the project technology type. If you already have an application, continue below. Create a SOA Project Create a new project and select SOA Tier > SOA Project as its type. Name it JmsAdapterWriteAqJms . When prompted for the composite type, choose Composite With BPEL Process. When prompted for the BPEL Process, name it JmsAdapterWriteAqJms too and choose Synchronous BPEL Process as the template. This will create a composite with a BPEL process and an exposed SOAP service. Double-click the BPEL process to open and begin editing it. You should see a simple BPEL process with a Receive and Reply activity. As we created a default process without an XML schema, the input and output variables are simple strings. Create an XSD File An XSD file is required later to define the message format to be passed to the JMS adapter. In this step, we create a simple XSD file, containing a string variable and add it to the project. First select the xsd item in the left-hand navigation tree to ensure that the XSD file is created under that item. Select File > New > General > XML and choose XML Schema. Call it stringPayload.xsd  and when the editor opens, select the Source view. then replace the contents with the contents of the stringPayload.xsd example above and save the file. You should see it under the XSD item in the navigation tree. Create a JMS Adapter Partner Link We will create the JMS adapter as a service at the composite level. If it is not already open, double-click the composite.xml file in the navigator to open it. From the Component Palette, drag a JMS adapter over onto the right-hand swim lane, under External References. This will start the JMS Adapter Configuration Wizard. Use the following entries: Service Name: JmsAdapterWrite Oracle Enterprise Messaging Service (OEMS): Oracle Advanced Queueing AppServer Connection: Use an existing application server connection pointing to the WebLogic server on which the connection factory created earlier is located. You can use the “+” button to create a connection directly from the wizard, if you do not already have one. Adapter Interface > Interface: Define from operation and schema (specified later) Operation Type: Produce Message Operation Name: Produce_message Produce Operation Parameters Destination Name: Wait for the list to populate. (Only foreign servers are listed here, because Oracle Advanced Queuing was selected earlier, in step 3) .         Select the foreign server destination created earlier, AqJmsForeignDestination (queue) . This will automatically populate the Destination Name field with the name of the foreign destination, queue/USERQUEUE . JNDI Name: The JNDI name to use for the JMS connection. This is the JNDI name of the connection pool created in the WebLogic Server.JDeveloper does not verify the value entered here. If you enter a wrong value, the JMS adapter won’t find the queue and you will get an error message at runtime. In our example, this is the value eis/aqjms/UserQueue Messages URL: We will use the XSD file we created earlier, stringPayload.xsd to define the message format for the JMS adapter. Press the magnifying glass icon to search for schema files. Expand Project Schema Files > stringPayload.xsd and select exampleElement : string . Press Next and Finish, which will complete the JMS Adapter configuration. Wire the BPEL Component to the JMS Adapter In this step, we link the BPEL process/component to the JMS adapter. From the composite.xml editor, drag the right-arrow icon from the BPEL process to the JMS adapter’s in-arrow.   This completes the steps at the composite level. 3. Complete the BPEL Process Design Invoke the JMS Adapter Open the BPEL component by double-clicking it in the design view of the composite.xml. This will display the BPEL process in the design view. You should see the JmsAdapterWrite partner link under one of the two swim lanes. We want it in the right-hand swim lane. If JDeveloper displays it in the left-hand lane, right-click it and choose Display > Move To Opposite Swim Lane. An Invoke activity is required in order to invoke the JMS adapter. Drag an Invoke activity between the Receive and Reply activities. Drag the right-hand arrow from the Invoke activity to the JMS adapter partner link. This will open the Invoke editor. The correct default values are entered automatically and are fine for our purposes. We only need to define the input variable to use for the JMS adapter. By pressing the green “+” symbol, a variable of the correct type can be auto-generated, for example with the name Invoke1_Produce_Message_InputVariable. Press OK after creating the variable. Assign Variables Drag an Assign activity between the Receive and Invoke activities. We will simply copy the input variable to the JMS adapter and, for completion, so the process has an output to print, again to the process’s output variable. Double-click the Assign activity and create two Copy rules: for the first, drag Variables > inputVariable > payload > client:process > client:input_string to Invoke1_Produce_Message_InputVariable > body > ns2:exampleElement for the second, drag the same input variable to outputVariable > payload > client:processResponse > client:result This will create two copy rules, similar to the following: Press OK. This completes the BPEL and Composite design. 4. Compile and Deploy the Composite Compile the process by pressing the Make or Rebuild icons or by right-clicking the project name in the navigator and selecting Make... or Rebuild... If the compilation is successful, deploy it to the SOA server connection defined earlier. (Right-click the project name in the navigator, select Deploy to Application Server, choose the application server connection, choose the partition on the server (usually default) and press Finish. You should see the message ----  Deployment finished.  ---- in the Deployment frame, if the deployment was successful. 5. Test the Composite Execute a Test Instance In a browser, log in to the Enterprise Manager 11g Fusion Middleware Control (EM) for your SOA installation. Navigate to SOA > soa-infra (soa_server1) > default (or wherever you deployed your composite) and click on  JmsAdapterWriteAqJms [1.0] , then press the Test button. Enter any string into the text input field, for example “Test message from JmsAdapterWriteAqJms” then press Test Web Service. If the instance is successful, you should see the same text you entered in the Response payload frame. Monitor the Advanced Queue The test message will be written to the advanced queue created at the top of this sample. To confirm it, log in to the database as AQJMSUSER and query the MYQUEUETABLE database table. For example, from a shell window with SQL*Plus sqlplus aqjmsuser/aqjmsuser SQL> SELECT user_data FROM myqueuetable; which will display the message contents, for example Similarly, you can use the JDeveloper Database Navigator to view the contents. Use a database connection to the AQJMSUSER and in the navigator, expand Queues Tables and select MYQUEUETABLE. Select the Data tab and scroll to the USER_DATA column to view its contents. This concludes this example. The following post will be the last one in this series. In it, we will learn how to read the message we just wrote using a BPEL process and AQ JMS. Best regards John-Brown Evans Oracle Technology Proactive Support Delivery

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  • Grouping on Multiple Field

    - by Nisarg Mehta
    Hi , I am generating XML file from Database as below... <?xml version = '1.0'?> <T0019> <IFTA_ACCOUNT> <IFTA_CARRIER_ID_NUMBER>705</IFTA_CARRIER_ID_NUMBER> <IFTA_LICENSE_NUMBER>631227666</IFTA_LICENSE_NUMBER> <IFTA_BASE_COUNTRY>US</IFTA_BASE_COUNTRY> <IFTA_BASE_STATE>AL</IFTA_BASE_STATE> <IFTA_STATUS_CODE>0 </IFTA_STATUS_CODE> <IFTA_STATUS_DATE>2009-01-01</IFTA_STATUS_DATE> <IFTA_ISSUE_DATE>2009-01-01</IFTA_ISSUE_DATE> <IFTA_EXPIRE_DATE>2009-12-01</IFTA_EXPIRE_DATE> <IFTA_UPDATE_DATE>2008-12-30</IFTA_UPDATE_DATE> <NAME_TYPE>LG</NAME_TYPE> <NAME>K D L TRUCKING INC</NAME> <ADDRESS_TYPE>PH</ADDRESS_TYPE> <STREET_LINE_1>200 MARTIN LANE</STREET_LINE_1> <CITY>OHATCHEE</CITY> <STATE>AL</STATE> <ZIP_CODE>36271</ZIP_CODE> <COUNTY>CALHOUN COUNTY</COUNTY> <COUNTRY>US</COUNTRY> </IFTA_ACCOUNT> <IFTA_ACCOUNT> <IFTA_CARRIER_ID_NUMBER>705</IFTA_CARRIER_ID_NUMBER> <IFTA_LICENSE_NUMBER>631227666</IFTA_LICENSE_NUMBER> <IFTA_BASE_COUNTRY>US</IFTA_BASE_COUNTRY> <IFTA_BASE_STATE>AL</IFTA_BASE_STATE> <IFTA_STATUS_CODE>0 </IFTA_STATUS_CODE> <IFTA_STATUS_DATE>2009-01-01</IFTA_STATUS_DATE> <IFTA_ISSUE_DATE>2009-01-01</IFTA_ISSUE_DATE> <IFTA_EXPIRE_DATE>2009-12-01</IFTA_EXPIRE_DATE> <IFTA_UPDATE_DATE>2008-12-30</IFTA_UPDATE_DATE> <NAME_TYPE>LG</NAME_TYPE> <NAME>K D L TRUCKING INC</NAME> <ADDRESS_TYPE>MA</ADDRESS_TYPE> <STREET_LINE_1>200 MARTIN LANE</STREET_LINE_1> <CITY>OHATCHEE</CITY> <STATE>AL</STATE> <ZIP_CODE>36271</ZIP_CODE> <COUNTRY>US</COUNTRY> </IFTA_ACCOUNT> </T0019> I have taken first two records from generated XSLT. With the use of XSLT I have tried lot to group record on basis of IFTA_LICENSE_NUMBER,IFTA_BASE_COUNTRY,IFTA_BASE_ST ATE,NAME_TYPE,ADDRESS_TYPE but i failed to generated XML like this.. <?xml version="1.0" encoding="UTF-8" ?> <T0019> <IFTA_ACCOUNT> <IFTA_CARRIER_ID_NUMBER>705</IFTA_CARRIER_ID_NUMBER> <IFTA_BASE_COUNTRY>US</IFTA_BASE_COUNTRY> <IFTA_BASE_STATE>AL</IFTA_BASE_STATE> <IFTA_LICENSE_NUMBER>631227666</IFTA_LICENSE_NUMBER> <IFTA_STATUS_CODE>0</IFTA_STATUS_CODE> <IFTA_STATUS_DATE>2009-01-01</IFTA_STATUS_DATE> <IFTA_ISSUE_DATE>2009-01-01</IFTA_ISSUE_DATE> <IFTA_EXPIRE_DATE>2009-12-01</IFTA_EXPIRE_DATE> <IFTA_UPDATE_DATE>2008-12-30</IFTA_UPDATE_DATE> <IFTA_NAME> <NAME_TYPE>LG</NAME_TYPE> <NAME>K D L TRUCKING INC</NAME> <IFTA_ADDRESS> <ADDRESS_TYPE>PH</ADDRESS_TYPE> <STREET_LINE_1>200 MARTIN LANE</STREET_LINE_1> <STREET_LINE_2 /> <CITY>OHATCHEE</CITY> <STATE>AL</STATE> <ZIP_CODE>36271</ZIP_CODE> <COUNTY>CALHOUN COUNTY</COUNTY> <COUNTRY>US</COUNTRY> </IFTA_ADDRESS> <IFTA_ADDRESS> <ADDRESS_TYPE>MA</ADDRESS_TYPE> <STREET_LINE_1>200 MARTIN LANE</STREET_LINE_1> <STREET_LINE_2 /> <CITY>OHATCHEE</CITY> <STATE>AL</STATE> <ZIP_CODE>36271</ZIP_CODE> <COUNTY /> <COUNTRY>US</COUNTRY> </IFTA_ADDRESS> </IFTA_NAME> </IFTA_ACCOUNT> </T0019>

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  • Open Cl.I just need to convert the code to using two work items in the for loop .Currentlly it uses one

    - by user1660282
    spmv_csr_scalar_kernel(const int num_rows , const int * ptr , const int * indices , const float * data , const float * x, float * y) { int row = get_global_id(0); if(row < num_rows) { float dot = 0; int row_start = ptr[row]; int row_end = ptr[row+1]; for (int jj = row_start; jj < row_end; jj++) { dot += data[jj] * x[indices[jj]]; } y[row] += dot; } } Above is the Open Cl code for multiplying a sparse matrix in CSR format with a Column vector.It uses one global work item per for loop.Can anybody help me in using two work items in each for loop.I am new to open cl and get a lot of issues if I modify even the smallest thing.Please help me.This a part of my project.I made it this parallel but I wanna make it more parallel.Please help me if you can.plzzzz A single work item executes the for loop from row_start to row_end.I want that this row or for loop is further divided into two parts each executed by a single work item.How do I go on accomplishing that? This is what I could come up with but its returning the wrong output.plzz help __kernel void mykernel(__global int* colvector,__global int* val,__global int* result,__global int* index,__global int* rowptr,__global int* sync) { __global int vals[8]={0,0,0,0,0,0,0,0}; for(int i=0;i<4;i++) { result[i]=0; } barrier(CLK_GLOBAL_MEM_FENCE); int thread_id=get_global_id(0); int warp_id=thread_id/2; int lane=(thread_id)&1; int row=warp_id; if(row<4) { int row_start = rowptr[row]; int row_end = rowptr[row+1]; vals[thread_id]=0; for (int i = row_start+lane; i<row_end; i+=2) { vals[thread_id]+=val[i]*colvector[index[i]]; } vals[thread_id]+=vals[thread_id+1]; if(lane==0){ result[row] += vals[thread_id]; } } }

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  • Week 21: FY10 in the Rear View Mirror

    - by sandra.haan
    FY10 is coming to a close and before we dive into FY11 we thought we would take a walk down memory lane and reminisce on some of our favorite Oracle PartnerNetwork activities. June 2009 brought One Red Network to partners offering access to the same virtual kickoff environment used by Oracle employees. It was a new way to deliver valuable content to key stakeholders (and without the 100+ degree temperatures). Speaking of hot, Oracle also announced in June new licensing options for our ISV partners. This model enables an even broader community of ISVs to build, deploy and manage SaaS applications on the same platform. While some people took the summer off, the OPN Program team was working away to deliver a brand new partner program - Oracle PartnerNetwork Specialized - at Oracle OpenWorld in October. Specialized. Recognized. Preferred. If you haven't gotten the message yet, we may need an emergency crew to pull you out from that rock you've been hiding under. But seriously, the announcement at the OPN Forum drew a big crowd and our FY11 event is shaping up to be just as exciting. OPN Specialized was announced in October and opened our doors for enrollment in December 2009. To mark our grand opening we held our first ever social webcast allowing partners from around the world to interact with us live throughout the day. We had a lot of great conversations and really enjoyed the chance to speak with so many of you. After a short holiday break we were back at it - just a small announcement - Oracle's acquisition of Sun. In case you missed it, here is a short field report from Ted Bereswill, SVP North America Alliances & Channels on the partner events to support the announcement: And while we're announcing things - did we mention that both Ted Bereswill and Judson Althoff were named Channel Chiefs by CRN? Not only do we have a couple of Channel Chiefs, but Oracle also won the Partner Program 5 Star Programs Award and took top honors at the CRN Channel Champion Awards for Financial Factors/Financial Performance in the category of Data and Information Management and the and Xchange Solution Provider event in March 2010. We actually caught up with Judson at this event for a quick recap of our participation: But awards aside, let's not forget our main focus in FY10 and that is Specialization. In April we announced that we had over 35 Specializations available for partners and a plan to deliver even more in FY11. We are just days away from the end of FY10 but hope you enjoyed our walk down memory lane. We are already planning lots of activity for our partners in FY11 starting with our Partner Kickoff event on June 29th. Join us to hear the vision and strategy for FY11 and interact with regional A&C leaders. We look forward to talking with you then. The OPN Communications Team

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  • A Brief History of Video Games [Video]

    - by Asian Angel
    Are you ready to take a trip down nostalgia lane? This compilation of video game footage provides a brief but interesting look at some of our favorite games over the years and how much the look and feel of them has changed. A Brief History of Video Games [via Neatorama] HTG Explains: What Is RSS and How Can I Benefit From Using It? HTG Explains: Why You Only Have to Wipe a Disk Once to Erase It HTG Explains: Learn How Websites Are Tracking You Online

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  • Oracle and Deloitte Consulting - Governance, Risk and Compliance

    Lee Dittmar, principal with Deloitte Consulting's Enterprise Governance practice; Folia Grace, Oracle's Vice President of ERP and CPM Applications Marketing; and Lane Leskela, Oracle's Senior Product Marketing Director for Governance, Risk and Compliance Applications talk with Fred about the technology issues organizations are facing around governance, risk and compliance (GRC) and Deloitte's and Oracle's approach to helping organizations achieve and sustain GRC.

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  • BPM ADF Task forms. Checking whether the current user is in a BPM Swimlane

    - by Christopher Karl Chan
    So this blog will focus on BPM Swimlane roles and users from a ADF context.So we have an ADF Task Details Form and we are in the process of making it richer and dynamic in functionality. A common requirement could be to dynamically show different areas based on the user logged into the workspace. Perhaps even we want to know even what swim-lane role the user belongs to.It is is a little bit harder to achieve then one thinks unless you know the trick. [Read More]

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  • 5 Best Practices - Laying the Foundation for WebCenter Projects

    - by Kellsey Ruppel
    Today’s guest post comes from Oracle WebCenter expert John Brunswick. John specializes in enterprise portal and content management solutions and actively contributes to the enterprise software business community and has authored a series of articles about optimal business involvement in portal, business process management and SOA development, examining ways of helping organizations move away from monolithic application development. We’re happy to have John join us today! Maximizing success with Oracle WebCenter portal requires a strategic understanding of Oracle WebCenter capabilities.  The following best practices enable the creation of portal solutions with minimal resource overhead, while offering the greatest flexibility for progressive elaboration. They are inherently project agnostic, enabling a strong foundation for future growth and an expedient return on your investment in the platform.  If you are able to embrace even only a few of these practices, you will materially improve your deployment capability with WebCenter. 1. Segment Duties Around 3Cs - Content, Collaboration and Contextual Data "Agility" is one of the most common business benefits touted by modern web platforms.  It sounds good - who doesn't want to be Agile, right?  How exactly IT organizations go about supplying agility to their business counterparts often lacks definition - hamstrung by ambiguity. Ultimately, businesses want to benefit from reduced development time to deliver a solution to a particular constituent, which is augmented by as much self-service as possible to develop and manage the solution directly. All done in the absence of direct IT involvement. With Oracle WebCenter's depth in the areas of content management, pallet of native collaborative services, enterprise mashup capability and delegated administration, it is very possible to execute on this business vision at a technical level. To realize the benefits of the platform depth we can think of Oracle WebCenter's segmentation of duties along the lines of the 3 Cs - Content, Collaboration and Contextual Data.  All three of which can have their foundations developed by IT, then provisioned to the business on a per role basis. Content – Oracle WebCenter benefits from an extremely mature content repository.  Work flow, audit, notification, office integration and conversion capabilities for documents (HTML & PDF) make this a haven for business users to take control of content within external and internal portals, custom applications and web sites.  When deploying WebCenter portal take time to think of areas in which IT can provide the "harness" for content to reside, then allow the business to manage any content items within the site, using the content foundation to ensure compliance with business rules and process.  This frees IT to work on more mission critical challenges and allows the business to respond in short order to emerging market needs. Collaboration – Native collaborative services and WebCenter spaces are a perfect match for business users who are looking to enable document sharing, discussions and social networking.  The ability to deploy the services is granular and on the basis of roles scoped to given areas of the system - much like the first C “content”.  This enables business analysts to design the roles required and IT to provision with peace of mind that users leveraging the collaborative services are only able to do so in explicitly designated areas of a site. Bottom line - business will not need to wait for IT, but cannot go outside of the scope that has been defined based on their roles. Contextual Data – Collaborative capabilities are most powerful when included within the context of business data.  The ability to supply business users with decision shaping data that they can include in various parts of a portal or portals, just as they would with content items, is one of the most powerful aspects of Oracle WebCenter.  Imagine a discussion about new store selection for a retail chain that re-purposes existing information from business intelligence services about various potential locations and or custom backend systems - presenting it directly in the context of the discussion.  If there are some data sources that are preexisting in your enterprise take a look at how they can be made into discrete offerings within the portal, then scoped to given business user roles for inclusion within collaborative activities. 2. Think Generically, Execute Specifically Constructs.  Anyone who has spent much time around me knows that I am obsessed with this word.  Why? Because Constructs offer immense power - more than APIs, Web Services or other technical capability. Constructs offer organizations the ability to leverage a platform's native characteristics to offer substantial business functionality - without writing code.  This concept becomes more powerful with the additional understanding of the concepts from the platform that an organization learns over time.  Let's take a look at an example of where an Oracle WebCenter construct can substantially reduce the time to get a subscription-based site out the door and into the hands of the end consumer. Imagine a site that allows members to subscribe to specific disciplines to access information and application data around that various discipline.  A space is a collection of secured pages within Oracle WebCenter.  Spaces are not only secured, but also default content stored within it to be scoped automatically to that space. Taking this a step further, Oracle WebCenter’s Activity Stream surfaces events, discussions and other activities that are scoped to the given user on the basis of their space affiliations.  In order to have a portal that would allow users to "subscribe" to information around various disciplines - spaces could be used out of the box to achieve this capability and without using any APIs or low level technical work to achieve this. 3. Make Governance Work for You Imagine driving down the street without the painted lines on the road.  The rules of the road are so ingrained in our minds, we often do not think about the process, but seemingly mundane lane markers are critical enablers. Lane markers allow us to travel at speeds that would be impossible if not for the agreed upon direction of flow. Additionally and more importantly, it allows people to act autonomously - going where they please at any given time. The return on the investment for mobility is high enough for people to buy into globally agreed up governance processes. In Oracle WebCenter we can use similar enablers to lane markers.  Our goal should be to enable the flow of information and provide end users with the ability to arrive at business solutions as needed, not on the basis of cumbersome processes that cannot meet the business needs in a timely fashion. How do we do this? Just as with "Segmentation of Duties" Oracle WebCenter technologies offer the opportunity to compartmentalize various business initiatives from each other within the system due to constructs and security that are available to use within the platform. For instance, when a WebCenter space is created, any content added within that space by default will be secured to that particular space and inherits meta data that is associated with a folder created for the space. Oracle WebCenter content uses meta data to support a broad range of rich ECM functionality and can automatically impart retention, workflow and other policies automatically on the basis of what has been defaulted for that space. Depending on your business needs, this paradigm will also extend to sub sections of a space, offering some interesting possibilities to enable automated management around content. An example may be press releases within a particular area of an extranet that require a five year retention period and need to the reviewed by marketing and legal before release.  The underlying content system will transparently take care of this process on the basis of the above rules, enabling peace of mind over unstructured data - which could otherwise become overwhelming. 4. Make Your First Project Your Second Imagine if Michael Phelps was competing in a swimming championship, but told right before his race that he had to use a brand new stroke.  There is no doubt that Michael is an outstanding swimmer, but chances are that he would like to have some time to get acquainted with the new stroke. New technologies should not be treated any differently.  Before jumping into the deep end it helps to take time to get to know the new approach - even though you may have been swimming thousands of times before. To quickly get a handle on Oracle WebCenter capabilities it can be helpful to deploy a sandbox for the team to use to share project documents, discussions and announcements in an effort to help the actual deployment get under way, while increasing everyone’s knowledge of the platform and its functionality that may be helpful down the road. Oracle Technology Network has made a pre-configured virtual machine available for download that can be a great starting point for this exercise. 5. Get to Know the Community If you are reading this blog post you have most certainly faced a software decision or challenge that was solved on the basis of a small piece of missing critical information - which took substantial research to discover.  Chances were also good that somewhere, someone had already come across this information and would have been excited to share it. There is no denying the power of passionate, connected users, sharing key tips around technology.  The Oracle WebCenter brand has a rich heritage that includes industry-leading technology and practitioners.  With the new Oracle WebCenter brand, opportunities to connect with these experts has become easier. Oracle WebCenter Blog Oracle Social Enterprise LinkedIn WebCenter Group Oracle WebCenter Twitter Oracle WebCenter Facebook Oracle User Groups Additionally, there are various Oracle WebCenter related blogs by an excellent grouping of services partners.

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  • Oracle Reduces Human Capital Compliance Risks

    Fred speaks with Mark Silverstein, CEO for Xcelicor, and Lane Leskela, Oracle's Senior Compliance Product Marketing Director, about the impact of Sarbanes-Oxley on Human Capital Management and how Oracle technology reduces this compliance risk.

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  • How to implement an intelligent enemy in a shoot-em-up?

    - by bummzack
    Imagine a very simple shoot-em-up, something we all know: You're the player (green). Your movement is restricted to the X axis. Our enemy (or enemies) is at the top of the screen, his movement is also restricted to the X axis. The player fires bullets (yellow) at the enemy. I'd like to implement an A.I. for the enemy that should be really good at avoiding the players bullets. My first idea was to divide the screen into discrete sections and assign weights to them: There are two weights: The "bullet-weight" (grey) is the danger imposed by a bullet. The closer the bullet is to the enemy, the higher the "bullet-weight" (0..1, where 1 is highest danger). Lanes without a bullet have a weight of 0. The second weight is the "distance-weight" (lime-green). For every lane I add 0.2 movement cost (this value is kinda arbitrary now and could be tweaked). Then I simply add the weights (white) and go to the lane with the lowest weight (red). But this approach has an obvious flaw, because it can easily miss local minima as the optimal place to go would be simply between two incoming bullets (as denoted with the white arrow). So here's what I'm looking for: Should find a way through bullet-storm, even when there's no place that doesn't impose a threat of a bullet. Enemy can reliably dodge bullets by picking an optimal (or almost optimal) solution. Algorithm should be able to factor in bullet movement speed (as they might move with different velocities). Ways to tweak the algorithm so that different levels of difficulty can be applied (dumb to super-intelligent enemies). Algorithm should allow different goals, as the enemy doesn't only want to evade bullets, he should also be able to shoot the player. That means that positions where the enemy can fire at the player should be preferred when dodging bullets. So how would you tackle this? Contrary to other games of this genre, I'd like to have only a few, but very "skilled" enemies instead of masses of dumb enemies.

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  • How to Get Noticed on the Information Highway - The Basics of SEO

    The information highway (the internet) resembles a six lane main road at rush hour. There is more and more information available every day. The question is how to stay on top of the information explosion and keep your products and services within view of your customers and also within view of new markets and potential clients.

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  • Minimum-Waste Print Job Grouping Algorithm?

    - by Matt Mc
    I work at a publishing house and I am setting up one of our presses for "ganging", in other words, printing multiple jobs simultaneously. Given that different print jobs can have different quantities, and anywhere from 1 to 20 jobs might need to be considered at a time, the problem would be to determine which jobs to group together to minimize waste (waste coming from over-printing on smaller-quantity jobs in a given set, that is). Given the following stable data: All jobs are equal in terms of spatial size--placement on paper doesn't come into consideration. There are three "lanes", meaning that three jobs can be printed simultaneously. Ideally, each lane has one job. Part of the problem is minimizing how many lanes each job is run on. If necessary, one job could be run on two lanes, with a second job on the third lane. The "grouping" waste from a given set of jobs (let's say the quantities of them are x, y and z) would be the highest number minus the two lower numbers. So if x is the higher number, the grouping waste would be (x - y) + (x - z). Otherwise stated, waste is produced by printing job Y and Z (in excess of their quantities) up to the quantity of X. The grouping waste would be a qualifier for the given set, meaning it could not exceed a certain quantity or the job would simply be printed alone. So the question is stated: how to determine which sets of jobs are grouped together, out of any given number of jobs, based on the qualifiers of 1) Three similar quantities OR 2) Two quantities where one is approximately double the other, AND with the aim of minimal total grouping waste across the various sets. (Edit) Quantity Information: Typical job quantities can be from 150 to 350 on foreign languages, or 500 to 1000 on English print runs. This data can be used to set up some scenarios for an algorithm. For example, let's say you had 5 jobs: 1000, 500, 500, 450, 250 By looking at it, I can see a couple of answers. Obviously (1000/500/500) is not efficient as you'll have a grouping waste of 1000. (500/500/450) is better as you'll have a waste of 50, but then you run (1000) and (250) alone. But you could also run (1000/500) with 1000 on two lanes, (500/250) with 500 on two lanes and then (450) alone. In terms of trade-offs for lane minimization vs. wastage, we could say that any grouping waste over 200 is excessive. (End Edit) ...Needless to say, quite a problem. (For me.) I am a moderately skilled programmer but I do not have much familiarity with algorithms and I am not fully studied in the mathematics of the area. I'm I/P writing a sort of brute-force program that simply tries all options, neglecting any option tree that seems to have excessive grouping waste. However, I can't help but hope there's an easier and more efficient method. I've looked at various websites trying to find out more about algorithms in general and have been slogging my way through the symbology, but it's slow going. Unfortunately, Wikipedia's articles on the subject are very cross-dependent and it's difficult to find an "in". The only thing I've been able to really find would seem to be a definition of the rough type of algorithm I need: "Exclusive Distance Clustering", one-dimensionally speaking. I did look at what seems to be the popularly referred-to algorithm on this site, the Bin Packing one, but I was unable to see exactly how it would work with my problem. Any help is appreciated. :)

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  • InSync12 and Australia Visits: UX is Global, Regional, Everywhere!

    - by ultan o'broin
    I attended the Australian Oracle User Group (AUSOUG) and Quest International User Group's InSync12 event in Melbourne, Australia: the user group conference for Oracle products in the ANZ region. I demoed Oracle Fusion Applications and then presented how Oracle crafted the world class Fusion Apps user experience (UX). I explained about the Oracle user experience design pattern strategy of uptake for all apps, not just Fusion, and what our UX pattern externalization strategy means for customers, partners, and ADF developers. A great conference, lots of energy, the InSync12 highlights for me were Oracle's Senior Vice President Cliff Godwin’s fast-moving Oracle E-Business Suite (EBS) roadshow with the killer Oracle Endeca user experience uptake, and Oracle ADF product outreachmeister Chris Muir’s (@chriscmuir) session on Oracle ADF Mobile solution and his hands-on mobile app development showing how existing ADF/JDev skills can build a secure, code once-deploy-to-many-device hybrid app solution in minutes. Cliff Godwin shows off the Oracle Endeca integration with Oracle E-Business Suite. Chris Muir talked the talk and then walked the walked with Oracle ADF Mobile. Applications UX was mixing it up with the crowd at InSync12 too, showing off cool mobile UX solutions, gathering data for future innovations, and engaging with EBS, JD Edwards, and PeopleSoft apps customers and partners. User conferences such as InSync12 are an important part of our Oracle Applications UX user-centered design process, giving real apps users the opportunity to make real inputs and a way for us to watch and to listen to their needs and wants and get views on current and emerging UX too. Eric Stilan (@icondaddy) of Applications UX uses an iPad to gather feedback on the latest UX designs from conference attendees. While in Melbourne, I also visited impressive Oracle partner, Callista for a major ADF and UX pow-wow, and was the er, star of a very proactive event hosted by another partner Park Lane Information Technology (coordinated by Bambi Price (@bambiprice) of ODTUG) where I explained what UX is about, and how partner and customers can engage, participate and deploy that Applications UX scientific insight to advantage for their entire business. I also paired up with Oracle Australia in Sydney to visit key customers while there, and back at Oracle in Melbourne I spoke with sales consultants and account managers about regional opportunities and UX strategy, and came away with an understanding of what makes the Oracle market tick in Australia. Mobile worker solution development and user experience is hot news in Australia, and this was a great opportunity to team up with Chris Muir and show how the alignment of the twin stars of UX design patterns and ADF technology enables developers to make great-looking, usable apps that really sparkle. Our UX design patterns--or functional (UI) patterns, to use the developer world language--means that developers now have not only a great tool set to build apps on Oracle ADF/FMW but proven, tested usability solutions to solve common problems they can apply in the IDE too. In all, a whirlwind UX visit, packed with events and delivery opportunities, and all too short a time in the wonderful city of Melbourne. I need to get back there soon! For those who need a reminder, there's a website explaining how to get involved with, and participate in, Applications User Experience (including the Oracle Usability Advisory Board) events and programs. Thank you to AUSOUG, Quest, InSync, Callista, Park Lane IT, everyone at Oracle Australia, Chris Muir, and all the other people who came together to make this a productive visit. Stay tuned for more UX developments and engagements in the region on the Oracle VoX blog and Usable Apps website too!

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  • SQLAuthority News – Random Thoughts and Random Ideas

    - by pinaldave
    There are days when I keep on wondering about SQL, and even my life overall. Today is Saturday so I decided to write about SQL Server. Just like any other mornings, I woke up at 5 and opened my blog editor. I usually do not open Twitter or Facebook when I am planning to focus on my work, as they are little distractions for me. But today I opened my Twitter account and came across a very interesting quote from a friend: ‘Can I expect you to be different today?’ Well, I think it was very powerful quote for me to read first thing on a new day. This quote froze me for a while and made me think, “Do I really want to write about an SQL Server tip, or something different?”  After a little thinking, I’ve realized that for today I would go on and write something different. I am going to write about a few of the ideas and thoughts I had yesterday. After writing all these, I realized that if I am thinking so much in a day, and if I write a blog post of my random musing of the week or month, it can be so long (and boring). Here are some of my random thoughts I’d like to share with you: When the airplane lands, why does everybody get up and try to rush out when their luggage would be coming probably 20-30 minutes later? I really do not like this question when it was asked to me: “SQL Server is not using optimal index which I just created – how can I force it?” I am not going elaborate on this statement but you are allowed to in the comment section. Why do some people wish Good Morning even when they meet us after 4 PM? Can I optimize a query so much that it gives me a result before I execute it? Is it corruption when someone does their personal household work at office? The lane where I drive is always the slowest lane. Why waste time on correcting others when there are a lot of pending improvements for ourselves? If I have to get Tattoo, which SQL Server Execution Plan symbol should I get? Why do I reach office so early that the coffee machine is yet running its daily cleaning job? Why does every laptop have a ‘Page Up’ key at different locations on the keyboard? While I like color movies, I really appreciate black and white photographs. I do not appreciate statements like, “If I receive your books in PDF, I will spread it to many people to give you much greater exposure. So would you please send them to me ASAP?” Do not tell me, “Why does the database grow back after shrinking it every day?” I suggest you use “Search this blog” for the explanation. Petrol prices are currently at INR 74. I hope the rate remains there. Let me ask you the same question which started my day today:  “Can I expect you to be different today?” Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: About Me, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • ERB Template removing the trailing line

    - by KandadaBoggu
    I have an ERB template for sending an email. Name: <%= @user.name %> <% unless @user.phone.blank? %> Phone: <%= @user.phone %> <% end %> Address: <%= @user.address %> When the user hasn't set the phone then the email body is as follows: Name: John Miller Address: X124 Dummy Lane, Dummy City, CA I am trying to remove the blank line between Name and Address when Phone is empty. Name: John Miller Address: X124 Dummy Lane, Dummy City, CA I have tried to use <%--%> tags(to remove the trailing new line) without any success. Name: <%= @user.name %> <%- unless @user.phone.blank? -%> Phone: <%= @user.phone %> <%- end -%> Address: <%= @user.address -%> How do I work around this issue?

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  • PCI-express - is there a typo in the Intel 5500 overview

    - by Martin
    The overview for the 5500 and 5520 chipsets state that there is a total bandwidth of up to 48GB/s on each PCI Express x8 interface. http://www.intel.com/products/server/chipsets/5500-5520/5500-5520-overview.htm My understanding (admittedly from wikipedia) is that PCI-e Gen 2 runs at 500MB/s per lane. The 5520 has 36 lanes, and so would be limited to a total of 18GB/s. Am I missing something here, or is Intel's claimed 48GB/s a typo that should say 18GB/s ?

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  • How to egrep the first character in second column?

    - by Steve
    using egrep, how can i print all lastnames start with K or k ??? Jennifer Cowan:548-834-2348:583 Laurel Ave., Kingsville, TX 83745:10/1/35:58900 Lesley Kirstin:408-456-1234:4 Harvard Square, Boston, MA 02133:4/22/62:52600 Jennifer Cowan:548-834-2348:583 Laurel Ave., kingsville, TX 83745:10/1/35:58900 Lesley kirstin:408-456-1234:4 Harvard Square, Boston, MA 02133:4/22/62:52600 William Kopf:846-836-2837:6937 Ware Road, Milton, PA 93756:9/21/46:43500 Arthur Putie:923-835-8745:23 Wimp Lane, Kensington, DL 38758:8/31/69:126000

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  • The Best of CES (Consumer Electronics Show) in 2011

    - by Justin Garrison
    This year, How-To Geek’s own Justin was on-site at the Consumer Electronics Show in Las Vegas, where every gadget manufacturer shows off their latest creations, and he was able to sit down and get hands-on with most of them. Here’s the best of the bunch. Make sure to also check out our list of the Worst of CES 2011, where we covered the gadgets that just didn’t make the cut Latest Features How-To Geek ETC HTG Projects: How to Create Your Own Custom Papercraft Toy How to Combine Rescue Disks to Create the Ultimate Windows Repair Disk What is Camera Raw, and Why Would a Professional Prefer it to JPG? The How-To Geek Guide to Audio Editing: The Basics How To Boot 10 Different Live CDs From 1 USB Flash Drive The 20 Best How-To Geek Linux Articles of 2010 Arctic Theme for Windows 7 Gives Your Desktop an Icy Touch Install LibreOffice via PPA and Receive Auto-Updates in Ubuntu Creative Portraits Peek Inside the Guts of Modern Electronics Scenic Winter Lane Wallpaper to Create a Relaxing Mood Access Your Web Apps Directly Using the Context Menu in Chrome The Deep – Awesome Use of Metal Objects as Deep Sea Creatures [Video]

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  • PTLQueue : a scalable bounded-capacity MPMC queue

    - by Dave
    Title: Fast concurrent MPMC queue -- I've used the following concurrent queue algorithm enough that it warrants a blog entry. I'll sketch out the design of a fast and scalable multiple-producer multiple-consumer (MPSC) concurrent queue called PTLQueue. The queue has bounded capacity and is implemented via a circular array. Bounded capacity can be a useful property if there's a mismatch between producer rates and consumer rates where an unbounded queue might otherwise result in excessive memory consumption by virtue of the container nodes that -- in some queue implementations -- are used to hold values. A bounded-capacity queue can provide flow control between components. Beware, however, that bounded collections can also result in resource deadlock if abused. The put() and take() operators are partial and wait for the collection to become non-full or non-empty, respectively. Put() and take() do not allocate memory, and are not vulnerable to the ABA pathologies. The PTLQueue algorithm can be implemented equally well in C/C++ and Java. Partial operators are often more convenient than total methods. In many use cases if the preconditions aren't met, there's nothing else useful the thread can do, so it may as well wait via a partial method. An exception is in the case of work-stealing queues where a thief might scan a set of queues from which it could potentially steal. Total methods return ASAP with a success-failure indication. (It's tempting to describe a queue or API as blocking or non-blocking instead of partial or total, but non-blocking is already an overloaded concurrency term. Perhaps waiting/non-waiting or patient/impatient might be better terms). It's also trivial to construct partial operators by busy-waiting via total operators, but such constructs may be less efficient than an operator explicitly and intentionally designed to wait. A PTLQueue instance contains an array of slots, where each slot has volatile Turn and MailBox fields. The array has power-of-two length allowing mod/div operations to be replaced by masking. We assume sensible padding and alignment to reduce the impact of false sharing. (On x86 I recommend 128-byte alignment and padding because of the adjacent-sector prefetch facility). Each queue also has PutCursor and TakeCursor cursor variables, each of which should be sequestered as the sole occupant of a cache line or sector. You can opt to use 64-bit integers if concerned about wrap-around aliasing in the cursor variables. Put(null) is considered illegal, but the caller or implementation can easily check for and convert null to a distinguished non-null proxy value if null happens to be a value you'd like to pass. Take() will accordingly convert the proxy value back to null. An advantage of PTLQueue is that you can use atomic fetch-and-increment for the partial methods. We initialize each slot at index I with (Turn=I, MailBox=null). Both cursors are initially 0. All shared variables are considered "volatile" and atomics such as CAS and AtomicFetchAndIncrement are presumed to have bidirectional fence semantics. Finally T is the templated type. I've sketched out a total tryTake() method below that allows the caller to poll the queue. tryPut() has an analogous construction. Zebra stripping : alternating row colors for nice-looking code listings. See also google code "prettify" : https://code.google.com/p/google-code-prettify/ Prettify is a javascript module that yields the HTML/CSS/JS equivalent of pretty-print. -- pre:nth-child(odd) { background-color:#ff0000; } pre:nth-child(even) { background-color:#0000ff; } border-left: 11px solid #ccc; margin: 1.7em 0 1.7em 0.3em; background-color:#BFB; font-size:12px; line-height:65%; " // PTLQueue : Put(v) : // producer : partial method - waits as necessary assert v != null assert Mask = 1 && (Mask & (Mask+1)) == 0 // Document invariants // doorway step // Obtain a sequence number -- ticket // As a practical concern the ticket value is temporally unique // The ticket also identifies and selects a slot auto tkt = AtomicFetchIncrement (&PutCursor, 1) slot * s = &Slots[tkt & Mask] // waiting phase : // wait for slot's generation to match the tkt value assigned to this put() invocation. // The "generation" is implicitly encoded as the upper bits in the cursor // above those used to specify the index : tkt div (Mask+1) // The generation serves as an epoch number to identify a cohort of threads // accessing disjoint slots while s-Turn != tkt : Pause assert s-MailBox == null s-MailBox = v // deposit and pass message Take() : // consumer : partial method - waits as necessary auto tkt = AtomicFetchIncrement (&TakeCursor,1) slot * s = &Slots[tkt & Mask] // 2-stage waiting : // First wait for turn for our generation // Acquire exclusive "take" access to slot's MailBox field // Then wait for the slot to become occupied while s-Turn != tkt : Pause // Concurrency in this section of code is now reduced to just 1 producer thread // vs 1 consumer thread. // For a given queue and slot, there will be most one Take() operation running // in this section. // Consumer waits for producer to arrive and make slot non-empty // Extract message; clear mailbox; advance Turn indicator // We have an obvious happens-before relation : // Put(m) happens-before corresponding Take() that returns that same "m" for T v = s-MailBox if v != null : s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 // unlock slot to admit next producer and consumer return v Pause tryTake() : // total method - returns ASAP with failure indication for auto tkt = TakeCursor slot * s = &Slots[tkt & Mask] if s-Turn != tkt : return null T v = s-MailBox // presumptive return value if v == null : return null // ratify tkt and v values and commit by advancing cursor if CAS (&TakeCursor, tkt, tkt+1) != tkt : continue s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 return v The basic idea derives from the Partitioned Ticket Lock "PTL" (US20120240126-A1) and the MultiLane Concurrent Bag (US8689237). The latter is essentially a circular ring-buffer where the elements themselves are queues or concurrent collections. You can think of the PTLQueue as a partitioned ticket lock "PTL" augmented to pass values from lock to unlock via the slots. Alternatively, you could conceptualize of PTLQueue as a degenerate MultiLane bag where each slot or "lane" consists of a simple single-word MailBox instead of a general queue. Each lane in PTLQueue also has a private Turn field which acts like the Turn (Grant) variables found in PTL. Turn enforces strict FIFO ordering and restricts concurrency on the slot mailbox field to at most one simultaneous put() and take() operation. PTL uses a single "ticket" variable and per-slot Turn (grant) fields while MultiLane has distinct PutCursor and TakeCursor cursors and abstract per-slot sub-queues. Both PTL and MultiLane advance their cursor and ticket variables with atomic fetch-and-increment. PTLQueue borrows from both PTL and MultiLane and has distinct put and take cursors and per-slot Turn fields. Instead of a per-slot queues, PTLQueue uses a simple single-word MailBox field. PutCursor and TakeCursor act like a pair of ticket locks, conferring "put" and "take" access to a given slot. PutCursor, for instance, assigns an incoming put() request to a slot and serves as a PTL "Ticket" to acquire "put" permission to that slot's MailBox field. To better explain the operation of PTLQueue we deconstruct the operation of put() and take() as follows. Put() first increments PutCursor obtaining a new unique ticket. That ticket value also identifies a slot. Put() next waits for that slot's Turn field to match that ticket value. This is tantamount to using a PTL to acquire "put" permission on the slot's MailBox field. Finally, having obtained exclusive "put" permission on the slot, put() stores the message value into the slot's MailBox. Take() similarly advances TakeCursor, identifying a slot, and then acquires and secures "take" permission on a slot by waiting for Turn. Take() then waits for the slot's MailBox to become non-empty, extracts the message, and clears MailBox. Finally, take() advances the slot's Turn field, which releases both "put" and "take" access to the slot's MailBox. Note the asymmetry : put() acquires "put" access to the slot, but take() releases that lock. At any given time, for a given slot in a PTLQueue, at most one thread has "put" access and at most one thread has "take" access. This restricts concurrency from general MPMC to 1-vs-1. We have 2 ticket locks -- one for put() and one for take() -- each with its own "ticket" variable in the form of the corresponding cursor, but they share a single "Grant" egress variable in the form of the slot's Turn variable. Advancing the PutCursor, for instance, serves two purposes. First, we obtain a unique ticket which identifies a slot. Second, incrementing the cursor is the doorway protocol step to acquire the per-slot mutual exclusion "put" lock. The cursors and operations to increment those cursors serve double-duty : slot-selection and ticket assignment for locking the slot's MailBox field. At any given time a slot MailBox field can be in one of the following states: empty with no pending operations -- neutral state; empty with one or more waiting take() operations pending -- deficit; occupied with no pending operations; occupied with one or more waiting put() operations -- surplus; empty with a pending put() or pending put() and take() operations -- transitional; or occupied with a pending take() or pending put() and take() operations -- transitional. The partial put() and take() operators can be implemented with an atomic fetch-and-increment operation, which may confer a performance advantage over a CAS-based loop. In addition we have independent PutCursor and TakeCursor cursors. Critically, a put() operation modifies PutCursor but does not access the TakeCursor and a take() operation modifies the TakeCursor cursor but does not access the PutCursor. This acts to reduce coherence traffic relative to some other queue designs. It's worth noting that slow threads or obstruction in one slot (or "lane") does not impede or obstruct operations in other slots -- this gives us some degree of obstruction isolation. PTLQueue is not lock-free, however. The implementation above is expressed with polite busy-waiting (Pause) but it's trivial to implement per-slot parking and unparking to deschedule waiting threads. It's also easy to convert the queue to a more general deque by replacing the PutCursor and TakeCursor cursors with Left/Front and Right/Back cursors that can move either direction. Specifically, to push and pop from the "left" side of the deque we would decrement and increment the Left cursor, respectively, and to push and pop from the "right" side of the deque we would increment and decrement the Right cursor, respectively. We used a variation of PTLQueue for message passing in our recent OPODIS 2013 paper. ul { list-style:none; padding-left:0; padding:0; margin:0; margin-left:0; } ul#myTagID { padding: 0px; margin: 0px; list-style:none; margin-left:0;} -- -- There's quite a bit of related literature in this area. I'll call out a few relevant references: Wilson's NYU Courant Institute UltraComputer dissertation from 1988 is classic and the canonical starting point : Operating System Data Structures for Shared-Memory MIMD Machines with Fetch-and-Add. Regarding provenance and priority, I think PTLQueue or queues effectively equivalent to PTLQueue have been independently rediscovered a number of times. See CB-Queue and BNPBV, below, for instance. But Wilson's dissertation anticipates the basic idea and seems to predate all the others. Gottlieb et al : Basic Techniques for the Efficient Coordination of Very Large Numbers of Cooperating Sequential Processors Orozco et al : CB-Queue in Toward high-throughput algorithms on many-core architectures which appeared in TACO 2012. Meneghin et al : BNPVB family in Performance evaluation of inter-thread communication mechanisms on multicore/multithreaded architecture Dmitry Vyukov : bounded MPMC queue (highly recommended) Alex Otenko : US8607249 (highly related). John Mellor-Crummey : Concurrent queues: Practical fetch-and-phi algorithms. Technical Report 229, Department of Computer Science, University of Rochester Thomasson : FIFO Distributed Bakery Algorithm (very similar to PTLQueue). Scott and Scherer : Dual Data Structures I'll propose an optimization left as an exercise for the reader. Say we wanted to reduce memory usage by eliminating inter-slot padding. Such padding is usually "dark" memory and otherwise unused and wasted. But eliminating the padding leaves us at risk of increased false sharing. Furthermore lets say it was usually the case that the PutCursor and TakeCursor were numerically close to each other. (That's true in some use cases). We might still reduce false sharing by incrementing the cursors by some value other than 1 that is not trivially small and is coprime with the number of slots. Alternatively, we might increment the cursor by one and mask as usual, resulting in a logical index. We then use that logical index value to index into a permutation table, yielding an effective index for use in the slot array. The permutation table would be constructed so that nearby logical indices would map to more distant effective indices. (Open question: what should that permutation look like? Possibly some perversion of a Gray code or De Bruijn sequence might be suitable). As an aside, say we need to busy-wait for some condition as follows : "while C == 0 : Pause". Lets say that C is usually non-zero, so we typically don't wait. But when C happens to be 0 we'll have to spin for some period, possibly brief. We can arrange for the code to be more machine-friendly with respect to the branch predictors by transforming the loop into : "if C == 0 : for { Pause; if C != 0 : break; }". Critically, we want to restructure the loop so there's one branch that controls entry and another that controls loop exit. A concern is that your compiler or JIT might be clever enough to transform this back to "while C == 0 : Pause". You can sometimes avoid this by inserting a call to a some type of very cheap "opaque" method that the compiler can't elide or reorder. On Solaris, for instance, you could use :"if C == 0 : { gethrtime(); for { Pause; if C != 0 : break; }}". It's worth noting the obvious duality between locks and queues. If you have strict FIFO lock implementation with local spinning and succession by direct handoff such as MCS or CLH,then you can usually transform that lock into a queue. Hidden commentary and annotations - invisible : * And of course there's a well-known duality between queues and locks, but I'll leave that topic for another blog post. * Compare and contrast : PTLQ vs PTL and MultiLane * Equivalent : Turn; seq; sequence; pos; position; ticket * Put = Lock; Deposit Take = identify and reserve slot; wait; extract & clear; unlock * conceptualize : Distinct PutLock and TakeLock implemented as ticket lock or PTL Distinct arrival cursors but share per-slot "Turn" variable provides exclusive role-based access to slot's mailbox field put() acquires exclusive access to a slot for purposes of "deposit" assigns slot round-robin and then acquires deposit access rights/perms to that slot take() acquires exclusive access to slot for purposes of "withdrawal" assigns slot round-robin and then acquires withdrawal access rights/perms to that slot At any given time, only one thread can have withdrawal access to a slot at any given time, only one thread can have deposit access to a slot Permissible for T1 to have deposit access and T2 to simultaneously have withdrawal access * round-robin for the purposes of; role-based; access mode; access role mailslot; mailbox; allocate/assign/identify slot rights; permission; license; access permission; * PTL/Ticket hybrid Asymmetric usage ; owner oblivious lock-unlock pairing K-exclusion add Grant cursor pass message m from lock to unlock via Slots[] array Cursor performs 2 functions : + PTL ticket + Assigns request to slot in round-robin fashion Deconstruct protocol : explication put() : allocate slot in round-robin fashion acquire PTL for "put" access store message into slot associated with PTL index take() : Acquire PTL for "take" access // doorway step seq = fetchAdd (&Grant, 1) s = &Slots[seq & Mask] // waiting phase while s-Turn != seq : pause Extract : wait for s-mailbox to be full v = s-mailbox s-mailbox = null Release PTL for both "put" and "take" access s-Turn = seq + Mask + 1 * Slot round-robin assignment and lock "doorway" protocol leverage the same cursor and FetchAdd operation on that cursor FetchAdd (&Cursor,1) + round-robin slot assignment and dispersal + PTL/ticket lock "doorway" step waiting phase is via "Turn" field in slot * PTLQueue uses 2 cursors -- put and take. Acquire "put" access to slot via PTL-like lock Acquire "take" access to slot via PTL-like lock 2 locks : put and take -- at most one thread can access slot's mailbox Both locks use same "turn" field Like multilane : 2 cursors : put and take slot is simple 1-capacity mailbox instead of queue Borrow per-slot turn/grant from PTL Provides strict FIFO Lock slot : put-vs-put take-vs-take at most one put accesses slot at any one time at most one put accesses take at any one time reduction to 1-vs-1 instead of N-vs-M concurrency Per slot locks for put/take Release put/take by advancing turn * is instrumental in ... * P-V Semaphore vs lock vs K-exclusion * See also : FastQueues-excerpt.java dice-etc/queue-mpmc-bounded-blocking-circular-xadd/ * PTLQueue is the same as PTLQB - identical * Expedient return; ASAP; prompt; immediately * Lamport's Bakery algorithm : doorway step then waiting phase Threads arriving at doorway obtain a unique ticket number Threads enter in ticket order * In the terminology of Reed and Kanodia a ticket lock corresponds to the busy-wait implementation of a semaphore using an eventcount and a sequencer It can also be thought of as an optimization of Lamport's bakery lock was designed for fault-tolerance rather than performance Instead of spinning on the release counter, processors using a bakery lock repeatedly examine the tickets of their peers --

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