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  • Brighton Rocks: UA Europe 2011

    - by ultan o'broin
    User Assistance Europe 2011 was held in Brighton, UK. Having seen Quadrophenia a dozen times, I just had to go along (OK, I wanted to talk about messages in enterprise applications). Sadly, it rained a lot, though that was still eminently more tolerable than being stuck home in Dublin during Bloomsday. So, here are my somewhat selective highlights and observations from the conference, massively skewed towards my own interests, as usual. Enjoyed Leah Guren's (Cow TC) great start ‘keynote’ on the Cultural Dimensions of Software Help Usage. Starting out by revisiting Hofstede's and Hall's work on culture (how many times I have done this for Multilingual magazine?) and then Neilsen’s findings on age as an indicator of performance, Leah showed how it is the expertise of the user that user assistance (UA) needs to be designed for (especially for high-end users), with some considerations made for age, while the gender and culture of users are not major factors. Help also needs to be contextual and concise, embedded close to the action. That users are saying things like “If I want help on Office, I go to Google ” isn't all that profound at this stage, but it is always worth reiterating how search can be optimized to return better results for users. Interestingly, regardless of user education level, the issue of information quality--hinging on the lynchpin of terminology reflecting that of the user--is critical. Major takeaway for me there. Matthew Ellison’s sessions on embedded help and demos were also impressive. Embedded help that is concise and contextual is definitely a powerful UX enabler, and I’m pleased to say that in Oracle Fusion Applications we have embraced the concept fully. Matthew also mentioned in his session about successful software demos that the principle of modality with demos is a must. Look no further than Oracle User Productivity Kit demos See It!, Try It!, Know It, and Do It! modes, for example. I also found some key takeaways in the presentation by Marie-Louise Flacke on notes and warnings. Here, legal considerations seemed to take precedence over providing any real information to users. I was delighted when Marie-Louise called out the Oracle JDeveloper documentation as an exemplar of how to use notes and instructions instead of trying to scare the bejaysus out of people and not providing them with any real information they’d find useful instead. My own session on designing messages for enterprise applications was well attended. Knowing your user profiles (remember user expertise is the king maker for UA so write for each audience involved), how users really work, the required application business and UI rules, what your application technology supports, and how messages integrate with the enterprise help desk and support policies and you will go much further than relying solely on the guideline of "writing messages in plain language". And, remember the value in warnings and confirmation messages too, and how you can use them smartly. I hope y’all got something from my presentation and from my answers to questions afterwards. Ellis Pratt stole the show with his presentation on applying game theory to software UA, using plenty of colorful, relevant examples (check out the Atlassian and DropBox approaches, for example), and striking just the right balance between theory and practice. Completely agree that the approach to take here is not to make UA itself a game, but to invoke UA as part of a bigger game dynamic (time-to-task completion, personal and communal goals, personal achievement and status, and so on). Sure there are gotchas and limitations to gamification, and we need to do more research. However, we'll hear a lot more about this subject in coming years, particularly in the enterprise space. I hope. I also heard good things about the different sessions about DITA usage (including one by Sonja Fuga that clearly opens the door for major innovation in the community content space using WordPress), the progressive disclosure of information (Cerys Willoughby), an overview of controlled language (or "information quality", as I like to position it) solutions and rationale by Dave Gash, and others. I also spent time chatting with Mike Hamilton of MadCap Software, who showed me a cool demo of their Flare product, and the Lingo translation solution. I liked the idea of their licensing model for workers-on-the-go; that’s smart UX-awareness in itself. Also chatted with Julian Murfitt of Mekon about uptake of DITA in the enterprise space. In all, it's worth attending UA Europe. I was surprised, however, not to see conference topics about mobile UA, community conversation and content, and search in its own right. These are unstoppable forces now, and the latter is pretty central to providing assistance now to all but the most irredentist of hard-copy fetishists or advanced technical or functional users working away on the back end of applications and systems. Only saw one iPad too (says the guy who carries three laptops). Tweeting during the conference was pretty much nonexistent during the event, so no community energy there. Perhaps all this can be addressed next year. I would love to see the next UA Europe event come to Dublin (despite Bloomsday, it's not a bad place place, really) now that hotels are so cheap and all. So, what is my overall impression of the state of user assistance in Europe? Clearly, there are still many people in the industry who feel there is something broken with the traditional forms of user assistance (particularly printed doc) and something needs to be done about it. I would suggest they move on and try and embrace change, instead. Many others see new possibilities, offered by UX and technology, as well as the reality of online user behavior in an increasingly connected world and that is encouraging. Such thought leaders need to be listened to. As Ellis Pratt says in his great book, Trends in Technical Communication - Rethinking Help: “To stay relevant means taking a new perspective on the role (of technical writer), and delivering “products” over and above the traditional manual and online Help file... there are a number of new trends in this field - some complementary, some conflicting. Whatever trends emerge as the norm, it’s likely the status quo will change.” It already has, IMO. I hear similar debates in the professional translation world about the onset of translation crowd sourcing (the Facebook model) and machine translation (trust me, that battle is over). Neither of these initiatives has put anyone out of a job and probably won't, though the nature of the work might change. If anything, such innovations have increased the overall need for professional translators as user expectations rise, new audiences emerge, and organizations need to collate and curate user-generated content, combining it with their own. Perhaps user assistance professionals can learn from other professions and grow accordingly.

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  • Penguin's HPC Waddle

    Server Snapshot: Penguin Computing has always, as its name implies, focused on developing best practices for Linux-based systems, software and services, particularly in the HPC space.

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  • Penguin's HPC Waddle

    Server Snapshot: Penguin Computing has always, as its name implies, focused on developing best practices for Linux-based systems, software and services, particularly in the HPC space.

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  • Scanner Review: HP Scanjet Professional 1000

    Your notebook computer's newest companion: a $249 ultraportable scanner that takes next to no briefcase space to turn double-sided documents, images, and business cards into PDFs, e-mails, and Outlook entries. We put the peripatetic peripheral to the test.

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  • Scanner Review: HP Scanjet Professional 1000

    Your notebook computer's newest companion: a $249 ultraportable scanner that takes next to no briefcase space to turn double-sided documents, images, and business cards into PDFs, e-mails, and Outlook entries. We put the peripatetic peripheral to the test.

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  • ... i just avoid GUID

    - by Tomaz.tsql
    Our partner was explaining to me that they are using GUID as primary key on all the tables. My immediate reaction was - why? and couple of basic doubts were: - since I can read uniqueidentifier, it does not tell me absolutely anything - if I will use my relational table, i sure will use other columns to get the information out - SQL is terrible when setting up clustered index on GUID columns (and hence performance problems) - why not use INT? it will save you space on disk, optimizer will be able...(read more)

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  • Did You Know Gaming Delves into the Mario Universe [Video]

    - by Jason Fitzpatrick
    If you thought you knew everything there was to know about the Mario franchise, prepare to be surprised by the odd and expansive trivia dug up by Did You Know Gaming. Who knew you could learn so much about a game by picking through the game code for odds and ends? If you enjoyed the above video, make sure to check out Part II here. [via Geeks Are Sexy] 7 Ways To Free Up Hard Disk Space On Windows HTG Explains: How System Restore Works in Windows HTG Explains: How Antivirus Software Works

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  • 11 Ubuntu One Features You May Not Be Aware Of

    - by Chris Hoffman
    While Ubuntu One might seem like a Ubuntu-only file synchronization service, it’s more than that – you can use Ubuntu One on Windows, Android, iOS, and from the web. Ubuntu One offers 5GB of free storage space to everyone. Ubuntu One includes features for sharing files or folders online, streaming music to your smartphone, synchronizing installed applications across all your devices, and more. How to Use an Xbox 360 Controller On Your Windows PC Download the Official How-To Geek Trivia App for Windows 8 How to Banish Duplicate Photos with VisiPic

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  • Friday Fun: Shape Fold

    - by Asian Angel
    This week’s game comes with lots of puzzle solving, brain-teasing goodness to keep you busy. On each level you will need to rotate, twist, and/or move the hinged puzzle pieces into their proper shape. Do you have the patience and skill to solve all the puzzles or will you be forced to admit defeat? 7 Ways To Free Up Hard Disk Space On Windows HTG Explains: How System Restore Works in Windows HTG Explains: How Antivirus Software Works

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  • Isometric screen to 3D world coordinates efficiently

    - by Justin
    Been having a difficult time transforming 2D screen coordinates to 3D isometric space. This is the situation where I am working in 3D but I have an orthographic camera. Then my camera is positioned at (100, 200, 100), Where the xz plane is flat and y is up and down. I've been able to get a sort of working solution, but I feel like there must be a better way. Here's what I'm doing: With my camera at (0, 1, 0) I can translate my screen coordinates directly to 3D coordinates by doing: mouse2D.z = (( event.clientX / window.innerWidth ) * 2 - 1) * -(window.innerWidth /2); mouse2D.x = (( event.clientY / window.innerHeight) * 2 + 1) * -(window.innerHeight); mouse2D.y = 0; Everything okay so far. Now when I change my camera back to (100, 200, 100) my 3D space has been rotated 45 degrees around the y axis and then rotated about 54 degrees around a vector Q that runs along the xz plane at a 45 degree angle between the positive z axis and the negative x axis. So what I do to find the point is first rotate my point by 45 degrees using a matrix around the y axis. Now I'm close. So then I rotate my point around the vector Q. But my point is closer to the origin than it should be, since the Y value is not 0 anymore. What I want is that after the rotation my Y value is 0. So now I exchange my X and Z coordinates of my rotated vector with the X and Z coordinates of my non-rotated vector. So basically I have my old vector but it's y value is at an appropriate rotated amount. Now I use another matrix to rotate my point around the vector Q in the opposite direction, and I end up with the point where I clicked. Is there a better way? I feel like I must be missing something. Also my method isn't completely accurate. I feel like it's within 5-10 coordinates of where I click, maybe because of rounding from many calculations. Sorry for such a long question.

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  • Design Issues With Forms

    - by ultan o'broin
    Interesting article on UX Matters, well worth reading, especially the idea that global design research can take for a better user experience in all languages: Label Placement in Austrian Forms, with Some Lessons for English Forms What is perhaps underplayed here is the cultural influence of how people worked with forms in the past, and how a proper global user-centered design process needs to address this issue and move usability gains (in the enterprise space, productivity especially) in the right direction.

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  • Sprite sheet generator

    - by Andrea Tucci
    I need to generate a sprite sheet with squared sprite for a 2D game. How can I generate a sprite sheet where each frame has x = y? The only think I have to do is to "insert" some blank space between sprites (in case y were x in the original sprite). Is there any program that I can use to trasform "irregular" sprite sheets to "squared" sprite sheets? An example of non-squared sprite sheet: http://spriters-resource.com/gameboy_advance/khcom/sheet/1138

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  • Only a few places left for the SQL Social evening on 16th March

    - by simonsabin
    We've got over 50 people registered for the SQLSocial event on 16th March with Itzik Ben-Gan, Greg Low, Davide Mauri and Bill Vaughn I need to finalise numbers on early next week so if you want to come along please register asap, otherwise I can't promise that we'll have space for you. To register use he form on herehttp://sqlsocial.com/events.aspx. I look forward to hearing from you.

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  • Windows 8: Everything from design, build, and how to sell a Metro style app

    - by Thomas Mason
    For me, there are a lot of similarities between an application developed for Windows Phone and a Metro style app developed for Windows 8. A Windows Phone 7 application (rather than an XNA game) is built in .NET and XAML against a subset of the .NET framework and the application has a lifecycle which needs to be conscious of battery life and so is split out into foreground/background pieces. The application is sandboxed in terms of its interactions with the local device and is packaged with a manifest which describes those interactions. The app needs to be aware of network connectivity status and its work on the network is done asynchronously to preserve the user experience.The app is packaged and deployed to a Marketplace which the user browses to find the app, read reviews, perhaps purchase it and then install it and receive updates over time. Quite a lot of those statements are as true of a Windows 8 Metro style app as they are for a Windows Phone app and so a Windows Phone app developer already has a good head start when it comes to building Metro style apps for Windows 8. With that in mind, there is an event to help developers with a Windows Phone app in Marketplace to begin the process of looking at Windows 8 and whether you can get a quick win by bringing your Phone application onto Windows. The idea of the event was to provide a space where developers can get together over 2 days and take the time out to look at what it means to take their app from Windows Phone to Windows 8. Kicking off on Saturday 16th June at 10am, we are told they have plenty of power sockets, WiFi, whiteboards, drinks, pizza, games, prizes and some quiet space that you can work in. Including people on hand with Windows Phone and Windows 8 experience to help everything along the way. There will be an attendee-voted schedule of talks but we’ll keep these out of your way if you just want to get on and code. We’ll also provide information around submitting your app to the Windows Store If you have a Windows Phone app in Marketplace, now’s a great time to look at getting it onto Windows 8. Sign up. Bring your laptop. Bring your app. Bring Windows 8 and Visual Studio 11. And everyone will their best to help you get your app onto Windows 8. Location & Venue TBA but it will be in central London, accessible by major railway and underground transportation. Day 1 Saturday 16th June 10am – 9pm Day 2 Sunday 17th June 10am – 4pm

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  • What is causing my spacebar to randomly stop working?

    - by Chris Billington
    A couple of times a day, I'll be typing something and realise I can't type spaces. Usually the cursor will flicker instead when I press the spacebar, and I can type all other letters as far as I can tell. If I'm in a terminal the cursor turns from a solid square to an empty square until I release the spacebar. For some reason, restarting compiz with alt-F2 compiz fixes it, until it next occurs. I can still copy and paste spaces from sources that already have them, and I can still insert spaces with ctrl-shift-u, 20, enter. This has been happening for a while, since before I upgraded to maverick, but it feels like its beceoming more frequent. There really doesn't seem to be any kind of a pattern to it. I'm using 64 bit ubuntu 10.10 on a system76 panp7 laptop. Any ideas how I might troubleshoot? EDIT: using xev, normally a spacebar registers as: KeyPress event, serial 36, synthetic NO, window 0x5600001, root 0x101, subw 0x0, time 26488647, (88,403), root:(748,458), state 0x10, keycode 65 (keysym 0x20, space), same_screen YES, XLookupString gives 1 bytes: (20) " " XmbLookupString gives 1 bytes: (20) " " XFilterEvent returns: False KeyRelease event, serial 36, synthetic NO, window 0x5600001, root 0x101, subw 0x0, time 26488729, (88,403), root:(748,458), state 0x10, keycode 65 (keysym 0x20, space), same_screen YES, XLookupString gives 1 bytes: (20) " " XFilterEvent returns: False But when it's stopped behaving a press of the spacebar instead gives the three events: FocusOut event, serial 36, synthetic NO, window 0x5600001, mode NotifyGrab, detail NotifyAncestor FocusIn event, serial 36, synthetic NO, window 0x5600001, mode NotifyUngrab, detail NotifyAncestor KeymapNotify event, serial 36, synthetic NO, window 0x0, keys: 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 FURTHER EDIT: Ok, so I think I've solved the problem, and by that I mean I now know which package to file a bug against. I have a hot corner which initiates a window picker, and I've customised the window picking so that left click goes to a window, right click closes one and spacebar zooms in on one. When I go to this hot corner, compiz must take control of my spacebar, and clearly isn't giving it back when I leave the window picker. So I'll be filing a bug against compiz. reported:here

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  • Oracle VM Templates for EBS 12.1.3 for Exalogic Now Available

    - by Elke Phelps (Oracle Development)
    Oracle VM Templates for Oracle E-Business Suite 12.1.3 for x86 Exalogic Platform (64 bit) are now available on the Oracle Software Delivery Cloud.  The templates contain all the required elements to create an Oracle E-Business Suite R12 demonstration system on an Exalogic server. You can use these templates to quickly build an EBS 12.1.3 demonstration environment, bypassing the operating system and the software install (via the EBS Rapid Install).   The Oracle E-Business Suite Release 12.1.3 (64 bit) template for the Exalogic platform is a Oracle Virtual Server Guest template that contains a complete Oracle E-Business Suite Release 12.1.3 Database Tier and Application Tier Installation.  For additional details, please refer to the following My Oracle Support Note: Oracle E-Business Suite Release 12.1.3 Database Tier and Application Tier Template for Oracle Exalogic Platform (Note 1499132.1) The Oracle E-Business Suite system is installed on top of Oracle Linux Version 5 update 6. The templates have been optimized for performance, including OS kernel settings and E-Business Suite configuration settings tuned specifically for the Exalogic platform.  The configuration delivered with this template for a mid-tier running on Exalogic will support hundreds of concurrent users.  Please refer to Section 2: Performance Analysis in My Oracle Support Note 1499132.1 for additional details.   Additional Information The Oracle E-Business Suite VM templates for the Exalogic platform contain the following software versions: Operating System: Oracle Linux Version 5 Update 6 Oracle E-Business Suite 12.1.3 (Database Tier) Oracle E-Business Suite 12.1.3 (Application Tier) The following considerations were made when the Oracle E-Business Suite VM template for the Exalogic platform were designed: Templates use the hardware-virtualized architecture, supporting hardware with virtualization feature. Database Tier Template is configured to use the following configuration: 16 GB RAM 4 VCPUs 250 GB of Disk space for application installation Application Tier Template is configured to use the following configuration: 16 GB RAM 4 VCPUs 50 GB of Disk space for application installation References Oracle E-Business Suite Release 12.1.3 Database Tier and Application Tier Template for Oracle Exalogic Platform (Note 1499132.1) Related Articles Part 1: E-Business Suite 12.1.1 Templates for Oracle VM Now Available Part 2: Using Oracle VM with Oracle E-Business Suite Virtualization Kit Part 3: On Clouds and Virtualization in EBS Environments (OpenWorld 2009 Recap) Part 4: Deploying E-Business Suite on Amazon Web Services Elastic Compute Cloud Part 5: Live Migration of EBS Services Using Oracle VM Support Policies for Virtualization Technologies and Oracle E-Business Suite Virtualization and the E-Business Suite, Redux Virtualization and E-Business Suite

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  • Learning PostgreSql: Reading and Writing From .Net

    - by Alexander Kuznetsov
    In this post we shall do some setup tasks, save a few rows of data from a .Net client to PostgreSql, and read it back. Setting up We have set up a virtual machine running Red Hat Linux, installed PostgreSql 9.3 on it, and made sure there is enough disk space. 9.3 is a very recent version, released this September. Because PostgreSqlis not known for releasing before the full testing is complete, we did not have to wait for the next service pack or something like that. Smoke test On the client machine...(read more)

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  • EPM 11.1.2 - R&A DATABASE CONNECTIONS DISAPPEAR FROM THE "DATABASE CONNECTION MANAGER

    - by Powder
    When accessing the database connection panel through Reporting and Analysis all previously entered database connection do not appear. This is due to a bug in the Windows SMB2 protocol. To work around this bug you have to disable the protocol. On Windows 2008 the protocol is automatically enabled. This needs to be done on both the servers and the clients. Note that “server” is the server which hosts RAF repository service and RM1 folder, “client” – server which hosts replicated Repository service that accesses repository files via network i.e. \\<server_host>\RM1  In order to disable SMB 2.0 on the server side, follow these steps:  1. Run "regedit" on Windows Server 2008 based computer.  2. Expand and locate the sub tree as follows.  HKLM\System\CurrentControlSet\Services\LanmanServer\Parameters  3. Add a new REG_DWORD key with the name of "Smb2" (without quotation mark)  Value name: Smb2  Value type: REG_DWORD  0 = disabled  1 = enabled 4. Set the value to 0 to disable SMB 2.0, or set it to 1 to re-enable SMB 2.0.  5. Reboot the server.  To disable SMB 2.0 for Windows Vista or Windows Server 2008 systems that are the “client” systems run the following commands:  sc config lanmanworkstation depend= bowser/mrxsmb10/nsi  sc config mrxsmb20 start= disabled  Note there's an extra " " (space) after the "=" sign.  To enable back SMB 2.0 for Windows Vista or Windows Server 2008 systems that  are the “client” systems run the following commands: sc config lanmanworkstation depend= bowser/mrxsmb10/mrxsmb20/nsi  sc config mrxsmb20 start= auto  Again, note there's an extra " " (space) after the "=" sign. 

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  • Desktop Fun: Wolves Wallpaper Collection Series 2

    - by Asian Angel
    Early last year we shared a wonderful collection of wolves wallpapers with you and today we are back we more to increase the size of your ‘wolf pack’. Feel the call of the wild on your desktop with the second in our series of Wolves Wallpaper collections. 7 Ways To Free Up Hard Disk Space On Windows HTG Explains: How System Restore Works in Windows HTG Explains: How Antivirus Software Works

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  • Ubuntu 11.10 running in windows 7 (wubi) AND on a separate partition

    - by Pareen
    I am in a very strange situation and need some help: I installed Ubuntu 11.10 through Wubi a while back so that I can use it alongside Windows 7. I was running out of space on my disk when trying to install applications. Without understanding how Wubi worked, I partitioned my C drive (creating a new 90 GB partition) in Windows, booted from the Ubuntu 11.10 install/live disk, and used the "something else" option to create a ext4 (setting the mount point to root) and swap space partitions (/sda5 and /sda6). After the install, my computer no longer boots with the previous Wubi menu and is now using the Linux grub. The options I have are /sda2, which boots Windows 7; /sda1, which doesn't do anything and reloads the same menu, and the run Linux options. So I now have Ubuntu running on a separate partition, as well as the original Wubi install. I want to delete the seperate partition and go back to running Ubuntu on Wubi...if I remove the partition will I need the Windows 7 disk to restore the boot loader? I dont have the Windows 7 disk on me so what is the best way to clean this up so I get rid of the seperate partition? -------------------------------------------------UPDATE----------------------------------------------------- ============================================================================================================ thank you so much for your response. Actually, it would be fantastic if I could migrate my Wubi install into the new partition because I had downloaded the AOSP on the Wubi install (as well as other files) and would love to preserve them. If i can do that and work on the new partition with the old files than that would be great, and I can worry about wiping out the partition completely later on i.e. when I have the windows disk or something. Can you tell me how to do this migration?? So when I select the /sda2, it loads up my Windows. If i click on the Linux, it loads up the newly install Linux (my files that were on the Wubi install aren't there) fine. If I click on the /sda1 (SYSTEM_DRIVE... this is what the Wubi was using to boot the menu that let me select Windows 7 or Ubuntu)... it fails and just reloads the original menu. Here is the link to my boot info script http://pastebin.com/dMrY0NL3

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  • Laser Beam End Points Problems (XNA)

    - by user36159
    I am building a game in XNA that features colored laser beams in 3D space. The beams are defined as: Segment start position Segment end position Line width For rendering, I am using 3 quads: Start point billboard End point billboard Middle section quad whose forward vector is the slope of the line and whose normal points to the camera The problem is that using additive blending, the end points and middle section overlap, which looks quite jarring. However, I need the endpoints in case the laser is pointing towards the camera! See the blue laser in particular:

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  • Inverted schedctl usage in the JVM

    - by Dave
    The schedctl facility in Solaris allows a thread to request that the kernel defer involuntary preemption for a brief period. The mechanism is strictly advisory - the kernel can opt to ignore the request. Schedctl is typically used to bracket lock critical sections. That, in turn, can avoid convoying -- threads piling up on a critical section behind a preempted lock-holder -- and other lock-related performance pathologies. If you're interested see the man pages for schedctl_start() and schedctl_stop() and the schedctl.h include file. The implementation is very efficient. schedctl_start(), which asks that preemption be deferred, simply stores into a thread-specific structure -- the schedctl block -- that the kernel maps into user-space. Similarly, schedctl_stop() clears the flag set by schedctl_stop() and then checks a "preemption pending" flag in the block. Normally, this will be false, but if set schedctl_stop() will yield to politely grant the CPU to other threads. Note that you can't abuse this facility for long-term preemption avoidance as the deferral is brief. If your thread exceeds the grace period the kernel will preempt it and transiently degrade its effective scheduling priority. Further reading : US05937187 and various papers by Andy Tucker. We'll now switch topics to the implementation of the "synchronized" locking construct in the HotSpot JVM. If a lock is contended then on multiprocessor systems we'll spin briefly to try to avoid context switching. Context switching is wasted work and inflicts various cache and TLB penalties on the threads involved. If context switching were "free" then we'd never spin to avoid switching, but that's not the case. We use an adaptive spin-then-park strategy. One potentially undesirable outcome is that we can be preempted while spinning. When our spinning thread is finally rescheduled the lock may or may not be available. If not, we'll spin and then potentially park (block) again, thus suffering a 2nd context switch. Recall that the reason we spin is to avoid context switching. To avoid this scenario I've found it useful to enable schedctl to request deferral while spinning. But while spinning I've arranged for the code to periodically check or poll the "preemption pending" flag. If that's found set we simply abandon our spinning attempt and park immediately. This avoids the double context-switch scenario above. One annoyance is that the schedctl blocks for the threads in a given process are tightly packed on special pages mapped from kernel space into user-land. As such, writes to the schedctl blocks can cause false sharing on other adjacent blocks. Hopefully the kernel folks will make changes to avoid this by padding and aligning the blocks to ensure that one cache line underlies at most one schedctl block at any one time.

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