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Serious bug in NVidia drivers (vblank)
In our company we are working on a simulation project in which we have several threads competing for the CPU. The main thread draws with OpenGL the scene, and other threads do I/O and some processing.
The bug we have found is that the main thread uses the 100% of the CPU even if we synchronize with vertical retrace. This is a very serious bug for our sort of projects, because the other threads need the idle time of the main thread to do their work :'( As a result, our application is running much slower than it could run if the driver waited until the vertical retrace.
If it will late too much to fix this bug, is there any workaround that we can do in the meanwhile, please?
This isn't a bug with the drivers, it's a side effect of the Linux kernel timer resolution. The kernel scheduler (at least, this is my understanding of it) runs once every 1/HZ seconds (HZ is 100 on Intel machines, and 1024 on certain others).
This means that there is a latency of 1/HZ seconds, or 10ms, possible if any thread (or process) gives up control.
This also means that the vertical retrace can't be synced to by waiting for an interrupt; the userspace code that runs in response to that interrupt might be very, very late.
So instead, the drivers busy-wait on the vertical retrace signal. When a retrace is in progress, they return (and glXSwapBuffers finishes).
The only way to change this is to change the kernel timer resolution. Or, change your threading package to be a preemptive one (AKA pthreads) rather than a cooperative one. There's no reason a high CPU utilization in one thread would stop others from running, especially if they're only doing I/O, unless you're using a userspace threading package that can only do cooperative multitasking.
polling also doesn't sync well
In fact we are using pthreads, and in a preemtive configuration. Of course while the first thread is doing the polling, it's possible that other threads take the control of the CPU, but some comments on this:
If the draw thread is heavily using the CPU and the other too, the other will have ideally only half of the CPU time it could have (while SwapBuffers). So our app could be faster than it is.
Moreover, while the draw thread is polling for the retrace, it's possible that the sheduler gives the CPU to the second thread (or even another process), and when the draw thread recovers the CPU, it could be too late.
So how can it guarantee to be in time even doing "busy wait"? In fact, the driver in our machine is not syncing the swap buffers with vertical retrace correctly (even though it is eating all CPU available).
There is a possibility of changing the HZ constant of the kernel, or use a 2.5 kernel for our app. But I think it will not solve any of the problems we have.
You just made me feel so un1337...
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Apple EarPods with Remote and Mic
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Apple In-Ear Headphones with Remote and Mic
" Prelude Apple's stock earbuds that have been shipped with every iPod since its inception are quite possibly the most prolific and widely distributed tech accessory of all time. It's hard to go anywhere without seeing a pair of these things dangling from someone's ears. Casual listeners are bound to be satisfied by the decent performance of the earbuds but what about audiophiles? It's..." --TheGame21x
Future Sonics Ear Monitors with 13mm MG6pro Dynamic Drivers
" Hi everyone, here's my first (brief) review of the MG6 Pro In-ears by Future Sonics.. First, i'd like to note that Mr. Marty Garcia (CEO FutureSonics) is a complete gentleman, he took time to answer ALL my questions on phone and emails too! That's rare and heart warming.. - a far cry from Sensaphonics where i encountered a completely rude rep, and Ultimate ears that won't answer or..." --SammyDplus
Future Sonics mg6pro
" Synopsis: The Future Sonics MG6Pro Ear Monitor is an excellent sounding custom earphone tuned for a supremely natural sound. The overall sound is very smooth, extended in bass and treble, and very well balanced by the clear midrange. The excellent reproduction of vocal and instrumental timbre, combined with superior soundstage and sense of stereo imagining are also standouts. Using a single..." --Kunlun
Future Sonics mg5pro 10mm Ear Monitors
" Synopsis: The Future Sonics MG5pro is a professional stage monitor for audiophiles. It offers a different tuning than its brother, the fully stage-oriented MG6pro, by offering a brighter, more overall tonally balanced tuning. The MG5pro lifts the vocal ranges and matches this with an accurate, well extended treble. The bass is very well controlled and yet has one of the most real..." --Kunlun
Apple iPod Earphones Headphones for iPod Nano, Touch & Classic
"I'm not sure if this is the same model I got with my iPhone 4s or not. There have been tons of different models of these buds released for different i-devices. The ones that I received with my 4s are (In my opinion ) absolutely worth at least 30-45 $ in my opinion. No they don't sound like my SENN HD 600 by any means at all, but for an earbud they are exceptional. The..." --GoldenGuy66
Ipod Earbuds Headphones for Nano
" 6.50 on ebay brand new 9.50 for the pair with a remote for that price. you gotta love it lol " --jockhater2
Apple In-Ear Headphones (White)
" I don't know whether it's a conspiracy or a joke, but Apple's talk of these being good quality just makes them seem like hilarious liars who could sell ice to eskimos. If their intent is to drive aftermarket sales, then they've managed it. As far as I can tell these things literally don't play bass. It's just not there. The midrange is ok, and if you're tired, they're ok for watching movies..." --BBBS
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*german accent* Hallo everyone!! I would like to say danke for the birthday wishes! It made me very happy! I had a wünderbar day. Kevin made a surprise dinner for us in the park und we took a nice ride on a boat as Kevin rowed. Heehee. He's so romantic.
I'm sorry for being away too long und not answering your questions. I was doing some activities und working on a composition for the school. I cannot say what it is, because I do not want to ruin the surprise. Teehee!!
Once again, danke so much for the birthday wishes. Bye-Bye for now!
-Adele Hertz


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Originally written on Patriots Life | Last updated 12/6/12
A terrific sign for Patriots fans, as there's the slightest of chances that the Patriots could get their best pass rusher and best offensive lineman back for Monday's game.WEEI:After being spotted at Patriots practice for a second straight day, and barring any late setbacks, Logan Mankins and Chandler Jones will be ready to play Monday night when the Patriots host the Texans at Gillette Stadium, according to a report by CSNNE's Mike Giardi. Giardi tweeted Thursday, being told Logan Mankins will play Monday, barring a setback. Pats plan all along. He'll join Chandler Jones. As we've seen countless times this year, practicing is no guarantee of playing. Aaron Hernandez practiced entire weeks a couple of times and didn't play. However, some practice is better than no practice. There's at least the chance that these two - who have missed multiple games already - might just be rested up enough to fainlly be able to take the field.I touched on the importance of Logan Mankins yesterday but...
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« July 24 July 26 » Sunday, July 25, 2010
Man, 23, killed in police stop
July 25, 2010 in City on Page B2 SILVERDALE, Wash. – The family of a man killed in Silverdale on Friday night said he was in the process of "turning his life around." Matthew James Netter, 23, of …
Farm work seminars draw little interest
July 25, 2010 in City on Page B2 Critics of U.S. immigration policy maintain that undocumented workers take jobs from U.S. citizens and legal residents, but those who make a living in agriculture say this is not so. …
Mager faces 4 GOP challengers
July 25, 2010 in City on Page B3 As the only Democrat and the only woman, Bonnie Mager stands out among the candidates for her Spokane County commissioner position. Standing apart could help her survive next month's primary … 22
Spokane County commissioner candidates, issues
July 25, 2010 in City on Page B3 Candidate Q&A 3
Fishing for predators a payoff in retirement
July 25, 2010 in City on Page B7 WENATCHEE – For 30 years, Bruce Arndt put in long, hot hours inside the Alcoa aluminum smelting plant near Malaga, Wash. Today, his post-retirement routine includes an alarm clock sounding …
Bank robber's arrest left wife stunned, struggling
July 25, 2010 in City on Page B7 PORT TOWNSEND, Wash. – For 25 years, you've known this man, your husband. You know Michael Fenter so well, it's almost as if you and he were one. This farm …
Naked protest curtailed
July 25, 2010 in City on Page B7 A group of 15 bicyclists in various stages of nakedness rode Friday night from Belltown through downtown Seattle and up to Capitol Hill, where they were stopped by Seattle police, …
Waste, fraud not confined to security
July 25, 2010 in Opinion on Page B8 Congratulations are due to the Washington Post. "Top Secret America," its in-depth, multipart, two-year investigation into the vast network of government security agencies and private contractors, is an eye-opener – … 1
Editorial: Government buck-passing is no relief to taxpayers
July 25, 2010 in Opinion on Page B8 Gov. Chris Gregoire's traveling austerity show comes to town on Thursday. The series of public forums, where the state's fiscal woes are to be laid out and the public's input … 1
Governor races merit notice
July 25, 2010 in Opinion on Page B8 In this high-stakes election of 2010, much attention naturally focuses on Republican efforts to come back in Congress and the Democrats' drive to retain their large majorities in the House …
Rule of law in peril
July 25, 2010 in Letters, Opinion on Page B9 What laws do the rest of us get to break? The USA is a country of laws and legal immigration.
Union help unneeded
July 25, 2010 in Letters, Opinion on Page B9 Employers everywhere are re-evaluating benefit packages in these times of financial uneasiness.
Safety needs regional plan
July 25, 2010 in Opinion on Page B9 On July 14 a young man was gunned down in front of my home and died on the neighbor's lawn. He lay there, in a heap, for hours while police … 1
Different kind of politician
July 25, 2010 in Letters, Opinion on Page B9 One of the most common complaints I hear about political candidates is, "They're all the same. It doesn't matter who I vote for."
Warming up to Obama
July 25, 2010 in Letters, Opinion on Page B9 Last year I qualified to get my home weatherized. It was part of the stimulus package to make older homes more energy-efficient. They insulated pipes and installed an energy-efficient hot … 4
No leniency for robbers
July 25, 2010 in Letters, Opinion on Page B9 Spokane is not the safe city I grew up in. Suspects arrested by police for felony crimes are being released from jail because Prosecuting Attorney Steve Tucker won't charge them …
Care tied to doctors' pay
July 25, 2010 in Letters, Opinion on Page B9 This is for all people on Medicare. Do you know Congress wants to cut doctors' fees by 2l percent?
Respect goes both ways
July 25, 2010 in Letters, Opinion on Page B9 I first met John Ahern when I was serving as a representative for the city of Medical Lake on a DSHS committee looking into standards for housing sex offenders. John … 2
Reciprocity is the answer
July 25, 2010 in Letters, Opinion on Page B9 To ensure fairness in immigration laws, how about using the principle of reciprocity? For example, the same legal process and penalties that Mexico would apply to a U.S. citizen who …
Hard time made easier
July 25, 2010 in Letters, Opinion on Page B9 I was happy to see the editorial on Tuesday "Hospice care fills void at limits of medicine." I know what a blessing the Hospice House has been for patients and … 1
Democrats prevail at spending
July 25, 2010 in Letters, Opinion on Page B9 In response to Froma Harrop's column from Saturday, July 17, "Return to crazy years can't be answer," these are the crazy years when it comes to government spending and regulation.
Gold seekers take a shine to Oregon
July 25, 2010 in City on Page B10 GOLD HILL, Ore. – After California shut down gold mining with suction dredges, Dave McCracken loaded his gear and drove over the Siskiyou Mountains to Southern Oregon, where he is …
In brief: Aggressive panhandler shot outside McDonald's
July 25, 2010 in City on Page B10 EVERETT – A 61-year-old man was jailed Saturday afternoon after he allegedly shot a man who aggressively begged for money outside a McDonald's in downtown Everett, according to Everett police. … 4
Indians bust loose with 11 runs to keep East lead
July 25, 2010 in Sports on Page C1 With Monday marking the halfway point in the Northwest League season, as well as the first opportunity to earn a playoff berth, every game of the four-game set with Tri-City …


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Videos >> Browse Videos
Browse Videos
Deadly car crash videoSpeed thrills but kills. The car crashed at 220km/h and the driver didn't survive!85 Views0 Comments
Kids on a rampageThese kids steal a SUV and go on a rampage.35 Views1 Comment
Armored bulldozer goes on rampageCity council closed his business and he was not too happy.44 Views4 Comments
Idiots Rob the Wrong Store...I mean come on...how stupid do you have to be?Submitted by AZmeangreen | almost 8 years ago89 Views5 Comments
C.S.I.Might be offensive...Yet funny !!Submitted by Peytonsdad05 | almost 8 years ago48 Views3 Comments
Stupid guy jumps from moving vehicleThis is why breeding should be controlled.Submitted by AZmeangreen | almost 8 years ago71 Views2 Comments
London police arrestPostman is assaulted by cops for refusing to move his van. Policeman at back punches him in groin, big crowd, possible injury (This is directly from the original taper of this video and his own comments)56 Views3 Comments
Gloucester Police Chief confronted by reporterPolice Chief had assaulted reporter when he was 15.100 Views3 Comments
Man tries to take a Court officer's weaponNot sure what was going through this guy's head, maybe a court case didn't go in his favor and he had a death wish3063 Views114 Comments
Celebrity 911 callsCelebrities sometimes have to call 911 too, and this a collection of their calls. Included here are Joaquin Phoenix (when his brother River OD'ed), Demi Moore, Ashley Judd, Drew Barrymore, Janet Jackson, Tonya Harding, and William Shatner.85 Views0 Comments
A Very Good Day to a Very Bad DayThis sucks, I have had this happen to me, but luckily not to this extentSubmitted by LSpiveyA24 | almost 8 years ago112 Views8 Comments
Officer Involved ShootingThis will make the hair on the back of your neck stand upSubmitted by LSpiveyA24 | almost 8 years ago197 Views14 Comments


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This velvet headboard attaches to your bed frame simply and easily, for a serious touch of class and a softer place to lean when sitting in bed than that unforgiving wall. The headboard is constructed with soft cotton velvet with a tufted vintage hand, and an adjustable to accommodate either a full or queen-sized bed frame. UO Exclusive.
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6 Gorgeous Swimsuits for Your Next Island Getaway view
Pool Party Style view
How to Pack for a Super-Stylish Memorial Day Weekend view
Wow! Day one of New York Fashion Week was a huge success! I snapped photos of all...
Wow! Day one of New York Fashion Week was a huge success! I snapped photos of all the buzz-worthy fashionistas throughout the tents and hung out with some of my favorite designers including Alexander Wang pictured here. I ended my night dashing from event to event to give you the scoop on the biggest shopping event of the year—Fashion's Night Out, present by Vogue, NYC & Co., and the CFDA.
By Stylist Ludget Delcy
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