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Heechul Yun
Attended University of Illinois at Urbana-Champaign
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Heechul Yun

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These days, there are not many differences between embedded systems and super computers. I'm excited to study how we can tame these highly parallel machines to be used safely in critical embedded systems.
CES 2015 has started, and the first company to present their innovations is Nvidia. Last year their introduced Tegra K1, the first mobile processor with a desktop GPU with support for OpenGL. They've now raised the bar with Tegra X1, an octa-core 64-bit ARM processor with a 256-core Maxwell GPU ...
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Clear explanation about what happened on the NYSE fiasco (http://buzz.money.cnn.com/2012/08/01/trading-glitch/?iid=H_MKT_News)
As everyone knows, I adore post mortems; there's so much to learn. As David Wilson points out on his python sweetness blog, this is one of the greatest bug descriptions of all time, and even though it's contained in an offic...
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Very nice summary of the state of art in debugging
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Now the real game will begin.
Finally, the day has come. The first upstream patch for 64bit ARM architecture hit the LKML [1]. And as always, LWN summerise the matter nicely [2]. It is done by, of course, ARM forks---namely Catali...
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"Intel in particular has a 20-year head start over ARM, resulting in a maturity, sophistication and veneration that will be hard to displace by a 12-year-old."  Long history often means legacies that are vulnerable to  disruption from young but innovative technology. But I do agree Intel is very very strong technology company tough to beat.
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What I like the most is WFE/SEV (a kind of suspend/wakeup) part of the code that could save energy instead of actually "spinning" the loop.
Spinlock is a synchronization mechanism frequently used in kernel developement to provide low cost synchronization between multiple cores. Its implementation heavily depends on hardware architecture. ...
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Heechul Yun

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What a fun introduction to a piece of software ! 
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"Vehicle tests confirmed that one particular dead task would result in loss of throttle control, and that the driver might have to fully remove their foot from the brake during an unintended acceleration event before being able to end the unwanted acceleration."

This is interesting. The article suggests that both hardware (Non ECC capable RAM) and software issues (stack overflow, ...)  can cause the situation resulting in an unintended acceleration. But the article lacks many details. I wish I can access more detailed analysis and the source code. 
 
If you haven't seen this report about Toyota's firmware design and consequences, please read it, it's very worth it.

Every once in a while I think someone needs to start a consulting company made up of grumpy kernel maintainers who have been doing code review for years, and let them loose on your internal projects to savage them and find the problems.  I'm sure engineers would hate to see us show up, but man, that would be fun and hopefully clean up the state of closed software (we all know it's this bad, and worse, but no one likes to admit it...)
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Great talk and I learned a lot from it. One thing I noticed is their heavy use of Linux kernel--- in particular cgroup and KVM. Cgroup is a key component to provide resource isolation among VMs while KVM enables VMs.
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So I can't run any custom kernel module on Google compute engine? It's bad. "Google Compute Engine kernels do not allow any modification or customization code to run at the kernel level."  Is amazon the same?
Machine Name, Description, Virtual Cores, Memory (MB), GCEUs, Additional Ephemeral Disk Size (GB), Max Number Of Persistent Disks (PDs), Max Total PD size (GB). n1-standard-1, Standard 1 CPU machine t...
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"Microsoft just eliminated any reason to buy a Windows Phone device today—echoing a distant-but-famous phenomenon known as the Osborne effect". So true.
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Have him in circles
73 people
PoLiang Wu (吳柏良)'s profile photo
Karsten Matthijs Hartog (χάος)'s profile photo
Sungpack Hong's profile photo
Wooil Kim's profile photo
Eunsoo Seo's profile photo
Minhee Cho's profile photo
Chi-Yao Hong (洪啟堯)'s profile photo
Moonyoung Chung's profile photo
Changyeon Jo's profile photo
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  • University of Illinois at Urbana-Champaign
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