- Cache Coherency: Since vSMP technology does not allow both the Companion core and the main cores to be enabled at the same time, there are no penalties involved in synchronizing caches between cores running at different frequencies. The Companion and main cores share the same L2 cache, and the cache is programmed to return data in the same number of nanoseconds for both Companion and main cores (essentially it takes more “main core cycles” versus fewer “Companion core cycles” because the main cores run at higher frequency).
- OS Efficiency: The Android OS assumes that all available CPU cores are identical with similar performance capability and schedules workloads to these cores accordingly. When multiple CPU cores are each run at different asynchronous frequencies, it results in the cores having differing performance capabilities. This could lead to OS scheduling inefficiencies. In contrast, vSMP technology always maintains all active cores at a similar synchronous operating frequency for optimized OS scheduling. Even when vSMP switches from the Companion core to one or more of the main CPU cores, the CPU management logic ensures a seamless transition that is not perceptible to end users and does not result in any OS scheduling penalties.
- Power Optimized: Each core in an asynchronous clocking based CPU architecture is typically on a different power plane (aka voltage rail or voltage plane) to adjust the voltage of each core based on operating frequency. This could result in increased signal and powerline noise across the voltage planes and negatively impact performance. Since each voltage plane may require its own set of voltage regulators, these architectures may not be easily scalable as the number of CPU cores is increased. The additional voltage regulators increase BOM (Bill of Materials) cost and power consumption. If the same voltage rail is used for all cores, then each core will run at the voltage required by the fastest core, thus losing the advantage of the “voltage squared” effect for power reduction.
Wednesday, September 28, 2011
NVIDIA reveals a phantom fifth ARM Cortex-A9 processor core in Kal-El
Monday, September 26, 2011
Comparison between HEVC (H.265) and H.264
- 2-D non-separable adaptive interpolation filter (AIF)
- Separable adaptive interpolation filter
- Directional adaptive interpolation filter
- "Super macroblock" structure up to 64x64 with additional transforms
- Large transform block sizes (up to 32x32)
- Adaptive prediction error coding (APEC) in spatial and frequency domain
- Adaptive quantization matrix selection (AQMS)
- Competition-based scheme for motion vector selection and coding
- Mode-dependent KLT for intra coding
- Tree-structured prediction and residual difference block segmentation
- High-accuracy motion compensation interpolation (8 taps)
Wednesday, September 14, 2011
Nvidia quad-core chip powers Windows 8 demo tablet
Saturday, September 10, 2011
H.265 Motion Estimation on FPGA
Thursday, September 8, 2011
Vanguard Software Solutions Demonstrates H.265/HEVC CODEC
Sep 8, 2011 12:17:00 AM
Copyright Business WireVSS is well positioned to be a leading supplier of HEVC CODEC on multiple platforms. Having many years of CODEC experience and being the first to demonstrate H.264 real-time CODEC in 2004, VSS will be first to show a commercial version of HEVC software CODEC. Following PC software HEVC CODEC, VSS will be introducing commercial implementations on hardware platforms.
An Excellent Video Presentation: The Language of Concurrency
Saturday, September 3, 2011
How Qualcomm’s Snapdragon ARM chips are unique
- By Ryan Whitwam on August 26, 2011 at 9:00 am
There is a reason that so many mobile devices run on Qualcomm’s Snapdragon system-on-a-chip (SoC). Qualcomm is one of the largest designers of mobile ARM chips in the world, but it’s not just the scale that has made Qualcomm into a mobile powerhouse. The design and features of the Snapdragon SoC have proven to be a hit with users and device makers alike.
This esoteric bit of silicon might seem inconsequential, but it has a huge impact on the design and capabilities of a phone or tablet. Qualcomm has long prided itself on going its own way, and that’s evident in the design of the Snapdragon line of parts. Whereas chip designers like Samsung and Texas Instruments (TI) license the architecture for ARM’s Cortex cores, Qualcomm designed their own ARM-compatible cores.
In current generation SoCs, Qualcomm uses the Scorpion core instead of Cortex-A8. They license the ARM instruction set, so the chips remain compatible at the user level, but running the enhanced Scorpion core means more bang-for-the-buck when actually using a phone.
When it comes to that slab of glass and plastic that lives in pockets, it needs to be slim and well-designed. Qualcomm’s Snapdragon makes that easier from the perspective of the OEM. All SoCs integrate several system components into one package, but Qualcomm has taken this to the logical extreme. All generations of Snapdragon SoC have the processor, GPU, GPS, and most importantly, the GSM/CDMA cellular modem all in one package. This saves space and power in the phone. Designing a svelte, attractive device becomes easier when more components are in one piece of silicon. Similarly, the supply chain is simplified for the OEM if they do not need to source parts for as many individual components.
As Qualcomm moves forward, they aren’t done innovating. The new dual-core Snapdragons are beginning to make their way onto the market in devices like the HTC Sensation and Evo 3D. Unlike competing the dual-core chips from Nvidia and TI, the Snapdragon with its custom Scorpion cores is capable of asymmetric use. This essentially means the cores can be clocked independently and have different power draws. Users will see better power management from these chips, even in a dual-core world.
Since Qualcomm’s dual-core SoCs are still using Scorpion, they are reaching the limits of the architecture. Scorpion was designed to emulate last year’s ARM Cortex-A8. Chips like the Nvidia Tegra 2 and Samsung Exynos license Cortex-A9, which is a generation newer.
The big change is set to come in the fourth generation Snapdragons with the introduction of the Krait core. Krait is expected to be paired with a new generation of Adreno mobile graphics and use a much more advanced manufacturing process. The upshot for users being that Qualcomm’s new chips are likely going to be blisteringly fast. According to Qualcomm, the power consumption of these faster SoCs will be even better than Scorpion-based units. That’s a big deal for users that need an all-day device.
The new dual and quad-core Snapdragons running Krait cores are expected to begin showing up late in 2011, and into 2012. Bringing together these new features with the innovative SoC design seen in recent years, Qualcomm’s Snapdragon chips could be headed for continued dominance in mobile devices.
Followers
Blog Archive
-
▼
2011
(186)
-
▼
September
(7)
- NVIDIA reveals a phantom fifth ARM Cortex-A9 proce...
- Comparison between HEVC (H.265) and H.264
- Nvidia quad-core chip powers Windows 8 demo tablet
- H.265 Motion Estimation on FPGA
- Vanguard Software Solutions Demonstrates H.265/HEV...
- An Excellent Video Presentation: The Language of C...
- How Qualcomm’s Snapdragon ARM chips are unique
-
▼
September
(7)