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I have created a virtual machine using the VMWare software and getting an error while starting the Virtual Machine. It says "VT-x is not available:
00:00:03.916 NAT: zone(nm:mbuf_cluster, used:0)
00:00:03.916 NAT: zone(nm:mbuf_packet, used:0)
00:00:03.916 NAT: zone(nm:mbuf_jumbo_pagesize, used:0)
00:00:03.916 NAT: zone(nm:mbuf_jumbo_9k, used:0)
00:00:03.916 NAT: zone(nm:mbuf_jumbo_16k, used:0)
00:00:03.930 VMSetError: D:\tinderbox\win-4.0\src\VBox\VMM\VMMR3\VM.cpp(350) VMR3Create; rc=VERR_VMX_NO_VMX
00:00:03.930 VMSetError: Unknown error creating VM
00:00:03.931 ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={515e8e8d-f932-4d8e-9f32-79a52aead882} aComponent={Console} aText={VT-x is not available. (VERR_VMX_NO_VMX).
00:00:03.931 Unknown error creating VM (VERR_VMX_NO_VMX)}, preserve=false
00:00:03.944 Power up failed (vrc=VERR_VMX_NO_VMX, rc=E_FAIL (0X80004005))
Any idea why I am getting this error?
You might try reducing your base memory under settings to around 3175MB and reduce your cores to 1. That should work given that your BIOS is set for virtualization. Use the f12 key, security, virtualization to make sure that it is enabled. If it doesn't say VT-x that is ok, it should say VT-d or the like.
VT-x can normally be disabled/enabled in your BIOS.
When your PC is just starting up you should press DEL (or something) to get to the BIOS settings. There you'll find an option to enable VT-technology (or something).
Are you sure your processor supports Intel Virtualization (VT-x) or AMD Virtualization (AMD-V)?
Here you can find Hardware-Assisted Virtualization Detection Tool ( http://www.microsoft.com/downloads/en/details.aspx?FamilyID=0ee2a17f-8538-4619-8d1c-05d27e11adb2&displaylang=en) which will tell you if your hardware supports VT-x.
Alternatively you can find your processor here: http://ark.intel.com/Default.aspx. All AMD processors since 2006 supports Virtualization.
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I’ve been playing about with some of the Graphcore examples, specifically the TensorFlow CNN examples. I’ve been training ResNet with various command line options quite a few times successfully and now whatever command line I use I get the following error:
LLVM ERROR: IO failure on output stream: No space left on device
Why has the IPU run out of memory? Did a previous program exit unsuccessfully and leave the IPUs in a polluted state? A reboot helps for a while and then I run into the error again.
“Device” in this context actually refers to the host storage device rather than to the IPU device. This error is telling you that the disk being used for compilation is full. You can have a look at disk usage on an Ubuntu based host with the du or df commands. If any of the disks/filesystems are at or close to 100% full then you should delete some files to make space for compilation. The reason you are seeing reboots helping for a while is likely because the /tmp directory is being cleared; it will then fill up over time as you use the system. To mitigate against this it is advisable to have a large scratch file system on the machine you’re using to compile programs for the IPU.
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In the past few days I found how important is RTOS layer on the top of the embedded hardware.
My question is :
Is there any bifurcation between device driver (written in C directly burned over the microcontroller)
And the Linux Device driver ?
This question is a little broad, but an answer, a little broad itself, can be given.
The broadness comes from the fact that "embedded hardware" is not a precise term. That hardware ranges from 4 bit microcontrollers, or 8 pins ones, up to big CPUs which have many points in common with typical processors used tipically on linux machines (desktop and servers). Linux itself can be tailored up to the point it does not resemble a normal operating system anymore.
Anyway, a few things, generally acceptable, can be the following. Linux is not, in its "plain" version, a real time operating system - with the term RTOS instead, the "real time" part is implied. So, this can be one bifurcation. But the most important thing, I think, is that embedded firmware tries to address the hardware and the task to be done without anything else added. Linux O.S. instead is general purpose - it means that it offers a lot of services and functionalities that, in many cases, are not needed and only give more cost, less performances, more complication.
Often, in a small or medium embedded system, there is not even a "driver": the hardware and the application talk directly to each other. Of course, when the hardware is (more or less) standard (like a USB port, a ethernet controller, a serial port), the programming framework can provide ready-to-use software that sometimes is called "driver" - but very often it is not a driver, but simply a library with a set of functions to initialize the device, and exchange data. The application uses those library routines to directly manage the device. The O.S. layer is not present or, if the programmer wants to use an RTOS, he must check that there are no problems.
A Linux driver is not targeted to the application, but to the kernel. And the application seldom talks to the driver - it uses instead a uniform language (tipically "file system idiom") to talk to the kernel, which in turns calls the driver on behalf of the application.
A simple example I know very well is a serial port. Under Linux you open a file (may be /dev/ttyS0), use some IOCTL and alike to set it up, and then start to read and write to the file. You don't even care that there is a driver in the middle, and the driver was written without knowledge of the application - the driver only interacts with the kernel.
In many embedded cases instead, you set up the serial port writing directly to the hardware registers; you then write two interrupt routines which read and write to the serial port, getting and putting data from/into ram buffers. The application reads and writes data directly to those buffers. Special events (or not so special ones) can be signaled directly from the interrupt handlers to the application. Sometimes I implement the serial protocol (checksum, packets, sequences) directly in the interrupt routine. It is faster, and simpler, and uses less resources. But clearly this piece of software is no more a "driver" in the common sense.
Hope this answer explains at least a part of the whole picture, which is very large.
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Recently I am thinking to upgrade my current development laptop in newer machine. I'm all the while working under Linux/Windows dual boot and doing development work on both.
My current development platform including Java (Eclipse), Ruby/RoR (Gvim/Atom), Blender (learning), Erlang, ANSI C (VS/gcc), Android Studio for Android development, VirtualBox running Windows for Microsoft Office suite, C# development and MSSQL development. Sometimes need to debug as well under Virtualbox Windows by running Eclipse. Natively on Linux using MySQL/Postgresql for development and testing. I'm interested in exploring 3D and game programming as well.
Occasionally I do play some 3D games on Windows such as Modern Warfare 4, BF4 etc.
Now for the new year, thinking to upgrade to Macbook Pro but I'm undecided on to look at dualcore or should I stick to quadcore? Is there any benefit if I'm using quadcore for development purposes?
Googled and found the link below but it is done in year 2007.
http://blog.codinghorror.com/choosing-dual-or-quad-core/
http://blog.codinghorror.com/quad-core-desktops-and-diminishing-returns/
Understanding that utilizing multiple cores is mostly software or OS responsibility and this is easier to update to utilize those extra fire power.
So is it still trivial for development machine to have quadcore CPU as of 2015/2016? I've already targeted I'd take 16GB of RAM but not on CPU choice.
If you are looking for an upgrade I would recommend you to first look for a laptop that comes with a SSD harddisk because disk I/O is the typical performance bottleneck.
As for whether you should go for dual or quad cores... I personally think it doesn't really matter because not every piece of software is written to fully utilizes all CPU cores. It really depends on how the software is implemented. For instance if it is a multi-threaded or multi-process program then you will benefit heavily otherwise you probably won't see much of a difference. But the speed of your CPU core will definitely make a difference thou.
I see so you are also into games programming and some serious FPS gaming like BF4, then you will definitely need a powerful quad chipset and also an excellence graphics card. Otherwise if it is just for pure web/server development (not games), a good dual core should do it.
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http://www.sony.co.uk/product/vn-duo/svd1121z9e
I'm about to but the above laptop as a desktop replacement, but I want to know if it's a good enough processor to run VM's via hyper-v using windwos8.
not sure what Turbo Boost up to 3 GHz means,
Any input greatly received
It's a weird choice for desktop replacement, since it's not designed to be.
The first thing you want to know here, it's a U-series CPU, which means it uses considerably lower power. And that comes at a cost, the lower base CPU frequency. Yes, it can run up to 3.0 GHz, but again, better performance costs energy.
As it gives you a 6.5 hours battery life, the actual battery life when you Turbo Boost to 3.0 GHz will be considerably lower.
And for your another question, what is Turbo Boost? Turbo Boost is a technology to boost your CPU's performance when it's needed. Much like a smart power control that gives your CPU a push when it's needed.
Back to virtualization. It have two core, and I recommend using at least two cores for a virtual machine, so that leaves no spare core for your system, and that's a pretty bad idea. Also, 8 GB of memory may not be enough for a more memory-demand virtual machine.
For a desktop replacement, I will recommend a quad-core laptop, especially if you need to run a more performance-demand virtual machine.
Almost forgot one big thing, the screen size, 11" is really small, despite the high-resolution, your eyes might sour over time. I enjoyed programming on my much less powerful 21" desktop than my 15" laptop for the bigger screen. Unless you're going to pair it with an external display, I will suggest you consider AT LEAST a 13" model.
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I know the standard answer is No. However hear out the reasons for wanting it, and then we'll go for whether it is possible to achieve the same effect as ReadyBoost via either enabling (and installing) ReadyBoost or using third party software.
Reasons for using Widows Server 2008 as a development environment on a laptop:
64-Bit, so you get the full use of 4GB RAM.
SharePoint developer, so you can run SharePoint locally and debug successfully.
Hyper-V, so you get hardware virtualisation of test environments and the ability to demo full solutions stored in Hyper-V on the road
So all of that equals: Windows Server 2008 (64) on a laptop.
Now because we are running Hyper-V, we require a large volume of disk space. This means we are using 5,000 rpm 250GB HDD.
So we are on a laptop, we are not able to use solid state HDD, and we only have 4GB of RAM and the throughput of a laptop motherboard rather than a server one... all of which means we are not flying... this thing isn't a sluggard but it's not zippy either.
Windows Server 2008 is based on the same code base as Vista. Vista features ReadyBoost, which enables USB 2 flash devices to be used as a weak cache for system files, which visibly increases the performance of Vista. As the codebases are similar, it should be possible for ReadyBoost to work on WS2008, however Microsoft have not shipped or enabled ReadyBoost in WS2008.
Given that we are running WS2008 on a laptop as a development environment, how can we achieve the performance gains of ReadyBoost through the use of flash devices in Windows Server 2008?
For the answer to be accepted it must outline an end to end process for achieving the performance gain.
Answers of 'No' will not be accepted as I understand some third party tools achieve some of the functionality, but I haven't seen a full end-to-end description of how to get going with them.
With Virtual machines, the answer to "do you really need so much memory" is a resounding YES. Trying to run 4-6 virtual machines eacch configured with 512MB or more really stresses out the system.
The ability to use ANYTHING as additonal virtual memory is key.
Is everything that's installed
64bit?
Do you have hardware virtualization
capabilities and is it turned on in
the bios?
Have you enabled superfetch?
Turn of desktop experience.
And last but not least, have a look
at this article and see if it
gives you any pointers.
Too add: It doesn't look like there is a reasonable way of using ReadyBoost on WS2008
OK, so this isn't quite ReadyBoost but the end result should be quite similar. Here is a video on youtube you can follow on how to do this on Vista - WS2008 should be no different.
http://www.youtube.com/watch?v=A0bNFvCgQ9w
Also, you may want to upgrade the hard drive on your laptop:
Recommend ST9500420ASG 500GB 7200RPM 16MB SATA w/ G-Shock Sensor