On top of a dual quad core physical host, I would like to run a single VM with 8 virtual CPU (if possible) or at least 4 virtual CPU - for the purpose of scientific computing. I have investigated what the market has to offer at this date and it seems that VMWare Server 2.0 is limited to 2 virtual CPU. Microsoft Virtual Server 2005 RC2...
Is there a progamatic method to set CPU affinity for a process in c/c++ for the linux operating system. ...
Presumably there is a library or simple asm blob that can get me the number of the current CPU that I am executing on. ...
Could anyone recommend me some documents to illustrate their differences please? I am always confused about the differents between multi-CPU, multi-core and hyper-thread, and pros/cons of each architecture in different scenarios. EDIT: here is my current understanding after learning online and learning from others' comments, could anyon...
We've got a Linux-based build system in which a build consists of many different embedded targets (with correspondingly different drivers and featuresets enabled), each one built with another single main source tree. Rather than try to convert our make-based system to something more multiprocess-friendly, we want to just find the best w...
( I ask because it was before serious SMP and multicore that I studied OS. I like to have some vision of how code is being executed. ) If I have a multicore x86 CPU booting directly into my program. Can someone recommend a website which describes what assembler commands do I have to control affinity? ...
The Machine is Dual-Core, the OS uses a Multi-Processor kernel. In order to run some performance assessments, I want to set the thread-affinity of the JVM to a single core. However, I am worried that I will get skewed performance measurements as the JVM may be unaware that it is now constrained to a single core, but still using multi-pro...
I have two CPUs on the chip and they have a shared memory. This is not a SMP architecture. Just two CPUs on the chip with shared memory. There is a Unix-like operating system on the first CPU and there is a Linux operating system on the second CPU. The first CPU does some job and the result of this job is some data. After first CPU fin...
In real mode on x86, what instructions would need to be used to run the code on a different processor, in a multiprocessor system? (I'm writing some pre-boot code in assembler that needs to set certain CPU registers, and do this on every CPU in the system, before the actual operating system boots.) ...
I'm looking for a simple process-based parallel map for python, that is, a function parmap(function,[data]) that would run function on each element of [data] on a different process (well, on a different core, but AFAIK, the only way to run stuff on different cores in python is to start multiple interpreters), and return a list of resu...
I'm studying Erlang's process model at the moment. I have hit a snag in a tech report (section 3, paragraph 2) on Erlang: This explains why it in some cases can be more efficient to run several SMP VM's with one scheduler each instead on one SMP VM with several schedulers. Of course the running of several VM's require that the ap...
I am looking for a hardware, which must run about 256 computationally intensive real-time concurrent tasks in 24 hour mode (one multi-threaded C application). Each task takes about 40-50 MFLOPs, so all tasks require about 10 GFLOPs. CPU-RAM speed is insignificant. All tasks must be managed by a Linux Kernel (32 bit, with SMP). I am look...
I am trying to squeeze the most performance out of a Linux block driver for a high-end storage device. One problem that has me a bit stumped at the moment is this: if a user task starts an I/O operation (read or write) on one CPU, and the device interrupt occurs on another CPU, I incur about 80 microseconds of delay before the task resu...
I am actually on my project on compiler with SMP, and want to code with pthreads and heard about many parallel things open mpi and so on, So to start with how this thread is allocated to core while calling pthread,Is there any way to give threads to different cores by pthreads? ...
In Windows, I can set the processor affinity of driver code using KeSetSystemAffinityThread, and check which processor my code is running on using KeGetCurrentProcessorNumber. I'm trying to do something similar in a Linux kernel module, but the only affinity calls I can see are for userland processes. Is there any way to do this, so tha...
hi, consider a kernel tasklet scheduled and executing the tasklet function. Is there a way to know which core the tasklet is running ? I mean is there a function / variable to know at which core the tasklet is running at. Architecture is arm. Thanks! ...
on a project I am working on, we are seeing out-of-order issues in certain circumstances on a SMP system when we are reading a UDP stream from the network. We can see it arrives from the network in order by sniffing off a hub connected between the sender and receiver. However sometimes it appears to arrive out of order when read from the...
I am learning multi-thread programming; and whilst practising mutex, I notice that it seems doesn't work correctly on my dule-core laptop. The mutex code is at http://pastebin.com/axGY5y3c The result is as below: count value:t[0]1 count value:t[1]1 count value:t[2]2 count value:t[3]3 count value:t[4]4 The result shows that seemly t...
The Linux Kernel is said to be SMP. It is said that processes and kernel threads shall be distributed across processors. Does all Linux distribution like fedora13, ubuntu 10.04 Lucid by default enable SMP Linux? On an SMP Linux, which is better to follow- a) multi-process approach versus b) multi-threading approach Does pthrea...
I am currently working on a project about setting process to one core in linux environment. I use sched_setaffinity to do this job and I wonder whether there are some functions provided by linux to get which core the process is running on. I use top command and find it could get this info using j option. So i am sure there are some wa...