General :: Measure Kernel Space Time And User Space Time?
Nov 28, 2010measure kernel space time and user space time?
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General :: Division Of Logical Memory Space In To User Space And Kernel Space
Jan 4, 2010Logical Memory Space of 4GB is divided in to 3GB User Space and 1GB Kernel Space. Always. Correct?
1. How can we change it? (just changing value of PAGE_OFFSET is okay?)
2. If system have only 256MB of memory (embedded system) and suppose Kernel Modules eat away all the memory during boot. User space will be left will no memory. Is this case possible?
General :: Time Function In Kernel Space?
Jan 26, 2010I manage to use the function "time" and "localtime" in gcc.But while I used it in a module in kernel space the above 2 functions are giving error.Even in kernel space time.h header file is not identified. tell the similar time function which can be used in kernel space
View 1 Replies View RelatedGeneral :: Time Oriented Program In Kernel Space?
Jan 28, 2010I have written a programme in gcc
#include <time.h>
#include <stdio.h>
int main(void)
[code]...
General :: Calling User Space Callback Function From Kernel Space?
Sep 22, 2009I am writing device driver in which i have to call callback function from kernel space, which are saving my data. But the callback functions are in userspace. While accessing them i am getting segmentation fault.
View 1 Replies View RelatedGeneral :: Short A Time Can Time (system Program) Measure?
Apr 15, 2010I'm just wondering what the limits for time are. I have a program that always takes exactly 20 ms, so I assume this is the lowest it can measure, but I want to see if there's some sort of documentation of this.
View 3 Replies View RelatedProgramming :: Passing Data Between Kernel Space To User Space In Asynchronous Way
Dec 13, 2010I am developing a I2C CDROM client driver. The CDROM firmware supports TOC information read through a I2C command. It sends the TOC information in burst ( Interrupts a GPIO pin when it is ready ) and my CPU does a I2C read to read the TOC. When the CDROM firmware finishes sending the last data burst , it informs my CPU that it is done with the TOC, by a flag in the last data burst. I would like to know, which is the most efficinet way I can send these TOC information to userspace?
View 4 Replies View RelatedProgramming :: Function In Kernel Space Called Form User Space
Jul 7, 2009I wanna write a file in kernel space but from my searching I can to know that instead of writeing file in kernel space ,I can write data to user space by copy_to_user space.
But link is missing ...I dont know how will my user space will access kernel space means my function in kernel space which will do copy_to_user /....How my user space function will call my kernel level function ..
Can any one of you provide me with some example file which are doing this .I know every char driver is using it ...but i could not trace back how user level function is accessing it ...i m confused between user space and kernel space.
Programming :: Call Socket Prog Code Written In User Space From Kernel Space?
Jul 14, 2009How to use execv from kernel space to call a user space program writtenfor socket prog.
I tried to write code for socket in kernel but its not working.
Socket code in kernel is also needed.
Programming :: Signal From Kernel Space To User Space?
Jul 21, 2011I have the following requirement in my module. The driver gets some data from the external device. After getting 1MB of data it has to send it to the user space application. What is the best thing to implement for this in driver.? Is it ok to implement like, after getting data, the driver will send a signal to the user space application. Then the user space application sends an ioctl to read the data. Is there any alternate, that the driver directly sends the data without the user space application asks for it.?
View 4 Replies View RelatedGeneral :: Install 12, Every Time Chose The Space To Install It, It Says That There Is No Enough Space To Install It?
May 11, 2010I have 40gb of hd and I want Xp and fedora on it. I installed Xp first and now I want to install Fedora 12, every time I chose the space to iinstalll it, it says that there is no enough space to install it, although the xp just took less than 2gb of the disk. How can I resize it so that there is enough space?
View 8 Replies View RelatedGeneral :: Takes Long Time While Booting - Enabling Swap Space ?
May 9, 2010While booting Linux it takes ages for 'enabling swap space'
I have allocated swap space twice that of the RAM.
Is there a way to fix it? What should I do to avoid this in the future installs?
General :: Virtual Space Seen By Each New Process In User Space?
Jun 21, 2010In a 32-bit system, max memory addressable is 4GB. Now Linux kernel does memory mapping division of 1GB for kernel address space and 3GB for user address space. That means 4GB of virtual address space is divided between kernel (1GB) and user (3GB).
Q1. All virtual mapping utilizes the available physical RAM without any division? I mean to say that if RAM is 512MB then a page in kernel space can lie any where RAM (leave aside old PCI dma accesses)? (How this fits to fact that kernel memory is non-pageble)
Q2. If a process is created in user space, it has visibility 4GB address space or 3GB address space?
General :: Kernel Module Run In It / User Space?
Oct 25, 2010I'm pretty new to this whole (micro)kernel architecture story.
Im wondering if a kernel module is running in kernel or in user space?
Is a driver running as kernel module slower than a driver build into kernel?
If so, are there some current articles, benchmarks?
General :: Difference Between User And Kernel Space?
Jul 12, 2010what difference between user and kernel space.
View 2 Replies View RelatedGeneral :: Shared Buffer Between User And Kernel Space
May 3, 2010I need a shared buffer between user and kernel space. I read that one way is to allocated buffer in kernel and then call mmap from the user space. I searched for an example but couldn't find something useful. If you know, could you please send me any links or sample code that does this..
View 1 Replies View RelatedGeneral :: Measure GUI App Startup With Time(1)
Mar 12, 2010I want to measure the startup time of any GUI app (e.g. firefox) using the time(1) command. However, timing is measured until the app is closed, which has to be done manually by exiting it or clicking X.
How can I get the app to load, terminate immediately and give me the startup time?
Ubuntu :: Get A Space Between The Date 2010 And The Time 12:29:29pm?
Jul 31, 2010echo "testavast`date +%m-%d-%Y%l:%M:%S%P`" | cat >> /home/lance/report/update.txt
i get testavast07-31-201012:29:29pm
how do i get a space between the date 2010 and the time 12:29:29pm
General :: Measure Script Execution Time?
Jan 4, 2011In bash shell, is there a simple way for me to monitor the time taken to run a script and output the time taken?
View 1 Replies View RelatedGeneral :: Get The Values For The User Time And System Time For A Process?
Aug 4, 2009get the values for the user time and system time for a process.i have tried getrusage to get values of ru_utime and ru_stimebut these don't seem to be correct
View 3 Replies View RelatedUbuntu Security :: .encryptfs Folder Is Taking Up So Much Space - Getting Notifications Every Time Log In
May 20, 2011When I reinstalled ubuntu I chose to encrypt my home folder (something that i've never done before) but now that I know it doesn't really make a difference i'd like to decrypt it because the .encryptfs folder is taking up so much space i'm getting notifications every time I log in.
View 7 Replies View RelatedFedora :: Compiz Fusion - Every Time Go To Kde Application Launcher It Takes Back To Space 1
Mar 24, 2010I have updated to FC11 a few months back and after I got my desktop effects going I notice that every time I go to my kde application launcher it takes me back to space 1. I could be in space 6 but as soon as I go to the application launcher to open a new application it takes me back to space 1 and I have to manually move the application to desktop 6. This only happens when compiz fusion is enable...
View 4 Replies View RelatedKernel :: Syscall Accessing User Space?
Feb 22, 2010If the calling process passes me the virtual address of an its array for example, how can I access it without using copy_from_user?
View 2 Replies View RelatedGeneral :: Find Out How Much Time An Already Running Process Is Spending In User And Kernel Spac?
Jun 8, 2011I am currently struggling with one of my tasks.I was asked to find a way how to determine how much time an _already running_ process is spending in user and kernel space.E.G. <some tool> <pid>[Control] + [c]<pid> spent 12.1 seconds in user and 1.52 seconds in kernel space.Does something like this exist? Basically I guess I am looking for something similar to time, except that the process is already running.So..a) Is there a tool which fulfills this task?b) Is there a way to write your own software which does the job? Is it even possible to code something I am looking for?I recently found strace -c -p <pid>, but well, this is not exactly what I was looking for.
View 3 Replies View RelatedProgramming :: Make A (user Space )process Pre Emptive / In 2.6 Kernel?
Dec 10, 2008I am writing a program which i dont want the kernel scheduler to preempt before certain time duration. I am using the system call sched_get_priority_max to set the maximum priority. However it is not producing results.
View 3 Replies View RelatedProgramming :: Measure Time Of N Processes?
Oct 24, 2010how can I measure time of N processes and N threads and then compare this time to prove that threads are faster than processes. understanding C code, or also for some good way to measure time of N processes and N threads for C.
View 5 Replies View RelatedProgramming :: Measure CPU Time Spent On A Code Block (with C Or C++)?
Jul 31, 2011I have a C program like this:
...
CODE_BLOCK;
...
I want to know how much CPU time spent on CODE_BLOCK. Since the process executing CODE_BLOCK may be preempted during execution, this CPU time may not be equal to the (wall-clock) time elapsed from the beginning of CODE_BLOCK to the end of it.
Ubuntu :: Measure Time Needed To Copy A File From One Place To Another?
Apr 24, 2010I was wondering if you could help me how to measure the time needed for Ubuntu to copy a file from one place to another.
View 2 Replies View RelatedGeneral :: Scripting - Cp A List Of Files Which Starts With - Or Space Without - Or Space?
Oct 14, 2009I have a list of files in a directory which starts with - or have space.
I need to copy them back without the space or -?
linux1[sim]% ls linux1[sim]% cp ./-* ./*
General :: Use Free Space To Extend The Space Of A Drive?
Jul 5, 2011My system is dual boot with win7 and ubuntu. I have free space of around 10 gb. I want to add this free space to my ubuntu drive. How can i do that?
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