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cl-netbox

1:00 PM

@Fabby :D :D :D

Fabby

:-)

It's another MoBo and nVidia card he got when another friend upgraded his...

2 hours later…

traducerad

2:36 PM

I am running code (which spawns 2 processes) on a quad core CPU. Is there a way for me to say "the parent proccess should run on core 1, the two children should share core 2"?

terdon

@traducerad I doubt it, but why would you want that? Why do you care which core runs what?

traducerad

@terdon Wikipedia states:

For example, hardware or software considerations may require that only one particular CPU respond to all hardware interrupts, whereas all other work in the system may be distributed equally among CPUs; or execution of kernel-mode code may be restricted to only one particular CPU, whereas user-mode code may be executed in any combination of processors.

Multiprocessing systems are often easier to design if such restrictions are imposed, but they tend to be less efficient than systems in which all CPUs are utilized

So I'd like to try this out. I am running my code on an embedded device, so I'd like to do some experiments

terdon

@traducerad That sounds like the sort of thing managed by the kernel. It is a discussion of how the hardware architecture has been wired. I don't think you can affect this from userland.

traducerad

@terdon I am willing to dive into kernelland

terdon

In any case, that's the sort of thing you might want to ask about on Stack Overflow. Even if it is possible, the details will depend on the language you're coding in.

traducerad

2:42 PM

Hmmm

The Linux kernel does quite some heavy lifting. When writing a muliprocess software in userspace which is composed of multiple threads all those have to be scheduled

Do threads have the same priority as processes?

dessert

2:56 PM

@traducerad GNU parallel runs one job per CPU core in parallel by default and you can change this behaviour, though not define which process runs on which core.

Ubuntu Questions on U&L

3:54 PM

Q: Is a swap a partition but not a file system?

Is a swap a partition but not a file system? Is that the reason why df doesn't show it? Is there a command which can list all the partitions (whether they hold file systems or not)? Thanks. $ df -h Filesystem Size Used Avail Use% Mounted on udev 3.9G 0 3.9G 0% /dev tmpf...

1 hour later…

Byte Commander

4:59 PM

@traducerad You might want to check out the taskset command.

Ask Ubuntu Meta

Q: What i wrong with this question? And why is it closed by mods? Why answers don't make sense?

Error with 'tar' commad, "Cannot open: No such file or directory" Can Someone explain what is wrong with this question, and why any discussion is shut like that by moderators or community leaders? I am facing this problem, extracting an archive and the tar returns these errors. I wget the archi...

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6 hours later…

Kaz Wolfe

10:31 PM

poke

Ubuntu Questions on U&L

11:15 PM

Q: Console login enter repeats after entering username

I've been a long time Linux user and today I've come across a problem that just baffles me! This is happening on an Ubuntu 18.04 LTS fresh install for my nephew, I'm a long time Gentoo user myself and generally a console ninja. My first habit on Linux issues is to switch to a console, login and...