New subject: How to increase maximum user cpu usage allowed on a multi core system?

11 Mar 2015

      On Wed, 11 Mar 2015 13:32:09 +0100
poma pomidorabelisima@gmail.com wrote:
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You still haven't provided basic information about the processor,

thus 'lscpu' or a similar command.
$ lscpu
Architecture:          x86_64
CPU op-mode(s):        32-bit, 64-bit
Byte Order:            Little Endian
CPU(s):                6
On-line CPU(s) list:   0-5
Thread(s) per core:    2
Core(s) per socket:    3
Socket(s):             1
NUMA node(s):          1
Vendor ID:             AuthenticAMD
CPU family:            21
Model:                 2
Model name:            AMD FX(tm)-6300 Six-Core Processor
Stepping:              0
CPU MHz:               3500.000
CPU max MHz:           3500.0000
CPU min MHz:           1400.0000
BogoMIPS:              7023.57
Virtualization:        AMD-V
L1d cache:             16K
L1i cache:             64K
L2 cache:              2048K
L3 cache:              8192K
NUMA node0 CPU(s):     0-5
...

Moreover you still haven't provided the difference between
"I'm running Fedora 21 with a custom compiled kernel,

3.19.0-1.20150211.fc21.x86_64." and stock Fedora kernel -
3.18.8-201.fc21.x86_64, i.e.
   diff /boot/config-3.18.8-201.fc21.x86_64 /boot/3.19.0-1.20150211.fc21.x86_64
I can do this but I think it is too large for a message.
There are 1532 lines of output from that command.
...

Also you haven't mentioned whether the same happens with the stock

Fedora kernel.
Yes, it did.
...

And you haven't explained why you use a custom kernel, and why

particularly 3.19 kernel.
To remove all the generalizations that have to be in stock kernels so
they can work for everyone.  It greatly speeds compilation to not do
all those drivers that I don't need.  Sound cards I don't have
Latest that created packages without errors.  I'll be upgrading to 4.0
kernel shortly.  https://bugzilla.redhat.com/show_bug.cgi?id=1199312
...

Etc.

How anybody can help in this way, man.
I don't see how those have any relevance.  All the answers to them
would do is be noise or distraction.  This is at a meta level above
that, about the design and control level, rather than the implementation
details.  I guess I am assuming that the kernel programmers have done
their job, and the kernel functionality is abstracted from the
underlying hardware.  Especially for x86 architectures.
I think Heinz has put his finger on the issue in his response: a single
process is limited to a single core.  But, if that single process can
spawn other processes, which is what 'make -j6' should be doing, why
would that be true? I'll be following up in my response to him.
Thanks for taking an interest, and I'm not trying to be hostile, but I
honestly don't see how answering your questions helps.

Re: How to increase maximum user cpu usage allowed on a multi core system?