Questions tagged [cpu]
The CPU (Central Processing Unit), is the chip in the computer that actually performs the operations and calculations that are done as a program runs. It is essentially what executes a program.
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Restrict all already running processes to a range of CPU cores
I've got an AMD 7950X3D CPU which has 32 total logical cores, 16 of which (0-15) have access to extra cache. To optimize my system for gaming while multitasking I want to run Steam and all the ...
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CPU Operational Load on WSL slows down entire computer
I'm running a Dell XPS15 with 64 GB Ram and a i7-12700H (6 performance cores, 8 efficency cores). I just recently (read: 2 weeks ago) did a clean upgrade and reinstall to Windows 11 with all up-to-...
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raspberry pi specific script to run commands upon cpu reaching defined temperature
i just need certain commands (that control fans and light up a warning LED) to be run when cpu temperature exceeds a certain threshold and other scripts if and when they finally return to below ...
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CPU IDLE low as results of bad disks is it the case here
Low CPU IDLE can be caused by a variety of factors, including:Insufficient RAM or slow Hard Disk Drive
but in our RHEL server RAM memory have enough RAM but from dmesg we found couple errors about the ...
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Cumulative CPU time across reboots
How can I record and view cumulative CPU time on system across reboots? Essentially, it should be like the TIME+ column of top, but not per process. In other words, like vnstat, but for CPU time. I am ...
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What does QNX's top CPU idle percentage really means?
I am using QNX (ARM Cortex A53 with FOUR cores) and when I do top, I have the below. According to the below idle percentages for each of the core, I'd like to confirm CPU/Core 0 is the most idle, ...
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Non-boot CPUs are not disabled (It seems there is a bug in new "6.2.0-26-generic" kernel)
I use Ubuntu 22.04 with no issues for a while, but recently I can't suspend the OS and it gives me the following error and either hangs with a blank screen or shows up the system login screen:
Non-...
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Are Intel or AMD processors generally regarded as "better" for Linux [closed]
Are there any differences between Intel and AMD processors in how Linux runs? Specifically in terms of performance, optimizations, and driver support?
To simplify things, I am just talking about the ...
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CPUIdle: what could be the reason for a core refusing entering the C6 state though the kernel requests so?
I'm trying to measure the time that a core spent in each c-state during a workload run and found a weird phenomenon: the kernel requests a core to enter C6, but the hardware only stays in C1.
The ...
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How to get resource usage from docker build command
I need to track the memory and CPU usage of BUILDING (NOT RUNNING) a docker container.
I have tried using psrecord (along with the include children option) on the PID for the terminal I run docker ...
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Why cpu number is limited?
seeing this log:
APIC: NR_CPUS/possible_cpus limit of 64 reached.
but I didn't set any limitation on CPU number.
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Unable to find any information about TLB on my computer or obtain information about hardware counters about TLB
The Ubuntu version I am using is Ubuntu 18.04.6 LTS, and the kernel version is 5.4.0-148 generic. My processor is 12th Gen Intel (R) Core (TM) i7-12700.
I would like to know the number of TLB ...
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In a computer with two CPUs, how can I get the physical address of local memory of each CPU?
My computer has the following specifications
2 Intel CPU x86_64
Total 8GB memory (4GB per CPU)
O/S is Rocky Linux 9
I want to reserve 1GB of memory per CPU using the memmap parameter in grub. I ...
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My Acer aspire x1700 running linux mint 21.1 sometimes freezes up and is slower than Windows 7 was
lscpu returns this:
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Address sizes: 36 bits physical, 48 bits virtual
Byte Order: ...
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"Hello world" to pixels -- everything between OS, driver, and hardware (CPU, GPU, PCIe, USB-C to display)
Can someone explain "Hello World!" in relation to the modern stack of software and hardware on a modern Linux or Unix machine? Doing a $ strace on the binary generated by following ...
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Get CPU core id executing a process which suddenly exits
In Linux, in a multi-core processor, ps, top and similar tools can show the CPU logical core id running a specific process. If the process runs for a certain amount of time, it's easy to identify it ...
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How Linux Pressure Stall Information actually works
I have been doing some background reading about PSI introduced in Linux 4.20. PSI gives an indication of how contended resources such as CPU, memory and IO are. This can be a very useful metric to ...
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Any ready made script to pin the IRQ to the optimal CPU?
I'm not a expert by any means and I worry about doing wrong stuff... is there a standard / approved way to just run a script and have my interrupt tuned correctly on ubuntu 18.04 ?
I also have ...
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Help with Interpreting and Resolving Irregular Hardware Error Messages on Debian GNU/Linux System
I have a small problem here that I hope your kind help with. Recently these messages started appearing in my notification tray:
Message from syslogd@oldsage at Apr 30 12:25:28 ... kernel:[9655.826192]...
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lscpu list different max cpu freq
Is this a bug from lscpu?
How to fix it?
~$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
Address sizes: ...
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CPU max MHz showing below base clock
I have a lenovo thinkpad e15 with a i7-10510U with baseclock of 1.80GHz when I run
lscpu | grep CPU it shows.
CPU op-mode(s): 32-bit, 64-bit
CPU(s): 8
On-line ...
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Question about Context Switching on x86 in xv6 OS
I'm reading OSTEP for my Operating Systems course, and I have a question from Chp.6.3:
Note that there are two types of register saves/restores that happen
during this protocol. The first is when the ...
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Difference between cores and logical processors
I have a question about core and logical processors. So, my computer has 1 CPU with 2 cores and 4 logical processors. Does this mean that my computer has 4 threads, 2 threads for every core? Than why ...
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What is the exact source of Architecture info in lscpu command
Tl;dr
I need to mock info about CPU architecture on the server for testing purpose. The only way that I can achieve it, is by changing info source about CPU architecture, that is used by lscpu command ...
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Why aren't the CPU core numbers in sensors output consecutive?
The core number is 0,4,8,.....39 in the sensors command.
Why not 0,1,2,3,4.....?
foo@foo-linux:~$ sensors
coretemp-isa-0000
Adapter: ISA adapter
Package id 0: +73.0°C (high = +80.0°C, crit = +100.0°...
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Calculate total CPU usage
I have following specs:
CPU(s): 2
Thread(s) per core: 2
Core(s) per socket: 1
Socket(s): 1
A process is using (according in top) 50%. How much is the total usage?
Is ...
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Single core slow on i9 vs i3
Upgraded CPU from Intel Core i3-8350K to i9-9900K.
Intel Core i3-8350K @ 4.00 GHz 1 Processor, 4 Cores, 4 Threads.
Base clock rate 4.00GHz
GenuineIntel Family 6 Model 158 Stepping 11
Intel Core i9-...
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System unresponsive even when running command with nice
Debian 10. I am trying to render with blender in the background, like so:
nice -n 19 blender -b --python my_script.py
This renders to a file using the GPU. When rendering, I can see GPU usage spike ...
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CPU freq locked to 800mhz shortly after boot (ps15 thinkpad)
I've got a frustrating mystery and I'm hoping that someone can point me in the right direction.
Problem:
Under load, my system doesn't increase CPU frequency to meet demand after some period of time ...
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18th core on my 13900k is experiencing constant 43% load, how to find the root cause of this behaviour
I am very confused by the load on my i9-13900k. It's always the same 18th core and only that one specific core.
I tried to kill every process running on that said core but the load still persists. Can ...
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How do i list all consuming program by cpu, memory
I wanna list down all consuming cpu, memory programs.
there are bunch of top and questions about it, but all of them not list them by programs.
like for example a python webservice could spawn ...
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Set affinity of a process using TASKSET or sched_setaffinity() to a processor core isolated using CPUSET
First, let me give a background of what I am trying to achieve. I know how to isolate a particular CPU using boot param (isolcpu and nohz_full; the housekeeping subsystem setup).
But as per my ...
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rcu_sched vs rcu_preempt CPU stalls
I have basic query regarding the RCU CPU stalls, sometimes there is message like INFO: rcu_sched self-detected stall on CPU, and sometimes it's INFO: rcu_preempt detected stall on CPUs/task, what is ...
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Inconsistent results in CPU benchmarking with Hardinfo: Is the tool outdated and are there better alternatives for Linux users?
This program is the only CPU benchmarking application on Linux that works for ordinary users. After testing it, I wonder if it is relevant because I compared the results between two ways to execute ...
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CPU temperature often reaches 100°C
I have a new desktop computer with Intel i7-12700 32GB RAM.
I am doing build code stuff, I use the sensors command to check CPU temperature, and I found most of the cores are @ 100C.
Is that normal?
...
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CPU warning every time I boot
Every single time I boot my Linux distro I get a message that says:
RETBleed: WARNING: Spectre v2 mitigation leaves CPU vulnerable to RETBleed attacks, data leaks possible!
Is this a serious security ...
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How to transfer files from host OS to qemu running kernel only?
I have used the instructions found in the readme.txt file from here to run qemu-system-riscv64 for T-HEAD's C906 processor. QEMU successfully boots into the kernel, but there's not much functionality (...
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Possible to pause console operation?
I have many working jobs running on different consoles.
They almost occupied all the CPU usage, which caused me hard to control the system ( very slow response time )
Is there any way to pause these ...
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Want to configure /proc/irq/$irq/smp_affinity_list but not sure values are right?
I am following this guide here to get 10Gbps line rate on Linux.
The author mentions using this script to set your own affinity pinning for CPU irq:
client$ (let CPU=0; cd /sys/class/net/eth2/device/...
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Enable E-cores in linux
I have a rented server with having Intel 12th Gen Alder Lake Processor. I guess the E-cores are disabled.
When I run lscpu --all --extended, I get the following output.
I don't see a core with max ...
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Persistently disable Intel Turbo Boost
Through the magic of piezoelectric phenomena, I experience "coil whine" when moving the mouse.
Turns out said coil is energized by the CPU, and that the Intel driver enabling Turbo Boost ...
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Why ping results varied with the CPU load
I am trying to ping between two PCs running Ubuntu 20.04 connected via a Layer-2 switch.
My goal is to get "nearly" stable ping latency.
Similar to other people, I figured out that ping ...
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Find out which process is using CPU 0
I've applied CPUAffinity to certain systemd services. I've checked Cpus_allowed_list from /proc/PID/status, and it works fine.
Now I want to find out which process is using CPU 0 or CPU 1, how can I ...
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How to get CPU statistics PER PROCESSOR on AIX without requiring root privileges?
I want to get the per processor statistics for my AIX machines. I can use the ‘sar -P ALL 1 1’ (Documentation) command but it requires root privileges.
Is there a command that can give me PER ...
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How to make the top command calculate the CPU usage per second?
I am using top in Solaris mode via top -d 1 and it shows that one of my processes is using around 45% of CPU.
Question:
Since I'm using -d 1 does that mean that process is using around half of my ...
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Restrict NFS to only run on certain cores
I have an application that likes to use the very first core in a core complex. For example, assuming CPU has CCX of 4, it would run the load on core 0,3,7,11,…. This process is time sensitive and ...
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How to know CPUxx is which socket?
I have two sockets (CPU), How to know CPU41 as below belongs to which CPU/socket?
hostname kernel: CPU41: Package temperature above threshold, cpu clock throttled (total events = 438285593)
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Processes ignore global CPUAffinity settings
I am setting global CPUAffinity via /etc/systemd/system.conf. See snippet below:
root@PC1-03:~# cat /etc/systemd/system.conf
# This file is part of systemd.
#
# systemd is free software; you can ...
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systemd-journal is using 100% cpu
This is the result of top command
I caught it at 99.7% but It even uses 170%. this is the output of journalctl
I thought it is something related to Bluetooth, so I turned it off but still got the ...
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QEMU emulating two CPU archs
As I know, x86_64 Linuxes are capable of running x86 programs. I wonder if it would be possible to emulate it using QEMU.
I am using proot and hoping to proot into such said system.
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