Questions tagged [cpu-usage]

The amount of processing units of the CPU used to execute a task and how long it takes.

Filter by
Sorted by
Tagged with
56 votes
4 answers
130k views

What does 'nice' mean on CPU utilization graphs?

On Ubuntu server load graphs I see 4 types of CPU consumption: User, System, Nice and Idle. What does Nice type mean?
Niro's user avatar
  • 1,451
53 votes
6 answers
144k views

Linux CPU usage and Process Execution History

Is there any way to see what process(es) caused the most CPU usage? I have AMAZON EC2 Linux which CPU utilization reaches 100 percent and make me to reboot the system. I cannot even login through SSH ...
pmoubed's user avatar
  • 643
42 votes
8 answers
90k views

High CPU utilization but low load average

We are running into a strange behavior where we see high CPU utilization but quite low load average. The behavior is best illustrated by the following graphs from our monitoring system. At about 11:...
K Erlandsson's user avatar
34 votes
5 answers
32k views

What does %st mean in top?

Here is an example from my top: Cpu(s): 6.0%us, 3.0%sy, 0.0%ni, 78.7%id, 0.0%wa, 0.0%hi, 0.3%si, 12.0%st I am trying to figure out the significance of the %st field. I read that it means steal ...
Ben's user avatar
  • 565
29 votes
2 answers
10k views

Is there a Windows equivalent of Unix 'CPU steal time'?

In order to assess performance monitoring accuracy on virtualization platforms, the CPU steal time has become an increasingly relevant metric - see EC2 monitoring: the case of stolen CPU for an ...
Steffen Opel's user avatar
  • 5,648
28 votes
2 answers
30k views

How are CPU time and CPU usage the same?

In the Wikipedia page for CPU time, it says The CPU time is measured in clock ticks or seconds. Often, it is useful to measure CPU time as a percentage of the CPU's capacity, which is called ...
Jasmine Lognnes's user avatar
26 votes
5 answers
76k views

check history of cpu/memory usage in ubuntu?

Is there a way for me to review cpu or memory usage on my ubuntu linux server? I've noticed my server (lamp set up) being slow at times, but by the time I log in as root and run a PS command, ...
learningtech's user avatar
  • 7,445
25 votes
4 answers
19k views

"Peaky" CPU Usage on Domain Controllers

We have two Windows Server 2008 SP2 (sadly not 2008 R2) Domain Controllers in a small 150 client domain that are exhibiting very "peaky" CPU usage. The Domain Controllers both exhibit the same ...
user avatar
23 votes
3 answers
31k views

Kill process with high CPU usage after X time? [closed]

Running Linux I have a few processes which tend to crash occasionally (game servers), which end up using 100% cpu. I'm looking for a program or script to check the cpu usage of a list of processes by ...
user30153's user avatar
  • 231
23 votes
3 answers
10k views

Prioritise ssh logins (nice)

Is there a preferred way to set "nice" for sshd? I need priority given to sshd such that I can login and easily fix stuff when something has gone wrong (eg DoS, badly behaved processes, etc)
s29's user avatar
  • 348
19 votes
8 answers
57k views

kswapd often uses 100% CPU when swap is in use

Most of the time when my computer starts to need swap, I see a massive spike in CPU usage (kswapd0 is consistently using 99%-100% CPU). According to top, the time is spent in sy (system/kernel) not wa ...
Zaz's user avatar
  • 813
18 votes
1 answer
14k views

Taskset not working over a range of cores in isolcpus

To preface I'm using Debian Wheezy with kernel 3.2 on an AMD64 chipset. My machine has two Xeon E5-2690 cores. I set up the boot parameters so that all the cores on one CPU are dedicated to a single ...
user79126's user avatar
  • 469
17 votes
7 answers
6k views

How often do you restart a heavily-utilized Windows Server 2008R2 Remote Desktop Server (VM)?

Note: I've read How Often Do Windows Servers Need to be Restarted? but this question pertains to our Remote Desktop server specifically. We have a Windows Server 2008R2 server - a VMware ESX VM - ...
tacos_tacos_tacos's user avatar
17 votes
2 answers
23k views

Use of CPUQuota in systemd

I am trying to put a hard limit in CPU usage for a dd command . I have created the following unit file [Unit] Description=Virtual Distributed Ethernet [Service] ExecStart=/usr/bin/ddcommand ...
SteveGr2015's user avatar
16 votes
1 answer
161 views

How to start a program when CPU percent reaches X

I have been having very intermittent problems with an ASP.NET v 4.0 application happens maybe ever 4 days, what happens is the CPU will spike to 75% and sometimes is will run fine until the end of the ...
Anthony Fornito's user avatar
15 votes
5 answers
105k views

MySQL process goes over 100% of CPU usage

I'm experiencing some problems with my LAMP server. Recently everything became very slow, even though visitor count on my websites didn't change to much. When I run top command, it says that MySQL ...
Temnovit's user avatar
  • 1,127
15 votes
3 answers
23k views

How to monitor CPU usage and performance on a Hyper-V server with several VM's

I have a server that is running Windows 2008 64 bit Hyper-V, with 8 gigs of RAM and Intel Xeon X3440 @ 2.53 Ghz, which gives me 8 logical cores in the performance monitor on the host system. I have ...
Bjørn's user avatar
  • 337
14 votes
2 answers
25k views

stress-ng: Simulate specific cpu percentages

Linux environment: Debian, Ubuntu, Centos Goal: Test monitoring program that set alarms and trigger different alarms at different cpu percentages. ex: (30-50%), (51-70%) and >90% So I need a cpu ...
AJN's user avatar
  • 446
13 votes
4 answers
8k views

ps aux hanging on high cpu/IO with java processes

I'm having some issues with java process and nrpe checks. We have some processes that sometimes use 1000% cpu on a 32 core system. The system is pretty responsive until you do a ps aux or try to do ...
Mike's user avatar
  • 22.5k
13 votes
5 answers
30k views

Why is idle windows VM using so much CPU?

I have 2 VMs running as guests on a KVM virtualization platform running on Ubuntu 10.04. One VM is an Ubuntu 10.04 system, the other is a Windows 7 system. When both machines are completely logged ...
user avatar
12 votes
4 answers
11k views

Why is 1 of my 24 CPUs Pegged at 100%?

I have an HP ProLiant DL380 G7 system using 2 6-core CPUs, with Hyper-threading enabled, for a total of 24 logical CPUs (as seen by Windows). When running our application, total system CPU ...
Patrick Cuff's user avatar
12 votes
2 answers
30k views

How can a Perfmon "% Processor Time" counter be over 100%?

The counter, Process(sqlservr)\% Processor Time, is hovering around 300% on one of my database servers. This counter reflects the percent of total time SQL Server spent running on CPU (user mode + ...
Bill Paetzke's user avatar
12 votes
4 answers
23k views

Is there a way to calculate the percentage CPU utilization by reading /proc/stat at once?

I guess the question is, could I somehow calculate the CPU utilization percentage just by reading the /proc/stat once? # head -1 /proc/stat cpu 67891300 39035 6949171 2849641614 118251644 365498 ...
Istvan's user avatar
  • 2,600
12 votes
11 answers
17k views

What creates CPU I/O wait but no disk operations?

I have CPU I/O wait steady around 50%, but when I run iostat 1 it shows little to no disk activity. What causes wait without iops? NOTE: There no NFS or FUSE filesystems here, but it is using Xen ...
Jason Cohen's user avatar
  • 1,127
12 votes
5 answers
68k views

TrustedInstaller.exe takes a lot of CPU

Does anyone know how to fix issue with TrustedInstaller.exe when it takes a lot of CPU? Operating system: Windows 2008 x64 Windows' Modules Installer service is set to Manual.
GrZeCh's user avatar
  • 605
12 votes
5 answers
12k views

IIS App Pool High CPU usage despite no requests

I have recently migrated a set of Windows Server 2008 R2 / IIS 7.5 servers to new servers running Windows Server 2012 / IIS 8. I am experiencing some odd behavior from IIS. We have 2 identical ...
Leland Richardson's user avatar
10 votes
3 answers
18k views

Why is my router CPU at 40% when no processes use more than 2%?

I have a problem, I have a Cisco 1841 running Cisco IOS 15, and I get strange behavior. The CPU usage is shown as 40%, but there is no processes that is using this much CPU power. Here is an example:...
Kedare's user avatar
  • 1,786
9 votes
1 answer
3k views

Do CPU credits exist for c5d.large instances? And if not, why not?

I've been paranoid that the websocket feed I was listening to on a t3.micro instance was being inhibited by cpu steal time from other instances under the same hypervisor. So I switched over to a c5d....
randy's user avatar
  • 101
9 votes
1 answer
17k views

CPU% more than 100 in ps -aux

We use ps -aux to find out when tomcat process takes high CPU utilization, if that so we will send a alert to Group. But some times %CPU shows more than 100, but our application working fine. Is it ...
Selvakumar P's user avatar
9 votes
2 answers
22k views

How to check gpu usages on aws ec2 gpu instance?

I'm running a ubuntu gpu instance on AWS ec2. I'm not sure if my application is using gpu accelerations. So how to check gpu usages on aws gpu instance?
aplrh's user avatar
  • 91
9 votes
1 answer
3k views

How to investigate the cause of a 100% CPU event that lasted for hours?

Yesterday the CPU on my Xen-based VPS server went to 100% for two hours and then went back to normal, seemingly naturally. I have checked logs including syslog, auth.log and more and nothing seems ...
thomasrutter's user avatar
  • 2,576
8 votes
3 answers
23k views

How can I monitor CPU usage and processes on Windows Server 2012 as a service over a 24 hour period?

We have a long running performant operation that runs for 6 hours. When it was last ran, something happened for 5 minutes where its performance dropped dramatically and caused a few timeouts, in the ...
NibblyPig's user avatar
  • 328
8 votes
1 answer
3k views

Very uneven CPU utilization with SQL Server 2012 on 2 processor computer with 16 cores / processor

After installing SQL Server Enterprise 2012 with the Server + Cal license model, on a computer with 2 processors each with 16 cores (and no hyperthreading involved) and putting the server under ...
cooplarsh's user avatar
8 votes
1 answer
315 views

Windows Servers on ESXi 100% CPU at year rollover

We have a number of Windows Server 2008 R2 SP1 servers running on ESXi servers. At year end rollover 2014 to 2015 the CPUs go to 100% and the machines hang. The solution appears to be a hotfix (...
Larry Hannah's user avatar
7 votes
4 answers
11k views

vCPU performance between 1 or 2 vCPU's

Within virtualisation (Predominantly VMware) is there a performance advantage using either 1 CPU with 4 cores or 2 CPU's with 2 cores? Let's assume the application running on a VM can use two CPU's.
esx_admin18's user avatar
7 votes
4 answers
11k views

Graphing per-user CPU usage on a Linux machine

I want to graph (graphical output would be great, i.e. a .png file) the following situation: I have users A, B, and C. I limit their resources so that when all users run a CPU intensive task at the ...
mart1n's user avatar
  • 173
7 votes
2 answers
9k views

CPU allocation for VMs on ESXi

I'm a complete VMware know-nothing, but I recently set up 4 VMs on ESXi. 3 of the VMs are very non-resource-intensive (a lightly used file server, a lightly used domain domain controller, and a VMware ...
Martin's user avatar
  • 73
7 votes
2 answers
5k views

Why do user and system cpu in cpuacct.stat not add up to cpuacct.usage?

Question relates to Linux cgroups cpu accounting. I noticed this at the container level, but it persists up to top level. For instance: # cat /sys/fs/cgroup/cpu/cpuacct.stat /sys/fs/cgroup/cpu/...
Bryan's user avatar
  • 354
7 votes
1 answer
850 views

Right way of measuring overlay network performance

I am currently examining the performance (especially UDP throughput) of different Docker overlay networks. I do this by creating point-to-point connections between two hosts that are connected with a ...
arne.z's user avatar
  • 357
6 votes
2 answers
2k views

How to compare mainframe CPU performance?

I am working with an application that runs on tomcat in OMVS. It run terribly on one mainframe, and adequately another another. Is there a way I can compare the CPU of the two mainframes as a ...
GC_'s user avatar
  • 211
6 votes
4 answers
42k views

Need help trouble shooting high CPU usage by PHP-fpm

There is a problem that is driving me crazy. After the day I tried to fix the CPU usage problem of my VPS, the CPU load has grown from 60% to 150%, and I have no idea what causes the problem. Please ...
yang's user avatar
  • 161
6 votes
4 answers
2k views

How is RAM and CPU allocated if no manual changes are applied to an Ubuntu Server

We have an Ubuntu Server (16.04) running R-Studio Server where we do statistical simulations. Those simulations are sometimes heavy on RAM and CPU so i would like to know how memory and RAM is ...
joaoal's user avatar
  • 173
6 votes
2 answers
2k views

cpufreq-info differs from /proc/cpuinfo?

I have a server and I want to ensure it's always running at maximum speed, never in energy-saving mode. I've tried a few strategies (aside from rebooting and changing the setting in the bios, which I ...
Evan's user avatar
  • 497
6 votes
1 answer
33k views

How to find what processes were running at a time in the past?

I am asked to investigate a high CPU usage alert which occurred this morning. I used sar -p and saw the high CPU usage showing up at that time Next I used ps -eo pcpu,pid,user,args | sort -r -k1 | ...
juniorbansal's user avatar
6 votes
3 answers
14k views

Intermittent high CPU (100%) on production webserver

X-Post from StackOverflow: https://stackoverflow.com/questions/9465123/intermittent-high-cpu-100-on-production-webserver We have a web cluster with 3 web-servers, each with 24 cores & 24GB mem. ...
Dave's user avatar
  • 161
6 votes
3 answers
3k views

When is sustained 100% CPU utilization not a worry?

Please help refine a discussion going on in our shop. Consider the following scenario. There is a Microsoft VPC running several apps and services (Windows 2003 server). The server has two or three ...
Eldergriffon's user avatar
6 votes
3 answers
5k views

CPU overloaded but no proccess is using more than 1% [duplicate]

I am monitoring a Cpanel (centos) server which have a 2-core CPU (4 virtual CPU cores) and it seems to be overloaded because I got this values using top: load average: 11.80, 13.30, 13.02 Cpu(s): 42....
Pablo's user avatar
  • 99
6 votes
5 answers
7k views

SQL Server suddenly using only a small portion of CPU

We've got a Windows 2008 R2 server running SQL Server 2008. All of a sudden, the SQLServer process is refusing to go above 20% CPU usage. As of last week, when running a heavy query against the db it ...
hermiod's user avatar
  • 183
6 votes
5 answers
11k views

CPU's on Hyper-V host system is just idling, even though VM's are at full throttle

I have a server that is running Windows 2008 64 bit Hyper-V, with 8 gigs of RAM and Intel Xeon X3440 @ 2.53 Ghz, which gives me 8 logical cores in the performance monitor on the host system. I have ...
Bjørn's user avatar
  • 337
6 votes
2 answers
7k views

Monitor and graph CPU usage per process and per thread

I need to monitor CPU usage by a given process and each of its threads. For each of them I want to have: average and maximum CPU usage percent, total CPU time used during the captured period, a graph ...
VladV's user avatar
  • 173

1
2 3 4 5
14