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Questions tagged [cpu-usage]

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

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4answers
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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?
33
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4answers
73k 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 ...
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4answers
20k 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 ...
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4answers
14k 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 ...
23
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2answers
6k 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 ...
22
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7answers
38k 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:...
21
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2answers
11k 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 ...
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3answers
21k 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 ...
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5answers
43k 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, ...
17
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7answers
4k 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 - ...
16
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1answer
106 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 ...
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3answers
17k 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 ...
14
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2answers
5k 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)
12
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4answers
6k 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 ...
12
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4answers
20k 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 ...
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11answers
12k 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 ...
12
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5answers
60k 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.
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4answers
6k 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 ...
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5answers
26k 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 ...
10
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5answers
9k 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 ...
9
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3answers
15k 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:...
9
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1answer
8k 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 ...
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5answers
54k 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 ...
8
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2answers
18k 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 + ...
8
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1answer
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 ...
8
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1answer
245 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 (...
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4answers
7k 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.
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4answers
9k 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 ...
7
votes
1answer
8k 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 ...
7
votes
1answer
412 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 ...
7
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0answers
2k 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 ...
6
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4answers
813 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 ...
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3answers
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 ...
6
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2answers
7k 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 ...
6
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3answers
2k 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....
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5answers
5k 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 ...
6
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1answer
3k views

Memcached keeps increasing cpu ussage

I'm running a memcached server which is serving two front end servers. These are connecting to the memcached server from Apache2/PHP using the standard PECL library. For some reason the memcached on ...
5
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2answers
806 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 ...
5
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3answers
11k 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. ...
5
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2answers
1k 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 ...
5
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4answers
13k 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 ...
5
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2answers
6k 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 ...
5
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4answers
14k views

How can I investigate sustained high CPU usage by Microsoft.Exchange.Rpc.ClientAccess.Service.exe?

One CAS server in our array has nearly 90% of its 4 CPUs used. The remaining CAS servers are at 30 percent. How should I investigate what is causing this increase? Below is a graph of: Six (6) ...
5
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1answer
7k views

Erratic CPU usage by mscorsvw.exe (.NET Runtime Optimisation Service)

I have a Server 2008 R2 Terminal Server that's just been kinda sitting around for the last three months with very, very low usage (perhaps 1 user for an hour, once a day). All of a sudden, for no ...
5
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5answers
9k 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 ...
5
votes
1answer
2k 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 ...
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4answers
2k views

Random high CPU usage on Linux using Apache

I've recently had a bit of a strange problem with my web server. Over the last day or so the site seems to be slowing down somewhat at random intervals, we don't seem to be experiencing any major ...
5
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4answers
4k views

Does WMI cause CPU Creep?

I have a few servers, running Server 2003 Std/Ent and SQL 2000/2005, that I've noticed will start showing higher CPU usages over time. Stopping the WMI service and restarting it will always bring it ...
5
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1answer
590 views

Artificially Generate CPU Steal

Anyone know of a good way to artificially generate CPU steal? I have some automation I want to test which is triggered by CPU Steal, but for the life of me I can't figure out how to force CPU Steal ...
5
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4answers
11k views

100% CPU when doing 4 or more concurrent requests with Magento

Currently I'm having trouble with a server running Magento, it's unbelievably slow. It's a VPS with a few Magento installations on it used for development, so I'm the only one using them. When I do 4 ...