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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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1answer
1k views

How is load average related to CPU utilization?

I am facing a load average of > 3 since past 2 days. The CPU utilization is never above 40 % in all cases. Here are some screenshots of Server Density monitoring tool that I use. The process snapshot ...
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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 ...
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 ...
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 ...
15
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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 ...
20
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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 ...
7
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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 ...
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 ...
3
votes
3answers
535 views

Is the system load tied directly to CPU usage?

It's a dual-core machine and the load is around 24 but CPU usage is bouncing around from 60-80% and never reaching 100% so how can there be that many processes waiting? I/O is pretty much nill since ...
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:...
38
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4answers
77k 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?
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4answers
13k 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 ...
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 - ...
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 + ...
5
votes
2answers
6k 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 ...
5
votes
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 ...
7
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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.
5
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2answers
906 views

Uneven CPU core utilization

tl;dr: First CPU core is consistently saturated, all other cores are consistently under-loaded. A VM, inside Ubuntu-based Xen XCP: $ uname -a Linux MYHOST 2.6.38-15-virtual #59-Ubuntu SMP Fri Apr 27 ...
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2answers
1k views

Can an ESX server under heavy load cause cpu spikes on guest VM's?

So we have a number of vm's running on an ESX 4.1 server for product testing. The ESX Server is at times under heavy load. We've been experiencing high CPU levels during some use cases, but we can't ...
3
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2answers
6k views

Why does mpstat show different values when I use the interval setting?

Here's the output I get when I run mpstat: $mpstat Linux 3.2.0-30-generic (my-laptop-C650) 09/17/2012 _x86_64_ (2 CPU) 05:32:01 PM CPU %usr %nice %sys %iowait %irq %soft %...
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3answers
3k views

IIS w3wp using high cpu with no traffic

I am seeing the following suspicious behavior on one of our web servers (IIS 6.0 on win2k3). two CPUs hyperthreaded into 4. In task manager and perfmon the w3wp.exe's cpu utilization does appear to ...
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2answers
1k views

Dual Quad Core Xeon CPU but still high load

I have a dedicated server with following specs: Two Intel Xeon-Harpertown 5430-Quadcore[2.66 Ghz] 4GB DDRII RAM 500GB SATAII HD CentOS 5.5 64-bit Problem is that even with such specs MySQL still ...
3
votes
2answers
9k views

CPU load too high. How to investigate?

This is my "top" screen. Now it's 2.96. Sometimes it goes above 3! I've read that it's not good. How to investigate and fix it?
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4answers
2k views

Hyper-V CPU Utilization, Good Tools? [closed]

I just learned a ton from this post: Host CPU% doesn't include child VM CPU%, specifically I learned that both the 'host OS' and 'child VM' are siblings within the HyperVisor layer. Are there good ...
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)
3
votes
1answer
7k views

Disabling CPU management

If I add the following processor.max_cstate=0 to the kernel command line for boot up, does that disable all CPU power management and throttling? I also found: http://www.experts-exchange.com/OS/Linux/...
2
votes
3answers
948 views

Apache2 return 404 for proxy requests before reaching WSGI

I have a Django app running under Apache2 and mod_wsgi and, unfortunately, lots of requests trying to use the server as a proxy. The server is responding OK with 404 errors but the errors are ...
2
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2answers
3k views

XenServer 6.2 VM 100% CPU and 100% memory usage and won't boot

I had this problem today after a power failure. I had 2 vms and one of them won't boot and was using 100% of CPU and 100% of memory. Since it was very dificult to solve (at least for me) I want to ...
1
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1answer
68 views

Why does my VM become slower during CPU-heavy tasks after some days of runtime?

I'm dealing with some strange problem for some time now: After some days of runtime, one of my VMs seems to become slower on CPU-heavy tasks. One example were this happens is reading virus signature ...
1
vote
1answer
3k views

Linux Load Averages and HyperThreads

My rough understanding of a Linux load Average is that for every integer a CPU core is working all the time. For example, 1 means on a 4 core system that 1 core is working at capacity. How does ...
0
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1answer
869 views

Munin: Graph not plotting one label

I have set up munin to monitor EC2 instances. Now my CPU usage graph (using the unmodified cpu plugin) looks like this: The problem is that the "iowait" parameter is returned correctly (see text ...
0
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1answer
7k views

Kill w3wp.exe if it is working on 100% cpu over a period of time

Im running a ASP.NET website on Windows 2008 and IIS7. From time to time my w3wp.exe start spiking into 100% CPU, and the website hangs. I have not found the reason for this, but that is irrelevant ...
0
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1answer
313 views

How does a power graph of a server running a job look like when there is no CPU power management mechanism deployed

Suppose there is no CPU power management mechanism deployed in a server, and i run a job on it and monitoring the power drawn by the server by using a wall power meter, what kind of a profile do you ...
0
votes
1answer
603 views

Apache/Passenger and cpulimit

I run a ruby on rails site that processes email - the email is dumped directly into the web app via a POST from postfix. At times I can get a burst of email coming in causing a prolonged surge in ...