CPU is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer.

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is there anyway to know if your supposedly fully dedicated server is really a virtually resource-shared machine? [duplicate]

sometimes I feel my server not responding as smoothly as I would expect (i have a Intel(R) Xeon(TM) CPU 2.80GHz Quad Core), given that for example, the 'top' commands reports a low load < 0.5, CPU ...
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Is it possible to limit a Linux process so that it can only run on a particular core on a particular machine?

Let's say I have a quad-core box and four identical processes, each with ten threads. Is it possible, in Linux, to say that Process A is only allowed to run on CPU 0, Process B is only allowed to run ...
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Disable CPU cores in bios?

Is it possible to disable CPU (Intel) cores in BIOS, and if yes what HP/DELL (others?) 1U/2U servers would allow this? It is becoming difficult to find new server hardware with dual core CPUs, most ...
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443 views

Measuring load - %CPU in top is different than %us

When I run TOP on a remote server, I see a very small system utilization (3.8%us). However, for the actual process I am seeing 29.6% of the CPU. Since this server has 8 CPU cores, is the %CPU the ...
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Is it possible to influence the way CPUs are enumerated under Linux?

I have a HP DL380 G7 with 2 mismatched CPUs in it. One is a quad core CPU with faster cores, and one is a 6 core CPU with slower cores. On this box I run an application that due to licensing reasons ...
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Virtualized CPU cores vs. threads

We've got a KVM host system on Ubuntu 9.10 with a newer Quad-core Xeon CPU with hyperthreading. As detailed on Intel's product page, the processor has 4 cores but 8 threads. /proc/cpuinfo and htop ...
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VMware lockup CPU spike

After a CPU usage spike, the host server for VMWare ESXi 5.5 became unresponsive regarding the DRAC, Network, and cluster membership. The host is a blade module is Dell PowerEdge M820 in a Dell ...
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Selecting a webserver configuration

I have a website, which has grown from 10 visits per day, to 100 per day in couple of months, and now to about 800 unique visits per day. So far, I have been using a VPS with 512MB RAM, and shared ...
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Getting CPU information from command line in Mac OS X [server]

Sometimes I need to gather information about the client's server prior to making real work there, i.e. getting info on CPU type and activity. On Linux there is mpstat and /proc/cpuinfo, both of them ...
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Disable CPU Scaling in Windows Server 2008 R2

How do you disable CPU power management scaling in Windows Server 2008 R2? After setting the Control Panel, Power Management plan to performance and then rebooting -- CPUID's Cpu-Z still shows the ...
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Does CPU power management affect server performance?

I was doing some simple hand benchmarking on our (live) database server during non-peak hours, and I noticed that queries returned somewhat erratic benchmark results. I had enabled the "Balanced" ...
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Monitoring/controlling Intel Turbo Boost in Linux

Is there a nice way to monitor and/or control Intel Turbo Boost technology on Nehalem processors from a Linux host? I'm looking to do this RHEL/CentOS 5.5 hosts running stock or Realtime MRG kernels. ...
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KVM: Which CPU features make VMs run better?

We are using Ubuntu 12.04 with the following parameters: Dell R910 Kernel 3.2.0-25-generic #40-Ubuntu SMP x86_64 x86_64 x86_64 GNU/Linux kvm 1:84+dfsg-0ubuntu16+1.0+noroms+0ubuntu13 qemu-kvm ...
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3answers
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“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 ...
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Confused by CPU values in Unix 'top' command

In the screenshot below, the overall CPU is being reported as 3% but the mysqld process is reported as using 57%. Is this 57% of the overall 3% and thus mysqld is only using about 1.5% of the CPU? ...
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1answer
991 views

KVM/Qemu, Ubuntu: Why do more guests CPUs enhance Disk-I/O rapidly?

We have an Heartbeat/DRBD/Pacemaker/KVM/Qemu/libvirt cluster consisting of two nodes. Each node runs Ubuntu 12.04 64 Bit with the following packages/versions: Kernel 3.2.0-32-generic #51-Ubuntu SMP ...
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VMware Host CPU Usage Climbing

This is somewhat of a longshot, but I am wondering if anyone might be able to explain the following: I have a VMware Host Server running Ubuntu Server 8.04 LTS, and VMware Server 2.0. The User CPU ...
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Why is CPU use so asymmetric on our 8-cpu SQL Server box?

I've noticed that the CPU usage on our 8-CPU database server, running SQL Server 2008, is not balanced at all. Here are the 1 day averages for a random day a while back, which is typical and ...
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How do I log CPU usage per process?

I have a box on Linode that's going through weird behavior. Every now and then CPU and disk I/O will shoot to 100% and the server becomes unresponsive and has to be booted. I'd like to investigate ...
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1answer
182 views

Can I mix two cpus with a different clock speed on a board?

I have received an old server which has a xeon E5405 (2GHz) processor. I'd like to buy and add a more powerful cpu (something like Xeon X5492) which has a higher clock speed but the same LGA 771 ...
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2answers
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KVM and virtual to physical CPU mapping

I'm a relative late comer to the virtualistion party, so you'll have to forgive me if this seems like an obvious question. If I have a server with 12 cores available, does each KVM guest have access ...
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Output of /proc/cpuinfo, 2 entries for each core?

Please help me understand the output of /proc/cpuinfo. My new server has dual quad cores. /proc/cpuinfo has two entries for each core (a total of 16 entries): processor : 9 vendor_id : ...
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Amazon EC2 micro instance has 100% CPU usage

My Amazon EC2 micro instance has 100% CPU usage very often. I only have a wordpress installation on it. I'm still in production mode, so no users but I get 100% CPU usage. Does someone know how to ...
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CPU/RAM upgrade for HP Proliant ML350 G5

I have an HP ML350 G5 server with a single Intel 5130 dual core Xeon installed. Is it possible to upgrade it to a dual processor system? I've looked at the quickspecs and spent a couple of hours ...
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1answer
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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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1answer
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top, w, ps showing wrong CPU times

I've spotted this trait recently on some of my Ubuntu servers (10.04.2) on Amazon EC2 (not noticed this on any physical boxes), and can't quite comprehend how it's getting these figures. They can't be ...
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5answers
789 views

%CPU for a process

Looking at the output of top on our server, one of my colleagues told me that the fact that some processes got less than 100 "%CPU" was because I was running too many processes. He added that based on ...
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2answers
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How to Monitor Windows Hosts Network Bandwidth through SNMP?

I need to monitor Linux and Windows hosts with SNMP and Cacti. I am looking for results in a graph format like MRTG. I'm looking for the following on the Windows Hosts: Disk Utilization, CPU load, ...
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1answer
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cat /proc/cpuinfo shows 3.00GHz model but 1400.000 cpu MHz?

I ran this command on ssh to see CPU info: cat /proc/cpuinfo And it says: ... vendor_id : GenuineIntel cpu family : 15 model : 4 model name : Intel(R) Pentium(R) 4 CPU ...
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1answer
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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: ...
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CPU?: Not responding

I'm attempting to build a system for co-location. I've been running into issues while trying to install CentOS 6.3 System Specs: Motherboard: ASUS m5a99x Process: AMD FX-8120 (8-core Bulldozer) ...
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1answer
162 views

Why do server vendors always ship them with disabled hardware virtualization support? [duplicate]

Possible Duplicate: Enabling hardware virtualisation BIOS; anything to beware? This, which seem to be common practice for all hardware vendors, has been bugging me for a while: why is ...
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3answers
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Diagnosing high CPU waiting

I have a monitoring server that is running icinga/collectd/graphite with about 50 hosts. I have noticed high load/slugging performance on the box. If you take a look at top, you'll see: Cpu(s): ...
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1answer
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High CPU utilisation w3wp.exe - GC issue?

I've inherited a website that uses a lot of session state. We've recently experienced continuous high CPU ~95-100% for prolonged period of times. When debugging using DebugDiag, it shows that there ...
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1answer
210 views

difference between taskset and cpuset

I'm trying to reduce the latency of my linux network application. I've learned that there are two tools for "binding" a program to particular CPU core: taskset and cpuset. Which one should I prefer? ...
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1answer
713 views

High CPU% stolen on EC2 instance at extremely regular intervals

I have a m1.small EC2 instance on AWS running some websites. I noticed my CPU usage have peaks at regular interval of times, exactly every 30 minutes (0:06, 0:36, 1:06, ...). I've checked my crons (I ...
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2answers
238 views

Is the # of CPUs on a virtual machine always meaningful?

On a virtual machine, if cat /proc/cpuinfo tells me that there are 4 CPUs, is this just as meaningful as if it were bare metal? Should I configure my server (for example, # of Nginx or Apache workers) ...
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What bus size does the armadaxp CPU with armv7l architecture of a Synology DS214 have?

less /proc/cpuinfo prints Processor : Marvell PJ4Bv7 Processor rev 2 (v7l) processor : 0 BogoMIPS : 1064.96 processor : 1 BogoMIPS : 1064.96 Features : swp ...
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2answers
298 views

HP ML150 G6 upgrading RAM/CPU beyond specs?

I am being told that some limits on some HP servers can be crossed. Do any of you have any experience with that? A ML150/G6 is limited to 48GB RAM but I have been talking to a German company that ...
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0answers
54 views

High load cause? [duplicate]

Possible Duplicate: what is my server high load cause (4 cores and 8 thread cpu) What is my high load cause? CPU,RAM or IO? 4 Core, 8 thread cpu top - 22:27:07 up 149 days, 5:26, 1 ...