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31

On a CPU utilization graph or report, the "nice" CPU percentage is the % of CPU time occupied by user level processes with a positive nice value (lower scheduling priority -- see man nice for details). Basically it's CPU time that's currently "in use", but if a normal (nice value 0) or high-priority (negative nice value) process comes along those programs ...


25

CPU time is allocated in discrete time slices (ticks). For a certain number of time slices, the cpu is busy, other times it is not (which is represented by the idle process). In the picture below the CPU is busy for 6 of the 10 CPU slices. 6/10 = .60 = 60% of busy time (and there would therefore be 40% idle time). A percentage is defined as "a number or ...


23

Edit: Updating on Oct. 1 2013 - Some of my original answer has since become obsolete. I'm not sure if you're still active on this site or that you'll see this, but I wanted you to know that I read this question today and it fascinated me, and so I spent all day (when I should have been working) researching Hyper-V and Windows internals and even digging in ...


22

Show the "CPU Time" column on the "Details" tab in "Task Manager" and look for a process with a CPU time count that's steadily increasing. That's your wedged process. It should be using around 4.17% CPU constantly.


16

TL;DR: EventLog file was full. Overwriting entries is expensive and/or not implemented very well in Windows Server 2008. At @pk. and @joeqwerty suggestion and after asking around, I decided that it seemed most likely that a forgotten monitoring implementation was scraping the event logs. I installed Microsoft's Network Monitor on one of the Domain ...


14

There are a couple of possible ways you can do this. Note that its entirely possible its many processes in a runaway scenario causing this, not just one. The first way is to setup pidstat to run in the background and produce data. pidstat -u 600 >/var/log/pidstats.log & disown $! This will give you a quite detailed outlook of the running of the ...


13

It is the CPU scheduling priority, higher vales (+19) mean lower priority, and lower values (-20) mean higher priority (inverse relationship). man 2 getpriority will give you lots of details. You can set the nice value when launching a process with the nice command and then change it with the renice command. Only the superuser (root) can specify a priority ...


11

Try monit. You could use a configuration like this, to accomplish your task: check process gameserver with pidfile /var/run/gameserver.pid start program = "/etc/init.d/gameserver start" with timeout 60 seconds stop program = "/etc/init.d/gameserver stop" if cpu > 80% for 2 cycles then alert if cpu > 95% for 5 cycles then restart if ...


10

The Steal percentage (documented in the mpstat man-page) is indeed the hypervisor telling your VM that it can't have CPU resources the VM would otherwise use. This percentage is regulated in part by Amazon's CPU limiting, and VM load on that specific host. I/O load is monitored through the %io stat.


10

CPU utilization is measured relative to a single CPU. The maximum is 100% for each CPU, so a four-CPU system would have a maximum CPU utilization of 400%.


10

The CPU time is the time that the process is using the CPU - converting it to a percentage is done by dividing by the amount of real time that's passed. So, if I have a process that uses 1 second of CPU time over a period of 2 seconds, it's using 50% of a CPU. In the case of your MATLAB process, 217% indicates that it's used 2.17 seconds of CPU time per ...


9

It seems to be all Kernel time, could be Interrupts, they might only get handled by a single CPU.


9

As others have already pointed out, we can see from that screenshot that the CPU that's working so hard is spending all its time in kernel mode. (The red color.) Running Powershell as administrator, type: Get-Process | Select Name, PrivilegedProcessorTime | ` Sort-Object PrivilegedProcessorTime -Descending The process at the top of the list is the ...


9

How many cores do you have on this server? 106% means it's occupying a full core plus a little of another. So, if you have say, 4 cores, a process that is multi-threaded (so it can handle pushing load to all cores) could reach 400%. top will confirm this behavior.


8

You are on the right track, top uses this file for this purpose. But you need to read it more than once. Utilization is a is a measure of use over time. You can read it once providing you know the uptime in seconds of the host, then divide by that, but that would give you a utility rate of the host since the machine was booted. If you want a rate over 5 ...


8

/usr/bin/php is the PHP binary (php "parser", the "thing" that runs your php code), which is running a script: /home/hellohel/public_html/index.php. I would check that script, to see what's causing it to use up that much resources.


8

Have you looked at the Cisco troubleshooting guide for high cpu ? It has an extensive guide on what to do when encountering high CPU loads. Included are : Determining Causes and Solving the Problem : High CPU Utilization due to Interrupts High CPU when Enabling Netflow NDE on Cisco 7600 Series Router High CPU Utilization due to Processes PCI and FAST ...


8

CPUs (or individual cores) can be put into "deep" C-states by an OS kernel. You're thinking that the processor "puts itself to sleep" when it "detects" inactivity. This isn't how it works. The OS scheduler determines system idle percentage based on the amount of time spent in the system idle loop to detect system inactivity. The CPU itself (in x86 land, at ...


8

Not considerable enough to make an impact. The adjustments are more for licensing. For example, Windows Server is licensed per processor slot, so you'd pay more to have 1 core and 4 CPUs than to have 1 CPU and 4 cores. Same goes with other products whose costs quickly rise with more processors (looking at you, Oracle).


7

In general, I've seen this happen because of a stalled-read. This is confirmed by your strace output. The attempt to read /proc/xxxx/cmdline file hangs while you're running ps aux command. The momentary spikes in I/O are starving the system's resources. A load of 90-160 is extremely bad news if it's storage subsystem-related. For the storage array, can you ...


7

One thing to try: router(config)#no logging console no logging console will disable the output of the debug message on the serial console. As the console is interrupt-driven, each character is an interrupt.


7

One of the canonical sources for ESX performance tips is the Performance Troubleshooting Guide! (PDF) In short: If your host is busy, and your VMs are reporting a high "ready-time," (which is a counter of when the VM is ready to perform work but no physical CPU can be found for the machine to be scheduled by the hypervisor) then the symptoms you are ...


7

beware that, in the case of EC2, top is not a reliable tool to measure CPU usage. See more info at http://www.axibase.com/cloud/2010/07/22/ec2-monitoring-the-case-of-stolen-cpu/


7

There are two counters with the same name: Process\% Processor Time: The sum of processor time on each processor Processor(_Total)\% Processor Time: The total for all processors Your question indicates you're using the first counter, which means that its maximum value is 100% * (no of CPUs). So if you have 4 CPUs, then the total maximum is 400%, and 80% ...


7

You might be I/O or memory limited, rather than cpu limited. Your cpu won't burn cycles just to burn cycles if it's stuck waiting on disk, network, or memory. It could also be a software limitation, if you're using something that's not written to be aware of more than 24 cores.


7

mscorsvw is a process that pre-compiles .NET binaries. Your updates may have triggered this activity. At least, that's what http://blogs.msdn.com/b/davidnotario/archive/2005/04/27/412838.aspx says is happening. You might get more clue what exactly is happening if you can run the sysinternals procmon utility. That will tell you what file(s) mscorsvw is ...


7

FreeBSD has a pretty decent userbase of very knowledgeable people. I wouldn't worry about that too much. Bigger issue would be your personal experience and knowledge on the matter. Ask yourself (and tell us): why is it so important to have a couple of megs of extra free RAM in your server? What does that gain you? And what does it cost you, both in terms of ...


7

In cases like this, you need to go beyond task manager and looking at % CPU usage. That does not tell you if something is adversely affecting performance. For a case like this, the next step would be to use Performance Monitor to view System\Processor Queue Length. This tells you if processes are waiting for the CPU to become idle possibly affecting ...


6

The key issue is "how much data is being compressed?". If you are running a massive DB query that takes a noticeable number of seconds to run, and the resulting page is a few tens of Kb long, then the expense of compressing the data will be completely dwarfed by the expense of the SQL work to the point where there is no point even thinking about it. A ...


6

Windows Server 2008 will run TrustedInstaller.exe shortly after rebooting after installing the monthly Windows Updates. The program will take up ~75-100% of a CPU core for up to ~30 minutes, as it is running the malicious software removal scanning code. While this is running on a single-core machine, certain programs or services will not work properly, ...



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