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30 votes
Accepted

stress-ng: Simulate specific cpu percentages

I designed stress-ng so that one can specify 0 for the number of stressor processes to match the number of on-line CPUs, so to load each cpu at say 40%, use stress-ng -c 0 -l 40
Colin Ian King's user avatar
25 votes
Accepted

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

CPU credits only apply to T2/T3 instances. Each T2/T3 instance accumulates some CPU credits per second and also when it's in use (i.e. not "idle") it spends these CPU credits. When it runs out of ...
MLu's user avatar
  • 25.5k
24 votes
Accepted

Use of CPUQuota in systemd

The Good Your solution is the correct and should actually be quite future-proof; by using systemd to control the services cgroup settings, eg. CPUQota. [Unit] Description=Virtual Distributed Ethernet ...
TomKeegasi's user avatar
11 votes
Accepted

Why is my AWS instances suddenly becoming irresponsive reporting high "stolen" CPU

The t-series of instances at Amazon use a quota system for CPU usage. When you reach your quota, you start seeing your stolen percentages rise. There isn't much you can do about that, it's structural ...
sysadmin1138's user avatar
  • 134k
9 votes

How to compare mainframe CPU performance?

Kevin mentions a number of great points, but it might help to start the analysis at a little higher level: what are the two machines and, since we're talking about Tomcat which runs in a JVM, do both ...
randomScott's user avatar
9 votes

How to compare mainframe CPU performance?

Comparing the number of CPUs of a mainframe image isn't meaningful, most likely. Mainframes are designed to run multiple tasks at the same time, and give priority to whatever the business says is ...
Kevin McKenzie's user avatar
9 votes

Windows File server heavy cpu usage - Render Farm with many clients reading data at once

A few things to note, that 40Gbps NIC is only connected to one socket/NUMA-node - so if it's associated with the second socket then any file-sharing workload handled by the first socket will have to ...
Chopper3's user avatar
  • 102k
8 votes
Accepted

PHP-FPM using 100% CPU on a server that has 16 threads

I would use php-fpm settings with pm = static. From my experience high traffic websites work better with pm static rather than dynamic/ondemand. You can get an ideea about the memory used by a php-fpm ...
Bogdan Stoica's user avatar
7 votes

CPU load for high performance computing

Load average shows the queue of threads ready to run. In Linux, this includes also threads waiting for disk. It could happen that a broken NFS server could increase the load average to insane numbers. ...
Mircea Vutcovici's user avatar
7 votes
Accepted

ZFS: arc_prune is using 100% CPU with high load average

Something is forcing ZFS to reclaim memory by shrinking ARC. To immediately solve this problem, you can try issuing echo 1 > /proc/sys/vm/drop_caches to drop Linux pagecache only, or echo 3 > /...
shodanshok's user avatar
7 votes

Load average greater than number of CPUs

Linux load average is a number equal to the number of the running processes plus a number of processes ready to run and waiting for available CPU plus the number of processes in uninterruptible state (...
AlexD's user avatar
  • 10.4k
6 votes
Accepted

High CPU Load on Synology by smbd

First, this seems a common problem with DS213j and DSM 5.1+. Someone reported that after a reboot, the problem went away: have you tried it? From your top data, it seems that the CPU is busy with ...
shodanshok's user avatar
6 votes

How to check gpu usages on aws ec2 gpu instance?

Use: nvidia-smi -h to see the options. Display info arguments: Display only selected information: MEMORY, UTILIZATION, ECC, TEMPERATURE, POWER, CLOCK, ...
Tung Le's user avatar
  • 61
6 votes

stress-ng: Simulate specific cpu percentages

I should have used -l option Looks like -c 1 distribute the load between all cores. Not exactly 80/4 per core, I guess because the host already runing some stuff. stress-ng -c 1 -l 80 and -c 4 ...
AJN's user avatar
  • 456
6 votes

Root user consume huge amount of CPU

If your company has a breach response process, I would invoke that now. Otherwise: This looks potentially malicious, I would recommend looking at it closer in /proc. With a root privilege shell, ...
virullius's user avatar
  • 1,058
6 votes

AWS server completely shutting down because of the insufficient CPU memory (server-kernel: out-of-memory )

What may be causing the problems with the CPU usage Bad configuration. First you need to reduce the memory overcommit (the default heuristic is way too optimistic on server hosts). There is lots of ...
symcbean's user avatar
  • 22.6k
5 votes
Accepted

virsh vcpu_period and vcpu_quota

quota The optional quota element specifies the maximum allowed bandwidth(unit: microseconds). A domain with quota as any negative value indicates that the domain has infinite bandwidth, which means ...
livelace's user avatar
5 votes

High CPU Load on Synology by smbd

I had also the same problem with : random slow load problem when I navigate into folder with Windows Explorer hight CPU usage by the smbd process (~50%) when the random problem that talk about ...
Florent Poittevin's user avatar
5 votes
Accepted

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

RAM is first-come-first-serve. If userA runs 9 processes that allocate 10% of memory each, and then userB logs on, userB will see only 10% of memory left. In the event that memory is exhausted, ...
Ben Scott's user avatar
  • 380
5 votes

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

If you need to limit memory usage on the same server, your best bet will be to either Use two Virtual Machines, ideally KVM so that you can use the existing Ubuntu server to host the VMs. However, ...
zymhan's user avatar
  • 1,382
5 votes
Accepted

50% Load on 2 CPU is the same that 100% Load on One CPU?

It's not quite that simple. With one thread or process that burns as much CPU as possible, it will max out at 50% CPU on a dual CPU system. Or, some systems will show it as 100% CPU, because the ...
Halfgaar's user avatar
  • 8,214
5 votes

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

Windows Server has a built-in tool to show performance data in real time or to collect data in logs for later review. I think that this will do exactly what you are looking for. See this article for ...
Daniel K's user avatar
  • 675
5 votes
Accepted

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

Using Daniel K's suggestion of performance monitor, I found out how to do this. Load up Performance Monitor Go to 'Data Collector Sets' Expand 'User Defined' Make a new 'Data Set' Select Create ...
NibblyPig's user avatar
  • 328
5 votes

Can I have multiple threads running in parallel in a pod with a CPU limit set to 500 millicores?

You certainly can run 2 threads in a container at once using 25% of the cputime each. However, as for whether these will be run exactly together, I'm not 100% sure. Running the following tests do seem ...
Marco's user avatar
  • 307
5 votes

Running a cluster 24x7 at full load. Possible damages?

how long will it be able to sustain without any physical damage? If you buy decent production-quality servers then no, you shouldn't see any damage. In fact there's an argument that you'd see less ...
Chopper3's user avatar
  • 102k
4 votes
Accepted

How can I keep a third-party cloud provider accountable for guest VM performance?

It's perfectly possible; pretty much anything can be specified in a Service Level Agreement (SLA). Since your provider is a smaller one, I would say you have a somewhat better chance of getting this ...
MadHatter's user avatar
  • 80.8k
4 votes

High load average, when should I be worried?

Only worry if it actually corresponds to a slow application. A bit more precisely, load average relates to the number of processes running or waiting. This can be a lot more than 1 and perform just ...
John Mahowald's user avatar
4 votes

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

I'm not a kernel developer, but, digging through the kernel source code, cpuacct.usage (updated via cgroup_account_cputime) and cpuacct.stat (updated via cgroup_account_cputime_field seem to be ...
user690623's user avatar
4 votes
Accepted

Does AWS charge for CPU Usage?

AWS gives you control over this. Typically the T instance have a hard limit on the CPU allowed, with no additional costs. The new T2 / T3 unlimited capability lets you use more CPU and get charged for ...
Tim's user avatar
  • 33k
4 votes

What is the relation between IO wait utilisation and load average

(Assuming Linux, although the general concept can be applied to other operating systems.) A workload cannot be described only by the load average and %iowait. Those are metrics that only summarize ...
John Mahowald's user avatar

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