I have 6 virtual machine when i am running kmeans workload.
And i extract the trace of the storage's characteristics (CPU ID, Device number, PID, Number of sector) by blktrace while i was running kmeans workload.
I want to know each VM request's characteristics by the trace of blktrace
So, i think that i should match (1VM - 1CPU) or know which CPU is allocated to VM.
Openstack documentation said that use vcpu-pinning or numa but i think it's such a complex thing.
Can I specify only certain cpu that are not shared by one VM?
Or is there a way to check the VM's request with cpuid or pid?
I want to know each VM request's characteristics by the trace of blktrace
So, i think that i should match (1VM - 1CPU) or know which CPU is allocated to VM.
Related
I want to get CPU usage (cumulative) for each VM hosted on a VMware ESXI host.
I tried using Power CLI command 'Get-VMHost' but it only gives the overall CPU usage by ESXI host.
For CPU usage esxtop is a very powerful ESX command and you have to run it at the CLI. I haven't used the Power CLI so I'm unsure if it's available there but it is definitely available at the CLI which VMware tries to discourage you from using (see https://kb.vmware.com/s/article/2004746). Documentation for esxtop for the latest release of vSphere is at https://docs.vmware.com/en/VMware-vSphere/7.0/com.vmware.vsphere.monitoring.doc/GUID-D89E8267-C74A-496F-B58E-19672CAB5A53.html.
That document is a bit terse and in terms of getting CPU usage for each VM this old documentation for esxtop may guide you a bit better https://www.vmware.com/pdf/esx2_using_esxtop.pdf. In particular note the different nomenclature of ESXi (and ESX) for which the primary unit of address space and execution is the "world" rather than the "process". Thus you want to get the CPU usage for all "worlds" associated with each VM. Some VMs may have only a single "world" and some may have several and it is configurable. As for esxtop, it has been around forever and most likely it can still today provide the same functionality that it did over a decade ago with ESX 2.
I am running Apache Guacamole on a Google Cloud Compute Engine f1-micro with CentOS 7 because it is free.
Guacamole runs fine for some time (an hour or so) then unexpectantly crashes. I get the ERR_CONNECTION_REFUSED error in Chrome and when running htop I can see that all of the tomcat processes have stopped. To get it running again I just have to restart tomcat.
I have a message saying "Instance "guac" is overutilized. Consider switching to the machine type: g1-small (1 vCPU, 1.7 GB memory)" in the compute engine console.
I have tried limiting the memory allocation to tomcat, but that didn't seem to work.
Any suggestions?
I think the reason for the ERR_CONNECTION_REFUSED is likely due to the VM instance falling short on resources and in order to keep the OS up, process manager shuts down some processes. SSH is one of those processes, and once you reboot the vm, resource will resume operation in full.
As per the "over-utilization" notification recommending g1-small (1 vCPU, 1.7 GB memory)", please note that, f1-micro is a shared-core micro machine type with 0.2 vCPU, 0.60 GB of memory, backed by a shared physical core and is only ideal for running smaller non-resource intensive applications..
Depending on your Tomcat configuration, also note that:
Connecting to a database is an intensive process.
Creating a Tomcat with Google Marketplace, the default VM setting is "VM instance: 1 vCPU + 3.75 GB memory (n1-standard-1) so upgrading to machine type: g1-small (1 vCPU, 1.7 GB memory) so should ideal in your case.
Why was g1 small machine type recommended. Please note that Compute Engine uses the same CPU utilization numbers reported on the Compute Engine dashboard to determine what recommendations to make. These numbers are based on the average utilization of your instances over 60-seconds intervals, so they do not capture short CPU usage spikes.
So, applications with short usage spikes might need to run on a larger machine type than the one recommended by Google, to accommodate these spikes"
In summary my suggestion would be to upgrade as recommended. Also note that, the rightsizing gives warnings when VM is underutilized or overutilized and in this case, it is recommending to increase your VM size due to overutilization and keep in mind that this is only a recommendation based on the available data.
Am starting to learn openstack. As per my understanding (after reading all the docs) is that the compute nodes run a host OS (ubuntu or other linux) and on top of that you have your hypervisor (like KVM) and then the VMs run on top of it i.e HW -> OS -> Hypervisor -> VMs . This is similar to having a VM running on Virtualbox which runs on a host operating system i.e HW-> Host OS ->VBox -> VMs.Please correct me if my understanding is incorrect.
Assuming my first understanding is correct, How will the performance of the VMs on the this architecture be compared to running the VMs directly on hypervisor i.e HW-> Hypervisor (KVM)->VMs ?
Comparing this with VMWare openstack architecture where Nova speaking to VMWare vCenter and then vCenter manages the ESXi nodes (vCenter and ESXi are on different nodes). This way my VMs are directly running on top of hypervisor connected to HW (HW->ESXi->VMs).And all the overlay networking is handled by NSX. This looks much more performant compared to the other architecture. Am i missing something here ?
Thanks in advance.
~exp8
Since kvm runs on linux kernel, and runs instructions directly on the cpu, it is the hypervisor (HW -> HyperVisor -> VM). On the VMware side, there is a tiny proprietary tuned version of linux as hypervisor.
To find out which one is more efficient, you should do benchmarking. But if you think Vmware's linux consumes less resources (less process, memory, cpu), it may be better.
Suppose in my pc I have Ubuntu as Host OS. Now I installed a Virtual Machine say VirtualBox (hypervisor) and then deployed a centos and a redhat os inside that as guest OS.
Suppose CentOS and redhat has 2 processes running and Ubuntu is running 3 processes. So following are my questions:
There are how many processes that Ubuntu is having?
Is there any difference between GuestOS and HostOS processes?
If all guestos runs as a process then they will get less time as compared to other process running on host os.
Please clear my doubts here.
Thank you.
Well let me clear your doubts,
First of all there aren't any specific number of process for an OS, its called as cores or threads, technically you can define how many cores or threads you want to use on your virtual machine and it depends on the system configuration you use.
Secondly Guest OS is what you have created in the virtual machine and host is what your laptop or pc actually run. Host OS uses the actual hardware for the working whereas the Guest OS uses the virtual hardware like number of cores and type and size of hard drive defined by the user while adding a virtual machine.
Third, as I mentioned earlier Guest and Host OS works on the configurations used by you, if you user higher amount of cores/ threads in setting your virtual machine the Guest OS will get higher speed.
Ideally the virtual machines are used to test and create some functionality of the Operating Systems without affecting the internal OS, so you can think of it as a your parents house where you can live and grow but at the end you cannot go away from the fact that their contribution is more and so you cannot go beyond their features without leaving it and making your own home.
Linux operating systems are multi-threaded operating system. The host OS would consider virtual box as a thread. You can define number of cores and virtual hard disk size for guest OS by using virtual box.
Since virtual box runs in separate thread and other operations of host OS runs in separate threads, there would be less effect on speed of processing. But I've observed big variances in processing speed in systems which have low memory. Each and every thread needs specific allocation of memory for its smooth operation. So systems having more than 2 GB RAM managed virtual box very well.
I have openstack (kvm hypervisor) installed.
I have 32 cores in my host (/proc/stat...gives me that info)
I can start a vm from the host also I can get the cpu utilisation of the vm . I get this by finding the pid of the virtual machine from the host.
However I am not able to figure out is how do I know which virtual machine is running on which of the 32 core.
Is there any way to find it our
Or is there any way to explicitly pin it to a particular cpu?
This answer on ask.openstack.org https://ask.openstack.org/en/question/1282/can-openstack-choose-the-physical-resources-to-boot-a-vm/ indicates that "OpenStack Compute with the libvirt driver has no ability to pin a VM to specific physical CPU."