search for: 8vcpu

Hi, I'm booting an qemu VM from a virtual disk. In the success case the virtual console shows something like this: SYSLINUX 4.05 0x54f93f16 Copyright (C) 1994-2011 H. Peter Anvin et al Loading vmlinuz......... Loading initramfs.img...................................ready. [ 0.000000] Initializing cgroup subsys cpuset <etc> In the failure case I'm seeing something like this:

...es up to ~100 seconds for the VM to start running. I suspect > most of that time was spent trying to load this file. > > My assumption is that this is likely an IO problem on the host. Would that > make sense? It's most likely although CPU contention can cause similar symptoms. An 8vCPU VM needs 8 idle cores to have execution time. How many vCPUs (vCPU = vSockets * vCoresPerSocket)? Physical cores (not counting CPU threading)? > Also, can someone point me to the code that emits the dots while loading the > file? core/runkernel.inc calls dot_pause in core/abort.inc -- -...

Hi All, I've been chasing down an issue in recent weeks (my own lab, so no prod here) and I'm reaching out in case someone might have some guidance to share. I'm running fairly large VMs (RHOSP underclouds - 8vcpu, 32gb ram, about 200gb single disk as a growable qcow2) on some RHEL7.6 hypervisors (kernel 3.10.0-927.2x.y, libvirt 4.5.0, qemu-kvm-1.5.3) on top of SSD/NVMe drives with various filesystems (vxfs, zfs, etc..) and using ECC RAM. The issue can be described as follows: - the guest VMs work fine...

...ts we can see that patched kernel performance is similar to BASE when there is no lock contention. But once we start seeing more contention, patched kernel outperforms BASE (non PLE). On PLE machine we do not see greater performance improvement because of PLE complimenting halt() 3 guests with 8VCPU, 4GB RAM, 1 used for kernbench (kernbench -f -H -M -o 20) other for cpuhog (shell script while true with an instruction) scenario A: unpinned 1x: no hogs 2x: 8hogs in one guest 3x: 8hogs each in two guest scenario B: unpinned, run kernbench on all the guests no hogs. Dbench on PLE machine: dben...

...ts we can see that patched kernel performance is similar to BASE when there is no lock contention. But once we start seeing more contention, patched kernel outperforms BASE (non PLE). On PLE machine we do not see greater performance improvement because of PLE complimenting halt() 3 guests with 8VCPU, 4GB RAM, 1 used for kernbench (kernbench -f -H -M -o 20) other for cpuhog (shell script while true with an instruction) scenario A: unpinned 1x: no hogs 2x: 8hogs in one guest 3x: 8hogs each in two guest scenario B: unpinned, run kernbench on all the guests no hogs. Dbench on PLE machine: dben...

...From the results we can see that patched kernel performance is similar to BASE when there is no lock contention. But once we start seeing more contention, patched kernel outperforms BASE. set up : Kernel for host/guest : 3.2-rc1 + Jeremy's xadd, pv spinlock patches as BASE 3 guests with 8VCPU, 4GB RAM, 1 used for kernbench (kernbench -f -H -M -o 20) other for cpuhog (shell script while true with an instruction) scenario A: unpinned 1x: no hogs 2x: 8hogs in one guest 3x: 8hogs each in two guest Result for Non PLE machine : Machine : IBM xSeries with Intel(R) Xeon(R) x5570 2.93GHz CPU...

...From the results we can see that patched kernel performance is similar to BASE when there is no lock contention. But once we start seeing more contention, patched kernel outperforms BASE. set up : Kernel for host/guest : 3.2-rc1 + Jeremy's xadd, pv spinlock patches as BASE 3 guests with 8VCPU, 4GB RAM, 1 used for kernbench (kernbench -f -H -M -o 20) other for cpuhog (shell script while true with an instruction) scenario A: unpinned 1x: no hogs 2x: 8hogs in one guest 3x: 8hogs each in two guest Result for Non PLE machine : Machine : IBM xSeries with Intel(R) Xeon(R) x5570 2.93GHz CPU...

...l/2012/3/21/161) Results: The performance gain is mainly because of reduced busy-wait time. From the results we can see that patched kernel performance is similar to BASE when there is no lock contention. But once we start seeing more contention, patched kernel outperforms BASE. 3 guests with 8VCPU, 8GB RAM, 1 used for kernbench (kernbench -f -H -M -o 20) other for cpuhog (shell script while true with an instruction) 1x: no hogs 2x: 8hogs in one guest 3x: 8hogs each in two guest 1) kernbench Machine : IBM xSeries with Intel(R) Xeon(R) x5570 2.93GHz CPU with 8 core , 64GB RAM BASE...

...l/2012/3/21/161) Results: The performance gain is mainly because of reduced busy-wait time. From the results we can see that patched kernel performance is similar to BASE when there is no lock contention. But once we start seeing more contention, patched kernel outperforms BASE. 3 guests with 8VCPU, 8GB RAM, 1 used for kernbench (kernbench -f -H -M -o 20) other for cpuhog (shell script while true with an instruction) 1x: no hogs 2x: 8hogs in one guest 3x: 8hogs each in two guest 1) kernbench Machine : IBM xSeries with Intel(R) Xeon(R) x5570 2.93GHz CPU with 8 core , 64GB RAM BASE...

This series replaces the existing paravirtualized spinlock mechanism with a paravirtualized ticketlock mechanism. The series provides implementation for both Xen and KVM.(targeted for 3.5 window) Note: This needs debugfs changes patch that should be in Xen / linux-next https://lkml.org/lkml/2012/3/30/687 Changes in V8: - Reabsed patches to 3.4-rc4 - Combined the KVM changes with ticketlock

This series replaces the existing paravirtualized spinlock mechanism with a paravirtualized ticketlock mechanism. The series provides implementation for both Xen and KVM.(targeted for 3.5 window) Note: This needs debugfs changes patch that should be in Xen / linux-next https://lkml.org/lkml/2012/3/30/687 Changes in V8: - Reabsed patches to 3.4-rc4 - Combined the KVM changes with ticketlock