@lathiat: > - Is there some specific hardware where scaling-driver=pcc-cpufreq > and scaling-governor=ondemand performs poorly. I have yet to run a > benchmark on my example hardware to find out.
Yes, we first started seeing this when deploying new Ubuntu Archive servers where we had two servers in the same DC taking on the same amount of traffic/requests. One was showing much higher load and performing much worse than the other. We brought up others in another DC and saw the same. The internal ticket, RT#90571, has some details. The specs differ with the one without issues being: | economy - HP ProLiant DL380 G7 The ones that were showing issues are: | hanger - HP ProLiant DL360p Gen8 | steelix - ProLiant DL380 Gen9 | keeton - ProLiant DL380p Gen8 By default, they're using the pcc-cpufreq but we also tried acpi-cpufreq which didn't seem to have made any difference. This led to us filing LP: #1579278 and the change to a piece of software we use to deploy disabling the 'ondemand' CPU governor: | https://bazaar.launchpad.net/~canonical- sysadmins/basenode/trunk/revision/98 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1806012 Title: set-cpufreq: 'powersave' governor configuration sanity on ubuntu server Status in systemd package in Ubuntu: In Progress Status in systemd source package in Xenial: In Progress Status in systemd source package in Bionic: In Progress Status in systemd source package in Cosmic: In Progress Status in systemd source package in Disco: In Progress Bug description: Whilst debugging 'slow instance performance' on a Ubuntu Bionic based cloud, I observed that the default cpu governor configuration was set to 'powersave'; toggling this to 'performance' (while in not anyway a particularly green thing todo) resulted in the instance slowness disappearing and the cloud performance being as expected (based on a prior version of the deploy on Ubuntu Xenial). AFAICT Xenial does the same thing albeit in a slight different way, but we definitely did not see the same performance laggy-ness under a Xenial based cloud. Raising against systemd (as this package sets the governor to 'powersave') - I feel that the switch to 'performance' although appropriate then obscures what might be a performance/behavioural difference in the underlying kernel when a machine is under load. ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: systemd 237-3ubuntu10.9 ProcVersionSignature: Ubuntu 4.15.0-39.42-generic 4.15.18 Uname: Linux 4.15.0-39-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.5 Architecture: amd64 Date: Fri Nov 30 10:05:46 2018 Lsusb: Bus 002 Device 002: ID 8087:8002 Intel Corp. Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 003: ID 413c:a001 Dell Computer Corp. Hub Bus 001 Device 002: ID 8087:800a Intel Corp. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub MachineType: Dell Inc. PowerEdge R630 ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=C.UTF-8 SHELL=/bin/bash ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-39-generic root=UUID=a361a524-47eb-46c3-8a04-e5eaa65188c9 ro hugepages=103117 iommu=pt intel_iommu=on SourcePackage: systemd UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 11/08/2016 dmi.bios.vendor: Dell Inc. dmi.bios.version: 2.3.4 dmi.board.name: 02C2CP dmi.board.vendor: Dell Inc. dmi.board.version: A03 dmi.chassis.type: 23 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvr2.3.4:bd11/08/2016:svnDellInc.:pnPowerEdgeR630:pvr:rvnDellInc.:rn02C2CP:rvrA03:cvnDellInc.:ct23:cvr: dmi.product.name: PowerEdge R630 dmi.sys.vendor: Dell Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1806012/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
