Vladislav Zolotarov

> How would it do that? And the roles needs to have the option of installing required packages, creating the user and such since it should be possible to run...

@mykaul this issue has nothing to do with a wall clock in general or NTP in particular. It's about a system (realtime) clock source used for calculating high resolution (nanoseconds...

> I'd be surprised if modern kernel doesn't already pick the 'best' clock source. It doesn't always, @mykaul. Hence the tweaking in perftune.py

> so why not adding hyperv_clocksource_tsc_page to the list in https://github.com/scylladb/seastar/blob/master/scripts/perftune.py#L1087 ? > > one line and it should fix this issue, there is no other clock to pick anyways...

> > Hello, It is very difficult to find recommendations of what clocksource to use. The closing line from this kernal article indicate Hyper-V would be preferred. "Clockevents based on...

> so why not adding hyperv_clocksource_tsc_page to the list in https://github.com/scylladb/seastar/blob/master/scripts/perftune.py#L1087 ? > > one line and it should fix this issue, there is no other clock to pick anyways...

According to this page (https://learn.microsoft.com/en-us/azure/sap/workloads/hana-vm-operations#clock-source-options-in-azure-vms) the recommended order on Azure should be: 1) `tsc` 2) `hyperv_clocksource_tsc_page` The latter should selected if the former is not available

> > According to this page (https://learn.microsoft.com/en-us/azure/sap/workloads/hana-vm-operations#clock-source-options-in-azure-vms) the recommended order on Azure should be: > > > > 1. `tsc` > > 2. `hyperv_clocksource_tsc_page` > > > > The latter...

Ref https://github.com/scylladb/scylladb/issues/17719 Proposed solution: https://github.com/scylladb/scylladb/issues/17719#issuecomment-3356860974

@piodul FYI