On Tue, Jun 21, 2022 at 3:11 PM Matthew Miller <mattdm@xxxxxxxxxxxxxxxxx> wrote: > > On Sun, Jun 19, 2022 at 01:36:22PM -0700, Gordon Messmer wrote: > > can probably just treat as a proxy for RHEL performance.) Clear and > > RHEL (rebuilds) probably get most of their advantages from building > > for an x86_64-v2 microarchitecture, which Fedora discussed and > > rejected last year (after discussing and rejecting a proposal to > > build for x86_64-v3 two years before that.) If you exclude Clear > > > Phoronix credits this to those distros shipping with P-state Performance by > default. In order to figure out what's really the best there as a default > for users (rather than benchmarks), I think we'd need to do some significant > testing with real-world workloads for latency, throughput, and power > consumption. (It might be something where we'd want a different default for > Fedora Workstation than for Server or IoT...) P-state can help in some areas, though the new AMD P-state bits last showed to be both slower, and worse on power usage. I do expect that will change soon enough. These are things we do keep an eye on to some extent. Though I don't have an army of people dedicated to benchmarking rounds with various kernels. It might be an interesting experiment at some point. Overall Fedora does willingly sacrifice a little bit of performance for power savings, and (unfortunately) for security. Though almost all of these settings can be overridden with the kernel command line. Again, it might be worth a write up at some point, what kind of performance gain on average one can expect by changing those defaults with command line options, and what you are giving up by doing so. "This feature adds an average 5% overall performance on cpu family X, but sacrifices 11% of battery life", that type of thing. But it would take a reasonable effort to coordinate that, verify it across CPU families, etc. I do say unfortunately on the security part, because these didn't give us much choice. These mitigations were not some well designed system to improve security, with options put forth, and time to fine tune like several of our security features were. They were harsh workarounds to shortcomings of hardware. They have been optimized over time, but there is only so much that can be done. Does every user need all of these turned on? Probably not, but it is better to default to safety until a user can determine whether their particular environment needs a particular mitigation or not. > -- > Matthew Miller > <mattdm@xxxxxxxxxxxxxxxxx> > Fedora Project Leader _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam on the list, report it: https://pagure.io/fedora-infrastructure
