Re: [OS-BUILD PATCHv5] redhat/kernel.spec.template: Parallelize compression
From: Denys Vlasenko on gitlab.com https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2254#note_1249493515 We usually have 2000..4000 modules. With e.g. -n 1000, you obviously risk having fewer "xz" processes than CPUs. Even with -n 100, conceivably on a big machine, you can underutilize CPUs. OTOH, -n 1, you can spend more time starting a new xz process than compressing a module, if it's a small module. So yes, -n16 is an arbitrary choice, but there is logic why it should be somewhere in [10,100] range. ___ kernel mailing list -- kernel@lists.fedoraproject.org To unsubscribe send an email to kernel-le...@lists.fedoraproject.org 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/kernel@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: [OS-BUILD PATCHv5] redhat/kernel.spec.template: Parallelize compression
From: Herton R. Krzesinski on gitlab.com https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2254#note_1249483495 I don't think we need to overengineer this. I agree fork costs can be something to avoid, but we don't need a separate script. If there is a heuristic for it we should calculate it and and give to ```-n``` option. But I'm ok the way it is right now. If you want to determine an heuristic and measure the difference feel free to. ___ kernel mailing list -- kernel@lists.fedoraproject.org To unsubscribe send an email to kernel-le...@lists.fedoraproject.org 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/kernel@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: [OS-BUILD PATCHv5] redhat/kernel.spec.template: Parallelize compression
From: Prarit Bhargava on gitlab.com https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2254#note_1249133186 I'd argue then the original version (with a separate parallel script) would be preferable than a magic number. @hertonrk-rh, your thoughts? ___ kernel mailing list -- kernel@lists.fedoraproject.org To unsubscribe send an email to kernel-le...@lists.fedoraproject.org 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/kernel@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: [OS-BUILD PATCHv5] redhat/kernel.spec.template: Parallelize compression
From: Denys Vlasenko on gitlab.com https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2254#note_1249068590 "-n 1" will spawn one "xz" per every module. This incurs some startup costs (fork+exec+library loading). How about "-n 16", so that each xz process compresses 16 modules, decreasing startup costs by more than 90%? rhel7 and rhel8 already use this approach. ___ kernel mailing list -- kernel@lists.fedoraproject.org To unsubscribe send an email to kernel-le...@lists.fedoraproject.org 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/kernel@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
