LKML Summary Podcast

Audio: COMING SOON

For Thursday, December 24th, 2009, I’m Jon Masters with a summary of today’s LKML traffic.

In today’s issue: ELF, and NFS.

ELF. Hatayama Daisuke posted the latest version of his ELF coredump patches supporting “extended numbering”. As covered previously, this is required when a large number of mmap()’d VMAs causes the number of sections in a dump to exceed the regular 64K limit. The “extended numbering” is similar to that implemented for other ELF based systems.

NFS. Quentin Barnes experienced some frustration with how Linux implements O_DIRECT file semantics over NFS, in which both readahead is disabled and the VFS re-fetches file attributes frequently rather than cacheing them. In order to avoid this, Quentin opens files without O_DIRECT and instead uses a POSIX fadvise call to instruct the kernel to only disable the readahead semantics. But this has the further unexpected problem of causing the kernel to switch to single page reads at a time! He posted a patch that changes the switch to single page reads in the case of disabling readahead but has “no idea” if this is the best approach, and is seeking some further comments.

In today’s announcements: Linux 2.6.33-rc2. Linus Torvalds, wishing everyone a “Merry Christmas..or [whatever] you’re celebrating today/tomorrow”, posted an updated 2.6.33-rc2 release. Whether you celebrate the holiday or not, Linus has a solution for you that involves testing and playing with the new kernel: “Because while your pants may not fit you for the next month, the new kernel might just fit your computer perfectly.” The latest kernel was released at 14:00 Best Coast Time (PST).

The latest kernel release was 2.6.33-rc2.

Stephen Rothwell posted a linux-next tree for December 24th. The main issues with today’s tree were interactions with the kfifo patches which went into Linus’ tree on the previous day and the kgdb patches. Thanks to Stephen for including a summary of changes – if you do so in future, I will use that. This Christmas tree had all the normal build testing at the end but has not had the usual build testing between merges, likely due to the holiday. The total sub-tree count remained steady at 155 trees in the latest compose.

That’s a summary of today’s Linux Kernel Mailing List traffic, for further information visit www.kernel.org. I’m Jon Masters.

Folks,

I’m currently in Paris recovering from a cold and trying to have a little downtime too. So I’m just writing briefer summaries for the holidays and playing a little catchup each day. I will be heading home to the States by way of the UK, and will try to get some recordings caught up before the New Year.

Someone mentioned the audio is currently “zero bytes long”. Actually, that’s not true. The only “official” audio feed (the one that says “Podcast Feed” next to a picture of headphones) is the one listed on kernelpodcast.org on the main page, not the one attached in the RSS feed of each podcast (and the official one hasn’t been updated while I’ve been stuck in blizzards and travelling). That is generated by wordpress when I make a posting with an mp3 reference in it. Since I won’t have audio for a few days, if you’re pulling the wordpress feed then you will still continue to get warnings as there is no audio attached.

Happy (secular) holidays from me, and a happy New Year!

Jon.