March 2009

https://bugzilla.mozilla.org/show_bug.cgi?id=421482

------- Comment #123 From Andrew Morton 2008-05-22 21:26:02 PDT -------

Life's too short to read through all this, but...

yes, ext3 does suck-by-design. Always has.

I would commend the use of the sync_file_range() syscall on Linux. It
can be used to sync a subsection of a file and will not trigger the
write-the-whole-world behavior. It will just sync the stuff you want
sunk.



意訳:
このスレッドを全部読むには人生は短すぎる。でも・・・
Yes. ext3 はデザインからして最低です。


突然、firefoxのbugzillaに現れてext3を罵倒して去っていくAndrew。あんたサイコー
文脈もクソもねーな

この話のキモは、Andrewは最近までext3のメンテナーだったという所で。。。
そんなにメンテ苦痛だったのか(^^;

http://headlines.yahoo.co.jp/hl?a=20090321-00000531-yom-int

どうやらマジらしい。
グルジアというと、ゲームで翻訳会社が糞だったりするとよくジョージアになっていて、プゲラッとか笑い飛ばすメッカだったんだが、そうか、なくなってしまうのか。。

ちなみに、イギリスの守護聖人にもなっているジョージさんが、実は小アジアの今のトルコの人であることは、あまり知られていない。

On Tue, 17 Mar 2009, Nick Piggin wrote:
> > Yes, my patch isn't realy solusion.
> > Andrea already pointed out that it's not O_DIRECT issue, it's gup vs fork
> > issue. *and* my patch is crazy slow :)
>
> Well, it's an interesting question. I'd say it probably is more than
> just O_DIRECT. vmsplice too, for example (which I think is much harder
> to fix this way because the pages are retired by the other end of
> the pipe, so I don't think you can hold a lock across it).

Well, only the "fork()" has the race problem.

So having a fork-specific lock (but not naming it by directio) actually
does make sense. The fork is much less performance-critical than most
random mmap_sem users - and doesn't have the same scalability issues
either (ie people probably _do_ want to do mmap/munmap/brk concurrently
with gup lookup, but there's much less worry about concurrent fork()
performance).

It doesn't necessarily make the general problem go away, but it makes the
_particular_ race between get_user_pages() and fork() go away. Then you
can do per-page flags or whatever and not have to worry about concurrent
lookups.

Linus


Andreaを見かねて助け船を出したつもりが、Linusから「むしろ kosaki パッチをマージすべきじゃね?」とか言われてアゴがはずれそう。
ごめんよAndrea,そんなつもりじゃなかったんだよー

そもそも単語の存在自体を知らなかったよ。

> splice() already has a callback for releasing the pages, so it's doable.

doable, maybe.



Linus: こうやったら出来るんじゃね?
Nick: ・・・たぶんね

とかいう感じで使う

http://eow.alc.co.jp/last+resort/UTF-8/

・ last resort
最後{さいご}の手段{しゅだん}、苦肉{くにく}の策、伝家の宝刀、頼みの綱、最終審{さいしゅうしん}
・I've got to go with the last resort. : こうなったら最後の手段しかない



よく使うよね > 最後の手段

最初に見た時は、「前回行ったリゾート?話そらすなボケ!今はカーネルの話をしとるんじゃ!!」とか思ったものだが :-p

Andrew MortonがNILFSを2.6.30でLinusに送ると発言。


On Wed, 11 Mar 2009 01:55:42 +0900 (JST)
Ryusuke Konishi wrote:

> I've been working for the past serveral months to take review comments
> and to continually solve users' problems come up in mainling list

Yes, the maintenance has been impressive.

> (thanks for all giving comments and feedbacks!). Also, I've tried to
> stabilize API and disk format to restrict additional changes and
> ensure backward compatibility.

Well. From the point of view of mainline linux, there is no
back-compatibility issue, because the fs hasn't been merged yet.

You perhaps have back-compatibility concerns for existing users of the
out-of-tree patch, but I'd encourage you to not worry about that too
much - there will be fairly few users and they are probably pretty
technical and will be able to cope with a migration. It's a _bit_ hard
on them but on the other hand, omitting back-compatibility code leads
to a better implementation for the long term.

What you should be more concerned about is forward-compatibility. What
arrangements do you presently have in place to be able to later alter the
on-disk format without causing too much disruption? Having a strong
design here will make changes easier to do and will lead to a better
filesystem.

Also.. Don't get _too_ concerned about freezing the on-disk format at
this time. You could put in a mount-time printk("the nilfs on-disk
format may change at any time - do not place critical data on a nilfs
filesystem") and we leave that in place for a few months while things
stabilise.

And yes, I was planning on sending nilfs in to Linus for 2.6.30 unless
someone has decent-sounding reasons to hold it back.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/


今日、帰り際に投稿したパッチ、LKMLにccし忘れた気が強烈にする。
Ingoの事だから、即マージしちゃいそうな気がする。まずい

↑このページのトップヘ