2002-07-20 02:04:24

by Hans Reiser

[permalink] [raw]
Subject: Re: [2.6] Most likely to be merged by Halloween... THE LIST]

Rik van Riel wrote:

>On Sat, 20 Jul 2002, Hans Reiser wrote:
>
>
>
>>What I was advocating was a schedule of:
>>1) feature submission deadline
>>2) period of working through feature backlog
>>3) feature acceptance ending date
>>
>>
>
>So, what feature are you trying to smuggle into the kernel
>but are afraid isn't ready on time and why do you think it
>couldn't be backported into 2.6 later, when 2.6 is stable ?
>
Ouch. He sees right though me.;)

The core Reiser4 code should be in time. Reiser4 will have its core
code stable in a month I hope, and by core code I mean code that does
what V3 does but on top of a plugin infrastructure and faster than V3 in
at least some measures.

What I am worried about schedule-wise are:

* the API for exporting transactions to user space (the in kernel buffer
management code to support it is completed but the API is not yet done).
Uses the new system call we are adding.

* The traditional file API is designed for efficiency of repeated
operations to the same file. As part of our effort to make files able
to do everything that extended attributes can do, but more flexibly, we
are creating a new system call. This new system call can perform
multiple operations on files in one system call, and is very convenient
for a bunch of small IOs to different files.

* file inheritance

Some other reiser4 things won't make it, but they seem like they should
be easier to get in later because they are plugins:

* encryption plugin

* ACL plugin

* audit plugin

In our development we started from the bottom layer and worked upwards,
which means the new system call is close to last.

So, I am assuming a new system call must go in before feature freeze.
One can reasonably argue that because it only affects one experimental
filesystem named reiser4 (until other FS authors see how nice it is and
start to use it;-) ) and does not complicate VFS, it is not core code,
and should not be subject to the freeze. I'll make that argument if we
don't have it ready in time....;-)

>
>I can't really think of anything that couldn't be backported
>later on, by the time people start actually using 2.6, but
>maybe you've got something so fundamental it just has to be
>merged before the feature freeze ... ;)
>
>regards,
>
>Rik
>
>


--
Hans




2002-07-20 03:08:18

by Oliver Xymoron

[permalink] [raw]
Subject: Re: [2.6] Most likely to be merged by Halloween... THE LIST]

On Sat, 20 Jul 2002, Hans Reiser wrote:

> Rik van Riel wrote:
>
> >So, what feature are you trying to smuggle into the kernel
> >but are afraid isn't ready on time and why do you think it
> >couldn't be backported into 2.6 later, when 2.6 is stable ?
> >
> Ouch. He sees right though me.;)
>
> The core Reiser4 code should be in time. Reiser4 will have its core
> code stable in a month I hope, and by core code I mean code that does
> what V3 does but on top of a plugin infrastructure and faster than V3 in
> at least some measures.
>
> What I am worried about schedule-wise are:
>
> * the API for exporting transactions to user space (the in kernel buffer
> management code to support it is completed but the API is not yet done).
> Uses the new system call we are adding.

You'd better start hashing that API out on the list yesterday.

> * The traditional file API is designed for efficiency of repeated
> operations to the same file. As part of our effort to make files able
> to do everything that extended attributes can do, but more flexibly, we
> are creating a new system call. This new system call can perform
> multiple operations on files in one system call, and is very convenient
> for a bunch of small IOs to different files.

And this one.

> * file inheritance

And possibly this. Is this transparency of some form?.

> So, I am assuming a new system call must go in before feature freeze.
> One can reasonably argue that because it only affects one experimental
> filesystem named reiser4 (until other FS authors see how nice it is and
> start to use it;-) ) and does not complicate VFS, it is not core code,
> and should not be subject to the freeze. I'll make that argument if we
> don't have it ready in time....;-)

It only doesn't complicate VFS because we haven't discussed generalizing
it yet. The desire to do transactional processing is not unique to Reiser
any more than journalling is. See recent thread about fsync and MTAs.

If you hide all your nifty features under a carpet (aka ioctl) where no
one but Viro notices them, then maybe you'll be able to push this stuff
late September and get them in. But FS-specific syscalls are a non-starter
- what happens to the second FS that decides it wants transactions or
multi-file I/O but doesn't quite fit your model?

--
"Love the dolphins," she advised him. "Write by W.A.S.T.E.."