Mt Fuji - MMC:

David Burg daviburg at
Mon Aug 27 23:38:39 PDT 2007

* From the T10 Reflector (t10 at, posted by:
* David Burg <daviburg at>
Hi Katata-san,
Thank you for the refreshed information on the Pioneer implementation.
I agree we need to work on the Set Streaming command so that its description
both better match what devices implement and better match what is reasonable
to implement - like matching the rotation speed for both read and write when
commands are intermixed, yet leave the possibility of higher read rotation
speed when there is no writing.
We need to further work on probably both the get performance and the set
streaming command - possibly even the streaming feature itself - to address
the HD Video on red laser media case brought to us by Toshiba (and in which
Microsoft has interest as well).
Microsoft also needs the devices to more accurately report their performance
capabilities and well as current state so that proper choices and information
can be presented to the user.
There is too a known need for noise control, and we know that some OEM in
particular is sensitive to the issue.
Finally there is a general push for power saving in the industry, and precise
speed control can help reduce the power consumption of optical devices.
Hey, this is probably one of the most complex and most interesting technical
challenges we had in Mt Fuji - MMC in a while.
David Burg.
-----Original Message-----
From: owner-mtfuji5 at [mailto:owner-mtfuji5 at] On
Behalf Of keiji_katata at
Sent: Monday, August 27, 2007 10:54 PM
To: mtfuji5 at
Cc: T10 Reflector
Subject: Re: Mt Fuji - MMC:
Hi David,
Yes, you are right. Live UDF now does not update Access time of the files.
DirectCD to Live UDF, I had confirmed and requested to stop the action. It is
confirmed that softwares stop it. There are no problem.
We need not discuss the hypothetical operating system but you may understand
that OS/FS spec allows the behavior.
I checked Pioneer implementation of the SetStreaming command. My knowledge
I said in the meeting was old and was not correct.
1. Pioneer drive may ignore the Read Seed field (Read Size/Time) (Notes: on
cases, drive refers the field.)
2. Pioneer drive refers the Write Speed filed (Write Size/Time) and sets the
rotation speed as lower or equal speed if possible. This is same as Toshiba.
3. When writing occurs or when SetStreaming command is received, drive sets
rotation speed according to the write speed. Always reading speed is set to
as writing speed.
4. In the case of CD/DVD-R/RW, BD-R, when a session is closed the reading
is set to maximum.
5. Drive remembers the last SetStreaming command then if next writing occurs,
drive performs the step no.3.
The reason why the reading speed is adjusted to same as writing speed is that
the data writing has the highest priority than any. Drive automatic verify or
host read operation for verify are performed by writing speed. Because all of
setting (spindle servo, pick up servo, equalizer, etc) are adjusted for the
writing speed. When rotation speed is changed unstable condition will
for some time length. This is not acceptable.
And buffered data writing and rotation speed change on a Read command may be
cause of time-out of the host.
I think we have two problems in the current SetSteaming command.
1. Drive may select lower or equal speed if possible on the current
command. This is not the next highest or equal.
2. When writing occurs drive may adjust its rotation speed for the data
not for the data reading.
Best regards,
Keiji Katata
David Burg <daviburg at> on 2007/08/10
mtfuji5 at avc-pioneer.comに返信してください
送信者:     owner-mtfuji5 at
宛先:  <keiji_katata at>
cc:    <mtfuji5 at>, T10 Reflector <t10 at>
件名:  Mt Fuji - MMC:
Dear Katata-san,
My understanding is that you claimed at this week’s Mt Fuji meeting that
Live file system will issue write commands to write-once and rewritable discs
even if the content is only played back, due to update of access time file
properties. Thus you felt the necessity for the Mt Fuji ‐ MMC standardized
devices to workaround a mix of read and writes even for playback
I have discussed with the development lead for Vista Live file system. He
confirmed that we not update the access time on the files. This is disabled
default. If you observe such issue, something else is probably going on,
creating desktop.ini files etc. Ravinder has not seen this for a long time
Vista Live file system seems pretty stable. Please provide particular
and steps taken to reproduce this if you still observe such issue so
team can investigate and fix the problem.
Accordingly, the standard definition shall not be changed and work on future
standard does not need to workaround an hypothetical operating system
implementation problem.
Best regards,
David Burg.
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