This message is from the T13 list server.
I have not been present at any of the discussions, but Out-Of-Order writes are inherently dangerous to ANY file system - not only to journaling. Now that we have Flush Cache as a mandatory command, why don't we simply issue the Flush Cache to force unit access. I have not heard any real benefit for such a dangerous operation. Why would anyone even consider it ? ...Harlan on 6/19/03 10:49 PM, [EMAIL PROTECTED] wrote: >This message is from the T13 list server. > > > >Steve, > >This totally nukes and destroys write ordered operations. >Example is the down/commit block on a journalled operation. > >Taking an FUA command to platter and blasting past the queue cache will >destroy every bit of the security designed into any journaling file >system. > >I still do not get why MicroSoft thinks there journaling NTFS of the >meta data in OS buffer cache will not take a hit. If I knew the OS my >data was dependent on did such a "FOOLISH" operation I would find another. > >If T13 continues to move towards making it possible for the HOST to do bad >things, then the DEVICE is even worse. > >We can all pack our bags and go home and switch to T10, because nobody >will trust a device coming out of T13 again. > >Comments? > >Tomato Shield UP!! > >Andre Hedrick >LAD Storage Consulting Group > >On Wed, 18 Jun 2003, Steve Livaccari wrote: > >> This message is from the T13 list server. >> >> >> >> All modern HDD's have a buffer for write cache that is used to stack up >> write data from both queued and unqueued write commands. A write command >> followed by a flush cache command will likely not move the data from the >> last write command to the media until the rest of the data is the write >> cache is written. If a write FUA command is used the data from the write >> FUA command will be given priority over the other data in the write cache >> and be written first. >> >> >> >> Regards, >> Steve Livaccari >> >> Hard Drive Engineering >> IBM Global Procurement >> Internet: [EMAIL PROTECTED] >> Phone (919) 543.7393 >> >> >> > >> "Curtis Stevens" > >> <[EMAIL PROTECTED] To: "T13 List Server" ><[EMAIL PROTECTED]> >> oo.com> cc: > >> Sent by: Subject: Re: [t13] hmmm.. no >comments? >> [EMAIL PROTECTED] > >> rg > >> > >> > >> 06/17/2003 11:09 > >> PM > >> > >> > >> >> >> >> >> This message is from the T13 list server. >> >> >> Gary >> >> As I recall, there were some inacuracies in the proposals as made to >> the >> committee. There were many revisions. The only new FUA commands that make >> sense are the queued ones. All others could be followed by flush cache. >> >> --------------------------- >> Curtis E. Stevens >> 29 Dewey >> Irvine, Ca 92620 >> >> Home: (949) 552-4777 >> E-Mail: [EMAIL PROTECTED] >> >> The face of a child can say it all, especially the mouth part of the >> face... >> ----- Original Message ----- >> From: "Gary Laatsch" <[EMAIL PROTECTED]> >> To: "Curtis Stevens" <[EMAIL PROTECTED]>; "T13 List Server" >> <[EMAIL PROTECTED]> >> Sent: Tuesday, June 17, 2003 4:40 PM >> Subject: Re: [t13] hmmm.. no comments? >> >> >> > Curtis and Hale, >> > >> > Also, to expand upon this. I think Hale's point is the proposal put >> > forth by Nita didn't contain the QUEUE FUA or QUEUE FUA EXT commands and >> he >> > was wondering where they were added or how they were proposed. My memory >> was >> > this was discussed and added at the June 2002 meetings. That is why I >> was >> > wondering if anyone else remembered these discussions. I remember >> > discussing all of this stuff (even Andre's comments about the FUA blowig >> > away the queue) but for some reason it just wasn't captured very well in >> the >> > minutes. >> > >> > Gary Laatsch >> > [EMAIL PROTECTED] >> > >> > ----- Original Message ----- >> > From: "Curtis Stevens" <[EMAIL PROTECTED]> >> > To: "T13 List Server" <[EMAIL PROTECTED]> >> > Sent: Tuesday, June 17, 2003 3:15 PM >> > Subject: Re: [t13] hmmm.. no comments? >> > >> > >> > > This message is from the T13 list server. >> > > >> > > >> > > Hale >> > > >> > > I was there during the discussions and there was no secret >> committee. >> > > Basically, MS stated that they wanted to force meta data to the drive >> > > without blowing the que. This means that although it is possible to >> lose >> > > data, in their application data loss would not occur... >> > > >> > > --------------------------- >> > > Curtis E. Stevens >> > > 29 Dewey >> > > Irvine, Ca 92620 >> > > >> > > Home: (949) 552-4777 >> > > E-Mail: [EMAIL PROTECTED] >> > > >> > > The face of a child can say it all, especially the mouth part of the >> > face... >> > > ----- Original Message ----- >> > > From: "Hale Landis" <[EMAIL PROTECTED]> >> > > To: "T13 List Server" <[EMAIL PROTECTED]> >> > > Sent: Tuesday, June 17, 2003 10:57 AM >> > > Subject: [t13] hmmm.. no comments? >> > > >> > > >> > > > This message is from the T13 list server. >> > > > >> > > > >> > > > I'm curious why there are no comments about the question of the >> > > > origin of the WRITE DMA QUEUED FUA command (where is the proposal?). >> > > > And why no comments on QUEUED EXT commands with large sector counts. >> > > > >> > > > Is this because all these discussions must take place via the "secret >> > > > society"? >> > > > >> > > > Hale >> > > > >> > > > >> > > > >> > > > *** Hale Landis *** www.ata-atapi.com *** >> > > > >> > > > >> > > >> >> >> >> >> >
