Updated Host-Based MiniMerge Schedule

Updated Host-Based MiniMerge Schedule

Post by Sue Skonets » Fri, 04 Jul 2003 22:53:01



Dear Newsgroup,

Please note this updated information.  This looks much better in rich
txt or word.

Warm Regards,
Sue

____________________________________________________________
Host-Based MiniMerge Schedule Now Available

The OpenVMS Engineering and Business Management group would like to
announce the schedule for Host-Based MiniMerge capability.  As most of
you know, the teams have been spending virtually all of their time
over the past 3 months doing design, "proof of concept" and schedule
development for this important feature.  We are now ready to make this
information available to the OpenVMS user community.

Overview The purpose of the Host-Based MiniMerge feature is to allow
a "minimum" MERGE of only shadow set changes (rather than the
currently-required "full" MERGE) when a member of an OpenVMS cluster
is removed and re-introduced into a cluster.  A similar capability
exists today for CI-based storage, and this new "host-based"
implementation will allow a MiniMerge to occur on any type of storage
that is utilized in a Host-Based Volume Shadowing shadow set.

Technical Description - This implementation utilizes the "write
bitmap" technology used for MiniCopy functionality today, to keep
track of shadow set data changes while a shadowset member is
temporarily removed from a shadowset.  With MiniCopy, when a shadowset
member is brought back in, Shadowing is able to copy only the changed
areas of the disk, thus resulting in a much faster restoration of the
shadow set member into the shadowset.  By using similar "write bitmap"
technology to track the changes being made by each node in a cluster
to the members of a shadowset, then at the time a node fails and
leaves the cluster, it is possible to identify those specific areas on
the shadowset that were being written to by the node at the time it
failed.  As such, where the failure might have resulted in data ending
up different on different members of the shadowset, Shadowing can now
merge just those areas which were in the process of being modified at
the time the node failed (in a MiniMerge operation), rather than
having to scan the entire disk looking for potential discrepancies
caused by the node's failure (in a Full Merge operation).

Schedule/Version Summary - Below is a schedule with major milestones
for this engineering effort.  The important date is that customer
availability of this feature will be on 25-March-2004 for the OpenVMS
V7.3-1 customer base.  Support for OpenVMS V7.3-2 will be shortly
thereafter.

We will do periodic updates to the field of the status of this
engineering effort, and also solicit candidates for beta testing of
this feature, which is scheduled to occur at the end of 2003.  If
there are any questions, please contact either Jim Janetos


Host-Based MiniMerge Schedule                                     6/30/03

Task Name       Start   Completion
HBMM Features (code and debug)          
Minimerge from a bitmap (essentials)    6/20/2003       8/15/2003
Bitmap Reset    6/19/2003       9/25/03
Merge Priority  6/24/2003       9/25/03
Master Bitmap Policy    6/19/2003       10/01/03
HBMM code and debug phase complete      06/17/03        10/20/03
Performance characterization    06/17/2003      10/09/03
User documentation      7/14/03 11/20/03
Internal testing and Qualification      10/10/03        12/29/03
External Field Test     12/31/03        3/24/04
V7.3-1 Based Production Kit available           3/25/04

 
 
 

1. OpenVMS Host-Based MiniMerge Statement and Schedule for Customers

There was a word schedule attached but I know how you folks feel about
that.

sue

----------------------------------------------------

Host-Based MiniMerge Schedule Now Available

The OpenVMS Engineering and Business Management group would like to
announce the schedule for Host-Based MiniMerge capability.  As most of
you know, the teams have been spending virtually all of their time
over the past 3 months doing design, "proof of concept" and schedule
development for this important feature.  We are now ready to make this
information available to the OpenVMS user community.

Overview - The purpose of the Host-Based MiniMerge feature is to allow
a "minimum" MERGE of only shadow set changes (rather than the
currently-required "full" MERGE) when a member of an OpenVMS cluster
is removed and re-introduced into a cluster.  A similar capability
exists today for CI-based storage, and this new "host-based"
implementation will allow a MiniMerge to occur on any type of storage
that is utilized in a Host-Based Volume Shadowing shadow set.  This
implementation utilizes the "write bitmap" technology in use with
MiniCopy today, in order to keep track of shadow set data changes
while the cluster member is out of the cluster.  When the member is
brought back in, shadow sets will be able to MERGE only the changed
areas of the disk, thus resulting in a much faster restoration of
shadow sets into the cluster.

2. Strange PPRO 200 Problem

3. Host-based vs. controller-based shadowing

4. Reduce or eliminate flicker on a1000?

5. XTORY II MSX CD-ROM

6. Host-based volume shadowing out to get me again

7. Host-based volume shadowing a system disk?

8. VMS/AXP Host-based RAID Problem

9. Alternatives to Host-Based Volume Shadowing

10. Host-Based Shadowing - Potential Loss of Data?

11. host-based shadow question