2100610 - Downgrade from ASE 15.7 SP130 to ASE 15.5 hangs or is running extremely slow.

• Downgrade from ASE 15.7 SP130 to ASE 15.5 hangs or is running extremely slow.
   
• A server process executing  sp_downgrade seems like hanging for hours at Step 999 at the very end of downgrade process.
  This is the end of the output:

1> sp_downgrade 'downgrade', @toversion='155', @override=1, @verbose=1
2> go
@fromversid = 15700' @fromversion = '15.7.0.0' @toversid = 155
Downgrade from 15.7.0.0 to 15.5.0.0 (command: 'downgrade')
...
Executing downgrade step 999 [declare @d int select @d=dbinfo_update(@dbid, 'ASEvers', 15500)] for :
- Database: master (dbid: 1)
- Database: tempdb (dbid: 2)
- Database: model (dbid: 3)
- Database: mydb1 (dbid: 4)
- Database: mydb2 (dbid: 5)
- Database: auditdata (dbid: 6)
- Database: mda_history (dbid: 8)
- Database: sybsystemdb (dbid: 31513)
- Database: sybsystemprocs (dbid: 31514)
- Database: dbccdb (dbid: 31515)
 
Dropping and recreating index on Sysprotects for database master
DBCC execution completed. If DBCC printed error messages, contact a user with System Administrator (SA) role.
 
Dropping and recreating index on Sysattributes for database master
DBCC execution completed. If DBCC printed error messages, contact a user with System Administrator (SA) role.
 
Dropping and recreating index on Sysprotects for database tempdb
DBCC execution completed. If DBCC printed error messages, contact a user with System Administrator (SA) role.
 
Dropping and recreating index on Sysattributes for database tempdb
DBCC execution completed. If DBCC printed error messages, contact a user with System Administrator (SA) role.
 
Dropping and recreating index on Sysprotects for database model
DBCC execution completed. If DBCC printed error messages, contact a user with System Administrator (SA) role.
 
Dropping and recreating index on Sysattributes for database model

SAP Adaptive Server Enterprise (ASE) 15.7

775241, CR775241, async, log, service, CR#775241 , KBA , BC-SYB-ASE , Sybase ASE Database Platform (non Business Suite) , Bug Filed