Description

Through the qview utility, you can view queue names and remove old queue files. The qview tools described here do not deactivate the configuration.

IMPORTANT!Do not use qview for the first time without the assistance of Quest Technical Support. If this utility is not used properly, it can damage the replication environment and require resynchronization and reactivation.

Supported databases

All SharePlex-supported databases on all supported platforms

Run qview

Log on to the system as a SharePlex Administrator, and use the command line of the operating system to run qview from the bin sub-directory of the SharePlex product directory. The utility is an interactive command session.

To run qview on the Windows platform, log onto the system as a member of the Administrators group. Run qview from a command prompt or powershell which was run by right clicking on its icon and selecting run as administrator.

On Windows, run qview with the -p option to specify the port number of the SharePlex instance for which you want to view queues.

qview -pport list

Overview of qview commands

The qview utility provides the following commands:

Command	Description
list	Lists all queues for all active configurations on a system.
trim	Clean up obsolete subqueue files.
fullrb	Create a full rollback message.
otrans	Scans for a specified number of messages in the Capture queue.

List queues

Use the list command to list all queues for all active configurations on a system.

Description

The qview list command lists each queue, the replication process that writes to it, and the replication process that reads it. For example, for the capture queue, it lists the Capture process and the Read process. The queues are designated as follows:

• A capture queue is designated with a +C.
• An export queue is designated with a +X.
• A post queue is designated with a +P.

Example output:

In this example, the writer to the capture queue o.ora11+C is the Capture process, as indicated by the sp_ocap in its name string. The reader is the Read process, as indicated by the sp_ord in its name string. The same naming logic applies to the other queues shown in the output (export queue expdsg+X and post queue expdsg+P).

The following queues exist:
o.ora11+C
	WRITER +PA+o.ora11+sp_ocap+o.ora11
	READER +PR+o.ora11+sp_ordr+o.ora11
elliot+X
	WRITER +PR+o.ora11+sp_ordr+o.ora11
	READER +PX+elliot+sp_xport+0x0a01014e (11.1.1.78)
elliot+P+o.ora11-o.ora11
subqueues range from 2 to 6
	WRITER +PI+elliot+sp_mport+0x0a01014e (11.1.1.78)
	READER +PP+elliot+sp_opst_mt+o.ora11-o.ora11

Syntax

list

Trim obsolete subqueues

Use the trim command to clean up obsolete subqueue files on the source system.

Description

The SharePlex post queue actually consists of a number of subqueues, each approximately corresponding to a user session on the source system. The Post process uses the subqueues to establish Oracle sessions for the target instance. The number of subqueues that exist at a given time on a target system reflects the peak activity on the source system since replication started.

SharePlex routinely writes replicated data from the subqueues to associated datafiles on disk as part of its checkpoint recovery system. Each subqueue can have one or more datafiles associated with it, each with a default size of 8 MB. If the entire 8 MB file size is not consumed, a datafile remains on the system even though the data was posted and read/released. Consequently, the higher the activity level on the source system, the more datafiles on disk. The size in megabytes (MB) for the post queue in a qstatus display is the actual disk space that the datafiles occupy.

For example, suppose there were 100 concurrent sessions on the source system, creating 100 subqueues in the post queue on the target system. And, suppose the datafiles were only partially full when the activity level dropped—half full, for example, or 4 MB of 8 MB used—and thus were not deleted. The post queue on that system would consist of 100 datafiles at 4 MB each, totalling 400 MB of disk space.

Using the trim command in qview, you can routinely eliminate obsolete subqueue files that were read-released, while preserving the ones containing data not yet committed to the target database. The trim command does not eliminate queue files for subqueues 0 or 1, because those are the most heavily used subqueues.

How to run this command

Run this command on the target system only.

Stop Import and Post before running qview to issue this command. You can leave sp_cop running.

Note: If one or both of those processes is not stopped, qview returns this error message: que_INUSE: Que is already open.

You can only trim one queue at a time. If there are more than one post queue, you are prompted to select the one you want the command to affect:

Queue zac+P+o.ora920-o.ora920 (y/n) <n>? n
Queue elliot+P+o.ora920-o.ora920 (y/n) <n>? y

Note: If you do not select a queue, qview returns this error message: que_NOEXIST: Queue does not exist.

Syntax

trim

Execute a full rollback

Use the otrans and fullrb commands to create a full rollback message.

Description

Use the otrans command to scan a specified number of messages in the Capture queue, starting at the read release point. The qview utility then prints the transaction id, the number of operations (records), the DML type operation (if there is only one) and the object id modified (if there is only one).

Use the transaction id obtained from otrans to execute fullrb. The qview utility opens the Capture queue, writes an out-of-band full rollback message to the Capture queue, and then writes a commit.

How to run this command

1. Stop Capture.
2. Run qview.

3. Issue the otrans command.

   vqiew> otrans 500000

   The output is similar to the following:

   Full rollback 8(7).752562-3(139) --- 99999 Update operations on object id 466857
   Open transaction 8(23).752700-2(14162) --- 2001 Update operations (1000 backward operations) 
   on object id 466857

4. Issue the fullrb command using the transaction ID from the otrans output.

   vqiew> fullrb 8(7).752562-3(139)

   The output is similar to the following:

   Current queue o.ora920+C        user +PA+o.ora920+sp_ocap+o.ora920
   Full rollback record written to capture queue at 378744, id 1102
   odr_magic        0x4f445235
   odr_op           ODR_FULL_ROLLBACK (50)
   odr_trans        8(7).752562-3(139)
   odr_time         01/01/88 00:00:00 (0)

5. Start Capture.

   sp_ctrl> start capture

Syntax

otrans number

where: number is the number of messages to scan in the queue.

fullrb transaction_ID

where: transaction_ID is the transaction ID that was returned from otrans.