HP StorageWorks Storage Mirroring Recover User's Guide (T5437-96008, November 2009)

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that next operation. Also, if one operation is larger than the defined size
limit, the entire operation will be written to one transaction log.
3. When system memory is full, the most recent changed data is added to the disk
queue, as described in step 2. This means that system memory contains the oldest
data. Therefore, when data is transmitted to the target, Storage Mirroring Recover
pulls the data from system memory and sends it. This ensures that the data is
transmitted to the target in the same order it was changed on the source. Storage
Mirroring Recover automatically reads operations from the oldest transaction log
file into system memory. As a transaction log is depleted, it is deleted. When all of
the transaction log files are deleted, data is again written directly to system memory
(step 1).
4. To ensure the integrity of the data on the target, the information must be applied in
the same order as it was on the source. If there are any delays in processing, for
example because of a locked file, a similar queuing process occurs on the target.
Data that cannot immediately be applied is queued to system memory. By default,
128 or 512 MB of memory is used, depending on your operating system.
5. When the allocated amount of system memory on the target is full, new incoming
data bypasses the full system memory and is queued directly to disk. Data queued
to disk is written to a transaction log. On the target, the transaction logs are
identified with the source IP address, the Storage Mirroring Recover port, the
connection ID, and an incrementing sequence number.
Like the source, system memory on the target contains the oldest data so when data is
applied to the target, Storage Mirroring Recover pulls the data from system memory.
Storage Mirroring Recover automatically moves operations from the oldest transaction
log file to system memory. As a transaction log is depleted, it is deleted. When all of the
transaction log files are deleted, data is again written directly to system memory (step 4).
Queuing data
You should configure queuing on both the source and target.
1. Open the Replication Console and right-click the server on the left pane of the
Replication Console.
2. Select Properties.
3. Select the Queue tab.
4. Specify the queue settings for the server.