Creating sbspaces for Spooled Row Data

• Create all the sbspaces of same default log mode type with the same size.
• Do not use Enterprise Replication row data sbspaces for non-Enterprise Replication activity.
• Ensure that the sbspaces are sufficiently large.

  To determine the size of your spooled row data sbspaces, determine your log usage and then consider how much data you can collect if your network goes down. For example, assume that you usually log 40 megabytes of data each day, but only 10 percent of that is replicated data. If your network is down for 24 hours and you estimate that 4 MB of replicated data are logged each day, the size of the sbspaces you identify for the spooled row data must be a total of at least 4 MB.

  Windows™ Only

  On Windows, increase the resulting size of the sbspace by approximately a factor of two. (The default page size, the way that data maps onto a page, and the number of pages written to disk differs on Windows.)

onspaces -c -S er_sbspace -p /dev/rdsk/c0t1d0s4 -o 0 -s 4000\
    -m /dev/rdsk2/c0t1d0s4 0 \
    -Df "AVG_LO_SIZE=2,LOGGING=OFF" 
 

• AVG_LO_SIZE (average large object size)

  Set this parameter to the expected average transaction size (in KB). The database server uses this value to calculate the metadata size. The minimum value for AVG_LO_SIZE is 2 KB, which is appropriate for Enterprise Replication in most cases. (The default value of AVG_LO_SIZE is 32 KB.) If you set AVG_LO_SIZE to larger than the expected transaction size, you might run out of metadata space. If you set AVG_LO_SIZE too small, you might waste space on metadata.

• LOGGING

  Set this parameter to OFF to create an sbspace without logging. Set this parameter to ON to create an sbspace with logging. Use a combination of logging and non-logging sbspaces for Enterprise Replication. For more information, see Logging Mode for sbspaces.