1. Microservices Architecture Documentation
  2. Administer
  3. Trail File Management
  4. Estimate Space for the Trails

Estimate Space for the Trails

The following are guidelines for estimating the amount of disk space that will be required to store Oracle GoldenGate trail data.

  1. Estimate the longest time that the network could be unavailable. Plan to store enough data to withstand the longest possible outage, because otherwise you will need to resynchronize the source and target data if the outage outlasts disk capacity.

  2. Estimate how much transaction log volume your business applications generate in one hour.

  3. Use the following formula to calculate the required disk space.

    [source transaction log volume in one hour] x [number of hours downtime] x .4 = trail disk space

    This equation uses a multiplier of 40 percent because only about 40 percent of the data in a transaction log is needed by Oracle GoldenGate.

    Note:

    This formula is a conservative estimate, and you should run tests once you have configured Oracle GoldenGate to determine exactly how much space you need. As a general observation, in case of subset replication, the required trail disk space might be much lower.

To prevent trail activity from interfering with business applications, assign a separate disk or file system to contain the trail files. Trail files can resides on local storage, network-attached storage (NAS, SAN), shared filesystem, or cluster file system (ACFS, DBFS).