DCM planning worksheet

Before sending and receiving data, use the DCM planning worksheet to estimate how much free disk space is needed in the generate and receive directories. These directories are typically located at the source and destination databases.
DCM Disk Space Planning Worksheet
1. Source Objects
  • Estimate the average size of the source objects to be transferred.

    For example, if your project hierarchy contains several 100 KB source files and the remainder of the source files are 30 KB or smaller, you might choose 80 KB as a high (safe) estimate of the average source object size.

  average source size = __________________ KB
  • Estimate the number of objects in a regular transfer.

    For example, you might transfer five projects, each of which contains 200 source objects. If you expect an average of 150 members of each project to change between daily transfers, each transfer contains 750 source objects.

    Note: An initial transfer typically contains many more objects than are transferred on a regular basis. For example, five projects with 200 files each yields a minimum of 1,000 source objects in the initial transfer. If the objects are transferred with history, and each source file has an average of six versions, the transfer contains 6,000 source files.
average number of sources = __________________ objects
  • If objects are being transferred with history, at least two objects are transferred for each object that has changed. Therefore, multiply the average number of source objects by a history factor that is equal to 1 if you are transferring without history, or 2 if you are transferring with history.
history factor = __________________ (1 or 2)
  • Estimate the source size.
source size = average source size x
average number of sources x
history factor =

__________________ KB
  • Compute the total source size by adding 10% overhead for other attributes that are associated with the source objects.
  total source size = source size x 1.10 =

__________________ KB
2. Product Objects
  • Estimate the average size of the product objects to be transferred.

    For example, if your project hierarchy contains several 500 KB product files and the remainder of the product files are 150 KB or smaller, you might choose 300 KB as a high (safe) estimate of the average product object size.

average product size = __________________ KB
  • Estimate the number of products in a regular transfer.

    For example, you might transfer five projects, each of which contains three product objects. If you expect an average of two products of each project to change between daily transfers, each transfer contains 10 product objects.

average number of products = __________________
  • If you are transferring objects with history, at least two objects are transferred for each object that has changed. Therefore, multiply the average number of products by a history factor that is equal to 1 if you are transferring without history, or 2 if you are transferring with history.
history factor = __________________ (1 or 2)
  • Estimate the product size.
product size = average product size x
average number of products x
history factor =

__________________ KB
  • Compute the total product size by adding 10% overhead for other attributes that are associated with the product objects.
    Note: You can allow much more than 10% overhead for attributes associated with product objects (for example, if you generate a Bills of Materials.
total product size = product size x 1.10 =

__________________ KB
3. Tasks
Multiply the number of tasks by 1 KB to estimate the space required for the average number of completed tasks in a transfer.
total task size = number of tasks x 1 KB =

__________________ KB
4. Folders
If folders are being transferred, assume that a folder with 50 tasks requires 1 KB of disk space. Divide the number of tasks by 50 and multiply by 1 KB to estimate the space required for the average number of folders in a transfer.
Note: Query-based folders increase in size over time. Consider this information in your estimate.

total folder size = number of tasks / 50 x 1 KB =

__________________ KB
5. Projects and Dependencies
  • Use the ccm export command to export each project object:

    ccm export /t export_directory /h project_name-version:project:dbid#1
  • Use the command of your choice (such as, dir in Windows or du -k in UNIX) to obtain the size (in kilobytes) of each export directory.
  export directory 1 size +
export directory 2 size +
export directory N size =


__________________ KB
6. Total size
Compute the total disk space required.
total size =
total source size +
total product size +
total task size +
total folder size +








__________________ KB
7. Total generate directory size
For the generate_directory, allocate at least 2.5 times the total size computed in Step 6.
total generate_directory size =


total size (Step 6) x 2.5

__________________ KB
If one transfer package is sent right after another (that is, if the transfers are queued), space must be allocated for each transfer package. Also, keep in mind that a failed transfer operation requires more disk space than a successful one.
8. Total receive directory size
For the receive_directory, allocate at least 2.0 times the total size computed in Step 6.
total receive_directory size =


total size (Step 6) x 2.0

__________________ KB
If one transfer package is received right after another (that is, if the receives are queued), disk space must be allocated for each transfer package. Also, keep in mind that a failed receive operation requires more disk space than a successful one.
Note: If a database is used for both the generate and receive operations, space must be available in its generate_directory and receive_directory.

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