Use the read-only replica

Prerequisite

The steps on this page assume you have logged into the target server The immediately upstream server for replica servers, edge servers, standby servers, proxies and brokers. See also 'upstream server' and 'central server'. named london as the P4 user with the access level of super. See Permission levels and access rights in the p4 protect topic of P4 CLI Reference. That user can have any name, but for convenience the examples use super:

p4 -u super login

Replica for reporting

You can perform all normal operations against the target server The immediately upstream server for replica servers, edge servers, standby servers, proxies and brokers. See also 'upstream server' and 'central server'., which in this example is named london:

p4 -p london:1666 command

To reduce the load on the target server, direct reporting (read-only) commands to the replica:

p4 -p replica:1667 command

Because the replica is running in -M readonly -D readonly mode, commands that read both metadata and depot file contents are available, and reporting commands (such as p4 annotate, p4 changes, p4 filelog, p4 diff2, p4 jobs) work normally. However, commands that update the server’s metadata or depot files are blocked.

Commands that update metadata

Some scenarios are relatively straightforward: consider a command such as p4 sync. A plain p4 sync fails, because whenever you sync your workspace, the P4 Server must update its metadata (the "have" list, which is stored in the db.have table). Instead, use p4 sync -p to populate a workspace without updating the have list:

p4 -u super -p replica:1667 sync -p //depot/project/...@1234

This operation succeeds because it does not update the server’s metadata.

Some commands affect metadata in more subtle ways. For example, many P4 Server commands update the last-update time that is associated with a specification (for example, a user or client specification). Attempting to use such commands on replica servers produces errors unless you use the -o option. For example, p4 client (which updates the Update: and Access fields of the client specification) fails:

p4 -u super -p replica:1667 client replica_client

Replica does not support this command.

However, p4 client -o works:

p4 -u super -p replica:1667 client -o replica_client

and the client spec is output to STDOUT.

If a command is blocked due to an implicit attempt to write to the server’s metadata, consider the options described above, as well as the broker.

Some commands, like p4 submit, always fail, because they attempt to write to the replica server’s depot files. These commands are blocked by the -D readonly option.)