The URL
/admin/dataDomainName?op=merge command
can also be used to force a merge.
Manually
forcing a merge is considered a one-time version, because after the merge
operation is performed (via a temporary
aggressive change to the merge policy), the merge policy
reverts to its previous setting.
The one-time version of the
merge command is used to perform a complete merge of
all generations without making a change to the default merge policy.
Forcing a merge implies starting a full merge of all generations of
index files. When running this command, be aware of the following
considerations:
- Memory requirements. Forcing
a complete merge utilizes the server's memory. If the amount of memory reaches
the amount of RAM that is available, the merge operation will continue to work,
but could run substantially slower and have a higher impact on query
performance.
- Disk space requirements.
Forcing a merge requires provisioning three times the amount of disk space as
the current size of the index files for the particular data domain. If not
enough disk space is provisioned, it could be disruptive to force a complete
merge. This consideration is especially important for running this command on
the Oracle Endeca Server in a production environment.
In an Endeca Server cluster hosting a data domain cluster, when you
issue this command for the data domain, it is routed to the leader Dgraph node
for the data domain.
The format of the one-time version of the command is:
/admin/dataDomainName?op=merge&mergepolicy=<version>
The following example assumes that the Dgraph process of the data domain
is using a balanced merge policy, and that you want to temporarily apply an
aggressive policy so that the merging can be performed:
http://web007:7001/endeca-server/admin/books?op=merge&mergepolicy=aggressive
When you issue the command, the Dgraph process starts a manual merge of
its index files. After the merging is performed, the merge policy reverts to
its previous setting.