Force merge
Phases allowed: hot, warm.
Force merges the index into the specified maximum number of segments.
This action makes the index read-only.
To use the forcemerge
action in the hot
phase, the rollover
action must be present. If no rollover action is configured, ILM will reject the policy.
Options
max_num_segments
(Required, integer) Number of segments to merge to. To fully merge the index, set to 1
.
index_codec
(Optional, string) Codec used to compress the document store. The only accepted value is best_compression
, which uses DEFLATE for a higher compression ratio but slower stored fields performance. To use the default LZ4 codec, omit this argument.
If using best_compression
, ILM will close and then re-open the index prior to the force merge. While closed, the index will be unavailable for read or write operations.
Example
PUT _ilm/policy/my_policy
{
"policy": {
"phases": {
"warm": {
"actions": {
"forcemerge" : {
"max_num_segments": 1
}
}
}
}
}
}