honeymoose
/
OpenSearch
mirror of https://github.com/honeymoose/OpenSearch.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Tidied up the disk allocator docs

This commit is contained in:
Clinton Gormley 2017-07-06 12:16:53 +02:00
parent 407273f81d
commit ca12b1f2a6
1 changed files with 16 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
docs/reference/modules/cluster/disk_allocator.asciidoc
View File

@ -29,10 +29,11 @@ file or updated dynamically on a live cluster with the
the node.
`cluster.routing.allocation.disk.watermark.floodstage`::
Controls the floodstage watermark. It defaults to 95%, meaning ES enforce a read-only
+
--
Controls the floodstage watermark. It defaults to 95%, meaning ES enforces a read-only
index block (`index.blocks.read_only_allow_delete`) on every index that has
one or more shards allocated on the node that has at least on disk exceeding the floodstage.
one or more shards allocated on the node that has at least one disk exceeding the floodstage.
This is a last resort to prevent nodes from running out of disk space.
The index block must be released manually once there is enough disk space available
to allow indexing operations to continue.
@ -48,13 +49,7 @@ PUT /twitter/_settings
--------------------------------------------------
// CONSOLE
// TEST[setup:twitter]
NOTE: Percentage values refer to used disk space, while byte values refer to
free disk space. This can be confusing, since it flips the meaning of high and
low. For example, it makes sense to set the low watermark to 10gb and the high
watermark to 5gb, but not the other way around.
--
`cluster.info.update.interval`::
@ -72,9 +67,16 @@ watermark to 5gb, but not the other way around.
already used by the running relocation.
An example of updating the low watermark to no more than 80% of the disk size, a
high watermark of at least 50 gigabytes free, and updating the information about
the cluster every minute:
NOTE: Percentage values refer to used disk space, while byte values refer to
free disk space. This can be confusing, since it flips the meaning of high and
low. For example, it makes sense to set the low watermark to 10gb and the high
watermark to 5gb, but not the other way around.
An example of updating the low watermark to no more than 80% of the disk size,
a high watermark of at least 50 gigabytes free, and a floodstage watermark of
10 gigabytes free, and updating the information about the cluster every
minute:
[source,js]
--------------------------------------------------
@ -83,15 +85,10 @@ PUT _cluster/settings
"transient": {
"cluster.routing.allocation.disk.watermark.low": "80%",
"cluster.routing.allocation.disk.watermark.high": "50gb",
"cluster.routing.allocation.disk.watermark.floodstage": "10gb",
"cluster.info.update.interval": "1m"
}
}
--------------------------------------------------
// CONSOLE
NOTE: Prior to 2.0.0, when using multiple data paths, the disk threshold
decider only factored in the usage across all data paths (if you had two
data paths, one with 50b out of 100b free (50% used) and another with
40b out of 50b free (80% used) it would see the node's disk usage as 90b
out of 150b). In 2.0.0, the minimum and maximum disk usages are tracked
separately.