This is an automated email from the ASF dual-hosted git repository.
gian pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/incubator-druid.git
The following commit(s) were added to refs/heads/master by this push:
new a88fbcd Improve caching doc (#7223)
a88fbcd is described below
commit a88fbcd5db5ea3c8283f3b4700cf14a8cfd168c1
Author: Pierre-Emile Ferron <[email protected]>
AuthorDate: Mon Mar 11 17:06:28 2019 -0700
Improve caching doc (#7223)
- Set correct default values for query context result cache parameters
- Add details about broker cache impact on local historical merging
---
docs/content/querying/caching.md | 4 ++--
docs/content/querying/query-context.md | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/docs/content/querying/caching.md b/docs/content/querying/caching.md
index c83d067..a1da2cb 100644
--- a/docs/content/querying/caching.md
+++ b/docs/content/querying/caching.md
@@ -35,8 +35,8 @@ can be enabled at either the Historical and Broker level (it
is not recommended
## Query caching on Brokers
Enabling caching on the Broker can yield faster results than if query caches
were enabled on Historicals for small clusters. This is
-the recommended setup for smaller production clusters (< 20 servers). Take
note that when caching is enabled on the Broker,
-results from Historicals are returned on a per segment basis, and Historicals
will not be able to do any local result merging.
+the recommended setup for smaller production clusters (< 20 servers). Take
note that when `druid.broker.cache.populateCache` is set to
+`true`, results from Historicals are returned on a per segment basis, and
Historicals will not be able to do any local result merging.
Result level caching is enabled only on the Broker side.
## Query caching on Historicals
diff --git a/docs/content/querying/query-context.md
b/docs/content/querying/query-context.md
index 185ae2d..ef730f3 100644
--- a/docs/content/querying/query-context.md
+++ b/docs/content/querying/query-context.md
@@ -33,8 +33,8 @@ The query context is used for various query configuration
parameters. The follow
|queryId | auto-generated | Unique identifier
given to this query. If a query ID is set or known, this can be used to cancel
the query |
|useCache | `true` | Flag indicating
whether to leverage the query cache for this query. When set to false, it
disables reading from the query cache for this query. When set to true, Druid
uses druid.broker.cache.useCache or druid.historical.cache.useCache to
determine whether or not to read from the query cache |
|populateCache | `true` | Flag indicating
whether to save the results of the query to the query cache. Primarily used for
debugging. When set to false, it disables saving the results of this query to
the query cache. When set to true, Druid uses druid.broker.cache.populateCache
or druid.historical.cache.populateCache to determine whether or not to save the
results of this query to the query cache |
-|useResultLevelCache | `false` | Flag
indicating whether to leverage the result level cache for this query. When set
to false, it disables reading from the query cache for this query. When set to
true, Druid uses druid.broker.cache.useResultLevelCache to determine whether or
not to read from the query cache |
-|populateResultLevelCache | `false` | Flag
indicating whether to save the results of the query to the result level cache.
Primarily used for debugging. When set to false, it disables saving the results
of this query to the query cache. When set to true, Druid uses
druid.broker.cache.populateCache to determine whether or not to save the
results of this query to the query cache |
+|useResultLevelCache | `true` | Flag indicating
whether to leverage the result level cache for this query. When set to false,
it disables reading from the query cache for this query. When set to true,
Druid uses druid.broker.cache.useResultLevelCache to determine whether or not
to read from the query cache |
+|populateResultLevelCache | `true` | Flag indicating
whether to save the results of the query to the result level cache. Primarily
used for debugging. When set to false, it disables saving the results of this
query to the query cache. When set to true, Druid uses
druid.broker.cache.populateCache to determine whether or not to save the
results of this query to the query cache |
|bySegment | `false` | Return "by
segment" results. Primarily used for debugging, setting it to `true` returns
results associated with the data segment they came from |
|finalize | `true` | Flag indicating
whether to "finalize" aggregation results. Primarily used for debugging. For
instance, the `hyperUnique` aggregator will return the full HyperLogLog sketch
instead of the estimated cardinality when this flag is set to `false` |
|chunkPeriod | `P0D` (off) | At the Broker
process level, long interval queries (of any type) may be broken into shorter
interval queries to parallelize merging more than normal. Broken up queries
will use a larger share of cluster resources, but, if you use groupBy "v1, it
may be able to complete faster as a result. Use ISO 8601 periods. For example,
if this property is set to `P1M` (one month), then a query covering a year
would be broken into 12 smaller [...]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
