[DOCS] A number of typos were fixed in impala_dedicated_coordinator Change-Id: I5758a5beabdf46feaf52fa0b3ed14bdce4408754 Reviewed-on: http://gerrit.cloudera.org:8080/11986 Reviewed-by: Alex Rodoni <[email protected]> Tested-by: Impala Public Jenkins <[email protected]>
Project: http://git-wip-us.apache.org/repos/asf/impala/repo Commit: http://git-wip-us.apache.org/repos/asf/impala/commit/fcfabe0f Tree: http://git-wip-us.apache.org/repos/asf/impala/tree/fcfabe0f Diff: http://git-wip-us.apache.org/repos/asf/impala/diff/fcfabe0f Branch: refs/heads/master Commit: fcfabe0f5c38a4e37d52d14a1010b02ae2973afb Parents: e421223 Author: Alex Rodoni <[email protected]> Authored: Mon Nov 26 11:49:28 2018 -0800 Committer: Alex Rodoni <[email protected]> Committed: Mon Nov 26 20:04:24 2018 +0000 ---------------------------------------------------------------------- docs/topics/impala_dedicated_coordinator.xml | 54 ++++++++++++----------- 1 file changed, 28 insertions(+), 26 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/impala/blob/fcfabe0f/docs/topics/impala_dedicated_coordinator.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_dedicated_coordinator.xml b/docs/topics/impala_dedicated_coordinator.xml index 1b43772..73aa2cf 100644 --- a/docs/topics/impala_dedicated_coordinator.xml +++ b/docs/topics/impala_dedicated_coordinator.xml @@ -165,13 +165,13 @@ under the License. <li > <p> - Provides a better concurrency by avoiding coordinator bottleneck. + Provides better concurrency by avoiding coordinator bottleneck. </p> </li> <li> <p> - Eliminates the query over admission by using one dedicated coordinator. + Eliminates query over-admission. </p> </li> @@ -185,7 +185,7 @@ under the License. <li > <p> Improves reliability and performance for highly concurrent workloads by reducing - workload stress on coordinators. Dedicated coordinators require 50% or less + workload stress on coordinators. Dedicated coordinators require 50% or fewer connections and threads. </p> </li> @@ -228,7 +228,7 @@ under the License. <p> To maintain a healthy state and optimal performance, it is recommended that you keep the peak utilization of all resources used by Impala, including CPU, the number of threads, - the number of connections, RPCs, under 80%. + the number of connections, and RPCs, under 80%. </p> <p > @@ -337,9 +337,9 @@ under the License. On a large cluster with 50+ nodes, the number of network connections from a coordinator to executors can grow quickly as query complexity increases. The growth is much greater on coordinators than executors. Add a few more coordinators - if workload are complex, i.e. (an average number of fragments * number of Impalad) - > 500, but with the low memory/CPU usage to share the load. Watch IMPALA-4603 and - IMPALA-7213 to track the progress on fixing this issue. + if workloads are complex, i.e. (an average number of fragments * number of + Impalad) > 500, but with the low memory/CPU usage to share the load. Watch + IMPALA-4603 and IMPALA-7213 to track the progress on fixing this issue. </li> <li > @@ -352,7 +352,7 @@ under the License. <li> The front-end connection requirement is not a factor in determining the number of dedicated coordinators. Consider setting up a connection pool at the client side - instead of adding coordinators. For a short term solution, you could increase the + instead of adding coordinators. For a short-term solution, you could increase the value of <codeph>fe_service_threads</codeph> on coordinators to allow more client connections. </li> @@ -591,33 +591,35 @@ under the License. <li > <p> - <b>(Dedicated) Executors: </b>They should be collocated with DataNodes as usual. - The number of hosts with this setting typically increases as the cluster grows - larger and handles more table partitions, data files, and concurrent queries. + <b>(Dedicated) Executors: </b>They should be collocated with DataNodes as usual. The + number of hosts with this setting typically increases as the cluster grows larger + and handles more table partitions, data files, and concurrent queries. </p> </li> </ul> - <p> To configuring dedicated coordinators/executors, you specify one of - the following startup flags for the <cmdname>impalad</cmdname> daemon on - each host: <ul> + <p> + To configuring dedicated coordinators/executors, you specify one of the following + startup flags for the <cmdname>impalad</cmdname> daemon on each host: + <ul> <li> <p> - <codeph>is_executor=false</codeph> for each host that does not act - as an executor for Impala queries. These hosts act exclusively as - query coordinators. This setting typically applies to a relatively - small number of hosts, because the most common topology is to have - nearly all DataNodes doing work for query execution. </p> + <codeph>is_executor=false</codeph> for each host that does not act as an executor + for Impala queries. These hosts act exclusively as query coordinators. This + setting typically applies to a relatively small number of hosts, because the most + common topology is to have nearly all DataNodes doing work for query execution. + </p> </li> + <li> <p> - <codeph>is_coordinator=false</codeph> for each host that does not - act as a coordinator for Impala queries. These hosts act - exclusively as executors. The number of hosts with this setting - typically increases as the cluster grows larger and handles more - table partitions, data files, and concurrent queries. As the - overhead for query coordination increases, it becomes more - important to centralize that work on dedicated hosts. </p> + <codeph>is_coordinator=false</codeph> for each host that does not act as a + coordinator for Impala queries. These hosts act exclusively as executors. The + number of hosts with this setting typically increases as the cluster grows larger + and handles more table partitions, data files, and concurrent queries. As the + overhead for query coordination increases, it becomes more important to centralize + that work on dedicated hosts. + </p> </li> </ul> </p>
