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Posted to commits@impala.apache.org by ar...@apache.org on 2019/07/03 20:24:19 UTC
[impala] 02/02: IMPALA-8427: [DOCS] Document the new startup flag
IMPALA-7800 introduced
This is an automated email from the ASF dual-hosted git repository.
arodoni pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/impala.git
commit 19430082f34ae69c86dd3cd6078f8855e9e8646d
Author: Alex Rodoni <ar...@cloudera.com>
AuthorDate: Fri Jun 28 13:24:34 2019 -0700
IMPALA-8427: [DOCS] Document the new startup flag IMPALA-7800 introduced
- Added a new doc impala_client.xml as the overview of Impala impala
client access.
Change-Id: I1a4c1975721c32a78a003d91babc5d2bb90f3949
Reviewed-on: http://gerrit.cloudera.org:8080/13762
Tested-by: Impala Public Jenkins <im...@cloudera.com>
Reviewed-by: Michael Ho <kw...@cloudera.com>
---
docs/impala.ditamap | 19 +++--
docs/topics/impala_client.xml | 142 ++++++++++++++++++++++++++++++++++
docs/topics/impala_config_options.xml | 47 -----------
3 files changed, 153 insertions(+), 55 deletions(-)
diff --git a/docs/impala.ditamap b/docs/impala.ditamap
index 554430f..306263f 100644
--- a/docs/impala.ditamap
+++ b/docs/impala.ditamap
@@ -56,8 +56,6 @@ under the License.
</topicref>
<topicref audience="standalone" href="topics/impala_config.xml">
<topicref href="topics/impala_config_performance.xml"/>
- <topicref href="topics/impala_odbc.xml"/>
- <topicref href="topics/impala_jdbc.xml"/>
</topicref>
<topicref audience="standalone" href="topics/impala_upgrading.xml"/>
<topicref audience="standalone" href="topics/impala_processes.xml">
@@ -277,12 +275,7 @@ under the License.
<topicref href="topics/impala_langref_unsupported.xml"/>
<topicref href="topics/impala_porting.xml"/>
</topicref>
- <topicref href="topics/impala_impala_shell.xml">
- <topicref href="topics/impala_shell_options.xml"/>
- <topicref href="topics/impala_connecting.xml"/>
- <topicref href="topics/impala_shell_running_commands.xml"/>
- <topicref href="topics/impala_shell_commands.xml"/>
- </topicref>
+
<topicref href="topics/impala_performance.xml">
<topicref href="topics/impala_perf_cookbook.xml"/>
<topicref href="topics/impala_perf_joins.xml"/>
@@ -320,6 +313,16 @@ under the License.
<topicref rev="2.9.0" href="topics/impala_adls.xml"/>
<topicref href="topics/impala_isilon.xml"/>
<topicref href="topics/impala_logging.xml"/>
+ <topicref href="topics/impala_client.xml">
+ <topicref href="topics/impala_impala_shell.xml">
+ <topicref href="topics/impala_shell_options.xml"/>
+ <topicref href="topics/impala_connecting.xml"/>
+ <topicref href="topics/impala_shell_running_commands.xml"/>
+ <topicref href="topics/impala_shell_commands.xml"/>
+ </topicref>
+ <topicref href="topics/impala_odbc.xml"/>
+ <topicref href="topics/impala_jdbc.xml"/>
+ </topicref>
<topicref href="topics/impala_troubleshooting.xml">
<topicref href="topics/impala_webui.xml"/>
<topicref href="topics/impala_breakpad.xml"/>
diff --git a/docs/topics/impala_client.xml b/docs/topics/impala_client.xml
new file mode 100644
index 0000000..93987e1
--- /dev/null
+++ b/docs/topics/impala_client.xml
@@ -0,0 +1,142 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership. The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
+<concept id="intro_client">
+
+ <title>Impala Client Access</title>
+
+ <conbody>
+
+ <p>
+ Application developers have a number of options to interface with Impala. The core
+ development language with Impala is SQL. You can also use Java or other languages to
+ interact with Impala through the standard JDBC and ODBC interfaces used by many business
+ intelligence tools. For specialized kinds of analysis, you can supplement the Impala
+ built-in functions by writing user-defined functions in C++ or Java.
+ </p>
+
+ <p>
+ You can connect and submit requests to the Impala through:
+ </p>
+
+ <ul>
+ <li>
+ The impala-shell interactive command interpreter
+ </li>
+
+ <li>
+ The Hue web-based user interface
+ </li>
+
+ <li>
+ JDBC
+ </li>
+
+ <li>
+ ODBC
+ </li>
+ </ul>
+
+ <p>
+ Each <codeph>impalad</codeph> daemon process, running on separate nodes in a cluster,
+ listens to <xref href="impala_ports.xml#ports">several ports</xref> for incoming requests:
+ </p>
+
+ <ul>
+ <li>
+ Requests from <codeph>impala-shell</codeph> and Hue are routed to the
+ <codeph>impalad</codeph> daemons through the same port.
+ </li>
+
+ <li>
+ The <codeph>impalad</codeph> daemons listen on separate ports for JDBC and ODBC
+ requests.
+ </li>
+ </ul>
+
+ <section id="section_egg_wjt_f3b">
+
+ <title>Impala Startup Options for Client Connections</title>
+
+ <p>
+ The following options control client connections to Impala.
+ </p>
+
+ <dl>
+ <dlentry>
+
+ <dt>
+ --fe_service_threads
+ </dt>
+
+ <dd>
+ Specifies the maximum number of concurrent client connections allowed. The default
+ value is 64 with which 64 queries can run simultaneously.
+ <p>
+ If you have more clients trying to connect to Impala than the value of this
+ setting, the later arriving clients have to wait for the duration specified by
+ <codeph>--accepted_client_cnxn_timeout</codeph>. You can increase this value to
+ allow more client connections. However, a large value means more threads to be
+ maintained even if most of the connections are idle, and it could negatively
+ impact query latency. Client applications should use the connection pool to avoid
+ need for large number of sessions.
+ </p>
+ </dd>
+
+ </dlentry>
+
+ <dlentry>
+
+ <dt>
+ --accepted_client_cnxn_timeout
+ </dt>
+
+ <dd>
+ Controls how Impala treats new connection requests if it has run out of the number
+ of threads configured by <codeph>--fe_service_threads</codeph>.
+ <p>
+ If <codeph>--accepted_client_cnxn_timeout > 0</codeph>, new connection requests
+ are rejected if Impala can't get a server thread within the specified (in seconds)
+ timeout.
+ </p>
+
+ <p>
+ If <codeph>--accepted_client_cnxn_timeout=0</codeph>, i.e. no timeout, clients
+ wait indefinitely to open the new session until more threads are available.
+ </p>
+
+ <p>
+ The default timeout is 5 minutes.
+ </p>
+
+ <p>
+ The timeout applies only to client facing thrift servers, i.e., HS2 and Beeswax
+ servers.
+ </p>
+ </dd>
+
+ </dlentry>
+ </dl>
+
+ </section>
+
+ </conbody>
+
+</concept>
diff --git a/docs/topics/impala_config_options.xml b/docs/topics/impala_config_options.xml
index 469fa62..7ef6612 100644
--- a/docs/topics/impala_config_options.xml
+++ b/docs/topics/impala_config_options.xml
@@ -294,53 +294,6 @@ Starting Impala Catalog Server: [ OK ]</codeblock>
</concept>
- <concept id="config_options_impalad">
-
- <title>Startup Options for impalad Daemon</title>
-
- <conbody>
-
- <p>
- The <codeph>impalad</codeph> daemon implements the main Impala service, which performs
- query processing and reads from and writes to the data files. Some of the noteworthy
- options are:
- <ul>
- <li>
- The <codeph>‑‑fe_service_threads</codeph> option specifies the maximum
- number of concurrent client connections allowed. The default value is 64 with which
- 64 queries can run simultaneously.
- <p>
- If you have more clients trying to connect to Impala than the value of this
- setting, the later arriving clients have to wait until previous clients
- disconnect. You can increase this value to allow more client connections. However,
- a large value means more threads to be maintained even if most of the connections
- are idle, and it could negatively impact query latency. Client applications should
- use the connection pool to avoid need for large number of sessions.
- </p>
- </li>
- </ul>
- </p>
-
- </conbody>
-
- </concept>
-
- <concept id="config_options_statestored">
-
- <title>Startup Options for statestored Daemon</title>
-
- <conbody>
-
- <p>
- The <cmdname>statestored</cmdname> daemon implements the Impala StateStore service,
- which monitors the availability of Impala services across the cluster, and handles
- situations such as nodes becoming unavailable or becoming available again.
- </p>
-
- </conbody>
-
- </concept>
-
<concept rev="1.2" id="config_options_catalogd">
<title>Startup Options for catalogd Daemon</title>