Inspection of the code revealed some other local variables that could overflow with large messages. This patch takes two approaches to eliminate the issues. First, it limits the total size of the messages by limiting the total size of the sidecars to INT_MAX. The total size of the protobuf and header components of the message should be considerably smaller, so limiting the sidecars to INT_MAX eliminates messages that are larger than UINT_MAX. This also means that the sidecar offsets, which are unsigned 32-bit integers, are also safe. Given that FLAGS_rpc_max_message_size is limited to INT_MAX at startup, the receiver would reject any message this large anyway. This also helps with the networking codepath, as any given sidecar will have a size less than INT_MAX, so every Slice that interacts with Writev() is shorter than INT_MAX. Second, even with sidecars limited to INT_MAX, the headers and protobuf parts of the messages mean that certain messages could still exceed INT_MAX. This patch changes some of the sockets codepath to tolerate iovec's that reference more than INT_MAX bytes total. Specifically, it changes Writev()'s nwritten bytes to an int64_t for both TlsSocket and Socket. TlsSocket works because it is sending each Slice individually. The first change limited any given Slice to INT_MAX, so each individual Write() should not be impacted. For Socket, Writev() uses sendmsg(). It should do partial network sends to handle this case. Any Write() call specifies its size with a 32-bit integer, and that will not be impacted by this patch. Testing: - Modified TestRpcSidecarLimits() to verify that sidecars are limited to INT_MAX bytes. - Added a test mode to TestRpcSidecarLimits() where it overrides rpc_max_message_size and sends the maximal message. This verifies that the client send codepath can handle the maximal message. Reviewed-on: http://gerrit.cloudera.org:8080/9601 Reviewed-by: Todd Lipcon <todd@apache.org> Tested-by: Todd Lipcon <todd@apache.org> Changes from Kudu version: - Updated declaration of FLAGS_rpc_max_message_size in rpc-mgr.cc and added a warning not to set it larger than INT_MAX. Change-Id: I469feff940fdd07e1e407c9df49de79ed303151e Reviewed-on: http://gerrit.cloudera.org:8080/9748 Reviewed-by: Michael Ho <kwho@cloudera.com> Tested-by: Impala Public Jenkins
Welcome to Impala
Lightning-fast, distributed SQL queries for petabytes of data stored in Apache Hadoop clusters.
Impala is a modern, massively-distributed, massively-parallel, C++ query engine that lets you analyze, transform and combine data from a variety of data sources:
- Best of breed performance and scalability.
- Support for data stored in HDFS, Apache HBase and Amazon S3.
- Wide analytic SQL support, including window functions and subqueries.
- On-the-fly code generation using LLVM to generate CPU-efficient code tailored specifically to each individual query.
- Support for the most commonly-used Hadoop file formats, including the Apache Parquet project.
- Apache-licensed, 100% open source.
More about Impala
To learn more about Impala as a business user, or to try Impala live or in a VM, please visit the Impala homepage.
If you are interested in contributing to Impala as a developer, or learning more about Impala's internals and architecture, visit the Impala wiki.
Supported Platforms
Impala only supports Linux at the moment.
Export Control Notice
This distribution uses cryptographic software and may be subject to export controls. Please refer to EXPORT_CONTROL.md for more information.
Build Instructions
See bin/bootstrap_build.sh.
Detailed Build Notes
Impala can be built with pre-built components, downloaded from S3, or can be built with an in-place toolchain located in the thirdparty directory (not recommended). The components needed to build Impala are Apache Hadoop, Hive, HBase, and Sentry. If you need to manually override the locations or versions of these components, you can do so through the environment variables and scripts listed below.
Scripts and directories
| Location | Purpose |
|---|---|
| bin/impala-config.sh | This script must be sourced to setup all environment variables properly to allow other scripts to work |
| bin/impala-config-local.sh | A script can be created in this location to set local overrides for any environment variables |
| bin/impala-config-branch.sh | A version of the above that can be checked into a branch for convenience. |
| bin/bootstrap_build.sh | A helper script to bootstrap some of the build requirements. |
| bin/bootstrap_development.sh | A helper script to bootstrap a developer environment. Please read it before using. |
| be/build/ | Impala build output goes here. |
| be/generated-sources/ | Thrift and other generated source will be found here. |
Build Related Variables
| Environment variable | Default value | Description |
|---|---|---|
| IMPALA_HOME | Top level Impala directory | |
| IMPALA_TOOLCHAIN | "${IMPALA_HOME}/toolchain" | Native toolchain directory (for compilers, libraries, etc.) |
| SKIP_TOOLCHAIN_BOOTSTRAP | "false" | Skips downloading the toolchain any python dependencies if "true" |
| CDH_COMPONENTS_HOME | "${IMPALA_HOME}/toolchain/cdh_components" OR "${IMPALA_HOME}/thirdparty" (if detected) | If a thirdparty directory is present, components found here will override anything in IMPALA_TOOLCHAIN. |
| CDH_MAJOR_VERSION | "5" | Identifier used to uniqueify paths for potentially incompatible component builds. |
| IMPALA_CONFIG_SOURCED | "1" | Set by ${IMPALA_HOME}/bin/impala-config.sh (internal use) |
| JAVA_HOME | "/usr/lib/jvm/${JAVA_VERSION}" | Used to locate Java |
| JAVA_VERSION | "java-7-oracle-amd64" | Can override to set a local Java version. |
| JAVA | "${JAVA_HOME}/bin/java" | Java binary location. |
| CLASSPATH | See bin/set-classpath.sh for details. | |
| PYTHONPATH | Will be changed to include: "${IMPALA_HOME}/shell/gen-py" "${IMPALA_HOME}/testdata" "${THRIFT_HOME}/python/lib/python2.7/site-packages" "${HIVE_HOME}/lib/py" "${IMPALA_HOME}/shell/ext-py/prettytable-0.7.1/dist/prettytable-0.7.1" "${IMPALA_HOME}/shell/ext-py/sasl-0.1.1/dist/sasl-0.1.1-py2.7-linux-x "${IMPALA_HOME}/shell/ext-py/sqlparse-0.1.14/dist/sqlparse-0.1.14-py2 |
Source Directories for Impala
| Environment variable | Default value | Description |
|---|---|---|
| IMPALA_BE_DIR | "${IMPALA_HOME}/be" | Backend directory. Build output is also stored here. |
| IMPALA_FE_DIR | "${IMPALA_HOME}/fe" | Frontend directory |
| IMPALA_COMMON_DIR | "${IMPALA_HOME}/common" | Common code (thrift, function registry) |
Various Compilation Settings
| Environment variable | Default value | Description |
|---|---|---|
| IMPALA_BUILD_THREADS | "8" or set to number of processors by default. | Used for make -j and distcc -j settings. |
| IMPALA_MAKE_FLAGS | "" | Any extra settings to pass to make. Also used when copying udfs / udas into HDFS. |
| USE_SYSTEM_GCC | "0" | If set to any other value, directs cmake to not set GCC_ROOT, CMAKE_C_COMPILER, CMAKE_CXX_COMPILER, as well as setting TOOLCHAIN_LINK_FLAGS |
| IMPALA_CXX_COMPILER | "default" | Used by cmake (cmake_modules/toolchain and clang_toolchain.cmake) to select gcc / clang |
| USE_GOLD_LINKER | "true" | Directs backend cmake to use gold. |
| IS_OSX | "false" | (Experimental) currently only used to disable Kudu. |
Dependencies
| Environment variable | Default value | Description |
|---|---|---|
| HADOOP_HOME | "${CDH_COMPONENTS_HOME}/hadoop-${IMPALA_HADOOP_VERSION}/" | Used to locate Hadoop |
| HADOOP_INCLUDE_DIR | "${HADOOP_HOME}/include" | For 'hdfs.h' |
| HADOOP_LIB_DIR | "${HADOOP_HOME}/lib" | For 'libhdfs.a' or 'libhdfs.so' |
| HIVE_HOME | "${CDH_COMPONENTS_HOME}/{hive-${IMPALA_HIVE_VERSION}/" | |
| HIVE_SRC_DIR | "${HIVE_HOME}/src" | Used to find Hive thrift files. |
| HBASE_HOME | "${CDH_COMPONENTS_HOME}/hbase-${IMPALA_HBASE_VERSION}/" | |
| SENTRY_HOME | "${CDH_COMPONENTS_HOME}/sentry-${IMPALA_SENTRY_VERSION}/" | Used to setup test data |
| THRIFT_HOME | "${IMPALA_TOOLCHAIN}/thrift-${IMPALA_THRIFT_VERSION}" |