Intel® SDK for OpenCL* Applications XE 2013 Release Notes

Contents:

Introduction
What's New
System Requirements
Installation Notes
Resolved Issues
Issues and Limitations

Introduction

The Intel® SDK for OpenCL* Applications XE 2013 provides certified OpenCL 1.2 support for Intel Xeon® processors and Intel Xeon Phi™ coprocessors on Linux* operating systems. This version of the SDK is targeted at developers of highly parallel applications including High Performance Compute (HPC), workstations, and data analytics, to name just a few. The SDK includes tools, optimization guides, and training to develop and optimized OpenCL applications.

This document contains information about the new features, system requirements, installation instructions, limitations and known issues.

What's New

In this release

• OpenCL 1.2 full profile features (conformant) across both Intel Xeon processor and Intel Xeon Phi™ coprocessor
• Multi Intel Xeon Phi coprocessors support on the same system
• Additional performance through:
• Task scheduling improvements
• Auto data prefetching improvements
• Implicit vectorization improvements
• Faster host/device data transfer

More features, also available in Beta release

• New Intel SDK for OpenCL Applications XE packages for Linux* OS
• Single OpenCL* platform for Intel CPU and  coprocessor
• Platform version (CL_PLATFORM_VERSION) – OpenCL*  1.2
• Intel Xeon processor device version (CL_DEVICE_VERSION) – OpenCL*  1.2
• Intel Xeon Phi coprocessor device version (CL_DEVICE_VERSION) – OpenCL*  1.2
• Intel Xeon processor device type – CL_DEVICE_TYPE_CPU
• Intel Xeon Phi coprocessor device type - CL_DEVICE_TYPE_ACCELERATOR
• Platform name – Intel OpenCL*
• Support for Red Hat Enterprise Linux* OS 6.1 and SUSE Linux Enterprise Server* 11.1
• OpenCL 1.2 KHR extensions and optional features. See full list in the product User’s Guide, available at  http://software.intel.com/en-us/vcsource/tools/opencl-sdk-xe/.
• Intel SDK for OpenCL Applications – Kernel Builder and Offline Complier (64-bit version).
• OpenCL kernel debugging for CPU on Linux* OS with the GNU Project Debugger (GDB).
• Support for the CPU device is fully compatible with the CPU device support in the accompanied Intel SDK for OpenCL Applications 2013 for Windows* OS.  
• Intel Xeon Phi coprocessor OpenCL device is available with an installed coprocessor device on the system.

System Requirements

Supported Hardware

This SDK is tested on the following processors:

• Intel Xeon Phi coprocessor 5110P
• Intel Xeon Processor E5 Family
• Intel Xeon Processor E7 Family

NOTE:

Incompatible or proprietary instructions in non-Intel processors may cause the analysis capabilities of this product to function incorrectly. Any attempt to analyze code not supported by Intel processors may lead to failures in this product.

Supported Operating Systems

Intel SDK for OpenCL Applications XE 2013 supports the following operating systems:  

• Red Hat Enterprise Linux OS 6.0 or higher (64-bit version)
• SUSE  Linux Enterprise Server 11.1 or higher (64-bit version)

Due to possible Intel AVX issues with the default glibc 2.11.1 implementation, the Intel SDK for OpenCL Applications XE 2013 libraries might require glibc-2.12-1.47 Refer to the OS documentation for more information.

Installation Notes for Linux* OS

Intel SDK for OpenCL* Applications XE 2013 provides the following installation packages:

-       Intel SDK for OpenCL Application XE 2013 – Runtime Only Package - This package provides support for OpenCL 1.2 features on Intel Xeon processors and Intel Xeon Phi coprocessors. This package contains the OpenCL runtime and compiler for Linux operating systems

-       Intel SDK for OpenCL Application XE 2013 package - This package is a comprehensive software development kit for OpenCL* applications on Intel Xeon processors and Intel Xeon Phi coprocessors. The package contains OpenCL* C header files, which enable development of OpenCL applications in C and/or C++ language, development tools and. This package also includes the Intel SDK for OpenCL Application XE 2013– runtime only package.

Installation of the Intel SDK for OpenCL* Applications XE

Installation Prerequisites

All RPM (RPM Package Manager) packages of Intel SDK for OpenCL Applications are digitally signed.

Verify signature of each RPM package after downloading.

To verify signatures, do the following:

1. Download the public key from the download page of the product.

2. Import public key into rpm database by use of the following command:

            sudo rpm --import Intel-E901-172E-EF96-900F-B8E1-4184-D7BE-0E73-F789-186F.pub

3. Verify signature of RPM package:

# rpm --checksig <rpm name>.rpm

where <rpm name> is the name of the RPM package.

            Expected output for RPM with valid digital signature is:

            <rpm name>.rpm: rsa sha1 (md5) pgp md5 OK

For IntelXeon Phicoprocessor device support, you must install the latest version of Intel Manycore Platform Software Stack (IntelMPSS) available at http://software.intel.com/en-us/articles/intel-manycore-platform-software-stack-mpss

Intel SDK for OpenCL Applications XE 2013 installation packaged are delivered in the form of archives containing RPM packages with wrappers for ease of installation/uninstallation procedures. You can use any of the approaches (use wrappers or directly rpm packages) depending on your preferences.

Installing the Product Using Shell Scripts

Download the relevant installation package and extract the TGZ archive contents:

# tar xzf intel_sdk_for_ocl_applications_2013_xe_gold_TYPE_VERSION_x64.tgz

# cd intel_sdk_for_ocl_applications_2013_xe_gold_TYPE_VERSION_x64

NOTE:

Before installing the Intel SDK for OpenCL Applications XE 2013 on the Linux* operating systems, remove previous installations of the SDK, older than 2013 XE Beta. You must have root permissions to successfully install the product.

To install only the CPU runtime, run the following command:

            # sudo ./install-cpu.sh

To install the CPU and Intel Xeon Phi coprocessor runtime, run the following command:

            # sudo ./install-cpu+mic.sh

NOTE:

Installing the CPU and Intel Xeon Phi coprocessor runtime using scripts without prior uninstallation of the CPU-only runtime is not supported.

Installing the Product Using RPM Package Manager

Intel SDK for OpenCL Applications XE 2013 installation package can also be installed directly through the rpm packages. The list of the RMP packages includes:

-       opencl-1.2-base– package contains OpenCL installable client driver loader. The OpenCL Installable Client Driver (ICD) enables different OpenCL implementations to coexist on the same system. ICD also enables applications to select between OpenCL implementations at run time.

-       opencl-1.2-intel-cpu – package contains the OpenCL runtime and compiler, which enable Intel(R) CPU as an OpenCL device. OpenCL 1.2 features are supported on all generations of the Intel(R) Core(tm) processors and the Intel Xeon processors.

-       opencl-1.2-intel-mic - package contains the OpenCL runtime that enables the advantages of the Intel Xeon Phi coprocessor as an OpenCL device. Intel Manycore Platform Software Stack (Intel MPSS) is required for the Intel Xeon Phi coprocessor support on Linux OS.

-       opencl-1.2-devel– package contains OpenCL C header files, which enable development of OpenCL applications on your machine.

-       opencl-1.2-intel-devel– package contains the following Intel SDK for OpenCL Applications Development Tools:

• Intel SDK for OpenCL - Kernel Builder, which enables building and analyzing OpenCL kernels, and provides full offline OpenCL language compilation.
• Intel SDK for OpenCL - Offline Compiler, a command-line utility, which enables offline compilation, and building of OpenCL kernels.

To install Intel SDK for OpenCL Applications XE 2013 using RPM Package Manager:

1. Download the relevant installation package and extract the TGZ archive contents:

For SDK package:

          # tar xzf intel_sdk_for_ocl_applications_2013_xe_sdk_[VERSION]_x64.tgz

          # cd intel_sdk_for_ocl_applications_2013_xe_sdk_[VERSION]_x64

            For the runtime only package:

          # tar xzf intel_sdk_for_ocl_applications_2013_xe_runtime_[VERSION]x64.tgz

          # cd intel_sdk_for_ocl_applications_2013_xe_runtime_[VERSION]x64

1. To install the CPU-only runtime, run the following commands:

On RedHat Enterprise Linux OS:

                        # sudo yum install *base*.rpm *intel-cpu*.rpm

On SUSE Linux Enterprise Server OS:

                        # sudo zypper install *base*.rpm *intel-cpu*.rpm

To install the CPU and Intel Xeon Phi coprocessor support, run following commands:

On RedHat Enterprise Linux OS:

                        # sudo yum install *base*.rpm *intel-cpu*.rpm *intel-mic*.rpm

On SUSE Linux Enterprise Server OS:

                        # sudo zypper install *base*.rpm *intel-cpu*.rpm *intel-mic*.rpm

NOTE:

If the CPU-only runtime is already installed, the installation of the CPU and the Intel Xeon Phi coprocessor runtime adds the Intel Xeon Phi coprocessor support without removing the CPU runtime.

NOTE:

If you encounter a message saying that libcoi_host.so.0()(64bit) or libcoi_host.so.0(COI_1.0)(64bit) is needed, install the Intel MPSS.

To install the development tools, run the following commands:

On RedHat Enterprise Linux OS:

                        # sudo yum install *base*.rpm *intel-cpu*.rpm *devel*.rpm

On SUSE Linux Enterprise Server OS:

                        # sudo zypper install *base*.rpm *intel-cpu*.rpm *devel*.rpm

NOTE:

In case of SDK installation on a machine without runtime components, the CPU-only runtime is installed together with the tool set.

Upgrading Intel SDK for OpenCL* Applications XE (From Beta Version)

To upgrade the product please:

1. Follow the instructions on “Installation Prerequisites” and upgrade the Intel MPSS package.
2. Follow the instructions on “Installing the Product Using RPM Package Manager” chapter.

NOTE:

You can only upgrade the Intel SDK for OpenCL Applications XE 2013 Beta. Direct upgrade of an older version of the product is not supported.

Code developed with the Beta version is expected to run with the production version without any changes.

To upgrade an older version of the SDK, first uninstall it, and then install the Intel SDK for OpenCL Applications XE 2013.

Uninstalling Intel SDK for OpenCL* Applications XE

To uninstall the product using the uninstallation script, do the following:

1. Go to the folder to which you extracted the TGZ archive content.
2. Run the uninstall.sh script.

NOTE:

The uninstall.sh script erases all packages that match “opencl-1.2”.

You can use the OS-specific command to remove all the packages, starting with 'opencl-1.2-'. To do so, run the following commands:

For Red Hat Enterprise Linux OS:

# sudo yum remove "opencl-1.2-*"

For SUSE Linux Enterprise OS:

# sudo zypper remove "opencl-1.2-*"

Resolved Issues

• In the Intel Xeon Phi coprocessor device
• The following Built-in functions are now spec-conformant: rootn, pown, half
• Fixed “internal error (Program)(0, 0)” appeared in customer code
• Fixed code generation defect around the slt and sgt instructions
• In the Intel Xeon processor device
• clCreateSubdevices(EXT) API doesn’t fail, if the pointer to num_devices_ret is NULL
• No need to log-in with root privileges in order to use the Kernel Builder tool

Issues and Limitations

Known Issues with OpenCL* on Intel® Xeon® processors

• OpenCL requires a specific interface version of TBB, which is included in the OpenCL install folder. The user of OpenCL is requested to prevent TBB versioning conflict.

  When an OpenCL application is invoked, the OpenCL path should be the first path in LD_LIBRARY_PATH.

  For example:

  On CSH - setenv LD_LIBRARY_PATH ${OCL_INSTALL_DIR}\bin:${LD_LIBRARY_PATH}

             On BASH - export LD_LIBRARY_PATH=${OCL_INSTALL_DIR}\bin:${LD_LIBRARY_PATH}

• An attempt to use clCreateSubdevicesEXT fails if the target device for partitioning is part of a context. No such limitation exists for clCreateSubdevices. Use the clCreateSubdevices function as the EXT support is deprecated and will be eliminated in future versions.

Known Issues with OpenCL on Intel® Xeon Phi™ Coprocessors

• Device transfer from/to non 64B aligned host ptr, results in low throughput
• Intel VTune Amplifier XE “source code view” is not supported. Disassembly view is supported
• Suboptimal integer sdiv, udiv, srem, and urem

Intel® Xeon Phi™ Coprocessor OpenCL Device Limitations

• No support for OpenCL images object type
• No support for sub devices (also known as device fission on the CPU)