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Counting the number of physical CPUS

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GetProcAddress function. Retrieves the address of an exported function or variable from the specified dynamic-link library (DLL). Syntax FARPROC WINAPI GetProcAddress( _In_ HMODULE hModule, _In_ LPCSTR lpProcName ); Parameters hModule [in] lpProcName [in] The function or variable name, or the function's ordinal value. Return value If the function succeeds, the return value is the address of the exported function or variable. Remarks The lpProcName parameter can identify the DLL function by specifying an ordinal value associated with the function in the EXPORTS statement.

If the .def file does not number the functions consecutively from 1 to N (where N is the number of exported functions), an error can occur where GetProcAddress returns an invalid, non-NULL address, even though there is no function with the specified ordinal. typedef void (WINAPI *PGNSI)(LPSYSTEM_INFO); // Call GetNativeSystemInfo if supported or GetSystemInfo otherwise. Windows Phone 8: This API is supported. Windows Phone 8.1: This API is supported. Using the Windows Headers.

Visual C++ and the Windows Header Files Microsoft Visual C++ includes copies of the Windows header files that were current at the time Visual C++ was released. Therefore, if you install updated header files from an SDK, you may end up with multiple versions of the Windows header files on your computer. If you do not ensure that you are using the latest version of the SDK header files, you will receive the following error code when compiling code that uses features that were introduced after Visual C++ was released: error C2065: undeclared identifier.

Macros for Conditional Declarations Certain functions that depend on a particular version of Windows are declared using conditional code. This enables you to use the compiler to detect whether your application uses functions that are not supported on its target version(s) of Windows. To compile an application that uses these functions, you must define the appropriate macros. Setting WINVER or _WIN32_WINNT #define WINVER 0x0502 Related topics. Ac_cv_type_ Autoconf - Existing Tests. Go to the first, previous, next, last section, table of contents. These macros test for particular system features that packages might need or want to use. If you need to test for a kind of feature that none of these macros check for, you can probably do it by calling primitive test macros with appropriate arguments (see section Writing Tests). These tests print messages telling the user which feature they're checking for, and what they find.

They cache their results for future configure runs (see section Caching Results). Some of these macros set output variables. See section Substitutions in Makefiles, for how to get their values. Alternative Programs These macros check for the presence or behavior of particular programs. Particular Program Checks These macros check for particular programs--whether they exist, and in some cases whether they support certain features. Macro: AC_DECL_YYTEXT Define YYTEXT_POINTER if yytext is a `char *' instead of a `char []'.

Macro: AC_PROG_AWK Instead, do. AIX commands you should not leave home without. Shiv DuttaPublished on April 04, 2014 As you know, AIX has a vast array of commands that enable you to do a multitude of tasks. Depending on what you need to accomplish, you use only a certain subset of these commands. These subsets differ from user to user and from need to need. However, there are a few core commands that you commonly use. In this article, I'll discuss some of these core commands. Commands Kernel How do I know if I am running a uniprocessor kernel or a multiprocessor kernel, or a 32-bit kernel or a 64-bit kernel? /unix is a symbolic link to the booted kernel. Note:AIX 5L Version 5.3 does not support a uniprocessor kernel. How can I change from one kernel mode to another? During the installation process, one of the kernels, appropriate for the AIX version and the hardware in operation, is enabled by default.

The /dev/hdiskxx directory is where the boot logical volume /dev/hd5 is located. Note:In AIX V5.2, the 32-bit kernel is installed by default. Hardware Type the following: Modman.unixdev.net - Page: pstat_getprocessor(2) in [HP-UX-11.11] HP-UX - how get hardware (server,card,slot) information | AdminDot. HP-UX - how get hardware (server,card,slot) information | AdminDot.

How to get CPU socket and core information? NUMA Frequently Asked Questions. System Descriptions. This section will describe various platforms. Some of them may exist at this time, while others are fictional and may someday be manufactured. The intent is to show the diversity of potential system topologies. The systems described in this document include: A typical SMP system. The Alpha Wildfire system. The IBM Numa-Q system. A typical SMP system The following diagram shows a typical SMP system design, utilizing Intel x86 processors: The typical SMP system includes multiple CPUs. Compaq / Alpha Wildfire Currently searching for more information. The IBM Numa-Q system The IBM Numa-Q system design is depicted in the following diagram: Each node in the system is simply a 4 processor SMP system. Slicon Graphics Mips64 CPU/Memory ring system The following diagram shows a theoretical system in which each CPU connects two independant memory nodes and each memory nodes connects to two CPUs: As can be seen, the end result of such a system is a ring configuration.

Multiple CPU on a single chip. Hwloc Tutorials. Tutoriel hwloc @ ComPAS 2013. Non-Uniform Memory Access. Non-uniform memory access (NUMA) is a computer memory design used in multiprocessing, where the memory access time depends on the memory location relative to the processor. Under NUMA, a processor can access its own local memory faster than non-local memory (memory local to another processor or memory shared between processors). The benefits of NUMA are limited to particular workloads, notably on servers where the data are often associated strongly with certain tasks or users.[1] NUMA architectures logically follow in scaling from symmetric multiprocessing (SMP) architectures. They were developed commercially during the 1990s by Burroughs (later Unisys), Convex Computer (later Hewlett-Packard), Honeywell Information Systems Italy (HISI) (later Groupe Bull), Silicon Graphics (later Silicon Graphics International), Sequent Computer Systems (later IBM), Data General (later EMC), and Digital (later Compaq, now HP).

Basic concept[edit] One possible architecture of a NUMA system. Hwloc: Portable Hardware Locality. Context The democratization of multicore processors and NUMA architectures (AMD HyperTransport, Intel QPI, ...) leads to the spreading of complex hardware topologies into the whole server world. While large shared-memory machines were formerly very rare, nodaways every single cluster node may contain 12 cores, hierarchical caches, or multiple threads per core, making its topology far from flat.

Such complex and hierarchical topologies have strong impact of the application performance. The developer must take hardware affinities into account when trying to exploit the actual hardware performance. Hwloc provides a portable abstraction (across OS, versions, architectures, ...) of the hierarchical topology of modern architectures, including NUMA memory nodes, sockets, shared caches, cores and simultaneous multithreading.

Hwloc also offers affinity information about I/O devices such as network interfaces, InfiniBand HCAs or GPUs. Credits. BlueBrain/hwloc. Hwloc-v1.1.1-letter.pdf. Strange cpuinfo, how many cores does these physical cpu has. Portable Hardware Locality (hwloc) The Portable Hardware Locality (hwloc) software package provides a portable abstraction (across OS, versions, architectures, ...) of the hierarchical topology of modern architectures, including NUMA memory nodes, sockets, shared caches, cores and simultaneous multithreading. It also gathers various system attributes such as cache and memory information as well as the locality of I/O devices such as network interfaces, InfiniBand HCAs or GPUs.

It primarily aims at helping applications with gathering information about modern computing hardware so as to exploit it accordingly and efficiently. Portability and support hwloc supports the following operating systems: Linux (including old kernels not having sysfs topology information, with knowledge of cpusets, offline CPUs, ScaleMP vSMP, NumaScale NumaConnect, and Kerrighed support)SolarisAIXDarwin / OS XFreeBSD and its variants (such as kFreeBSD/GNU)NetBSDOSF/1 (a.k.a., Tru64)HP-UXMicrosoft WindowsIBM BlueGene/Q Compute Node Kernel (CNK) Portable Hardware Locality (hwloc) Portable Hardware Locality (hwloc) Documentation: v1.7.1. Hwloc provides command line tools and a C API to obtain the hierarchical map of key computing elements, such as: NUMA memory nodes, shared caches, processor sockets, processor cores, processing units (logical processors or "threads") and even I/O devices. hwloc also gathers various attributes such as cache and memory information, and is portable across a variety of different operating systems and platforms.

Additionally it may assemble the topologies of multiple machines into a single one so as to let applications consult the topology of an entire fabric or cluster at once. hwloc primarily aims at helping high-performance computing (HPC) applications, but is also applicable to any project seeking to exploit code and/or data locality on modern computing platforms. Note that the hwloc project represents the merger of the libtopology project from inria and the Portable Linux Processor Affinity (PLPA) sub-project from Open MPI. Both of these prior projects are now deprecated.

Shell$ . . i++) { c02267025.pdf. SYSTEM_INFO structure. Contains information about the current computer system. This includes the architecture and type of the processor, the number of processors in the system, the page size, and other such information. Syntax typedef struct _SYSTEM_INFO { union { DWORD dwOemId; struct { WORD wProcessorArchitecture; WORD wReserved; }; }; DWORD dwPageSize; LPVOID lpMinimumApplicationAddress; LPVOID lpMaximumApplicationAddress; DWORD_PTR dwActiveProcessorMask; DWORD dwNumberOfProcessors; DWORD dwProcessorType; DWORD dwAllocationGranularity; WORD wProcessorLevel; WORD wProcessorRevision; } SYSTEM_INFO; Members dwOemId An obsolete member that is retained for compatibility.

Applications should use the wProcessorArchitecture branch of the union. wProcessorArchitecture The processor architecture of the installed operating system. wReserved This member is reserved for future use. dwPageSize lpMinimumApplicationAddress A pointer to the lowest memory address accessible to applications and dynamic-link libraries (DLLs). Examples. UX Software Transition Kit. Pstat - pstat() functional interface changes (NcWn726) Problem description The pstat system call has been modified so that pstat_getdynamic() accounts for the new instant activation of additional processors without needing to reboot the system.

In previous versions of pstat_getdynamic(), the returned fields psd_proc_cnt (number of active processors) and psd_max_proc_cnt (maximum active processors) had the same value. This was because all of the processors in the system were active. These fields may have been used interchangeably even though they had different meanings. With Hewlett-Packard's Instant Capacity Once Demand (iCOD), available with certain computer models, not all of the processors have to be active within the computer. The pstat system call is changed such that a call to pstat_getdynamic() will return the field psd_proc_cnt containing the number of allocated (active) processors. Identifiers See also Problem summary. Get_nprocs_conf(3) - Linux manual page. GET_NPROCS(3) Linux Programmer's Manual GET_NPROCS(3) NAME top get_nprocs, get_nprocs_conf - get number of processors SYNOPSIS top #include <sys/sysinfo.h> int get_nprocs(void); int get_nprocs_conf(void); DESCRIPTION top The function get_nprocs_conf() returns the number of processors configured by the operating system.

RETURN VALUE top As given in DESCRIPTION. CONFORMING TO top These functions are GNU extensions. NOTES top The current implementation of these functions is rather expensive, since they open and parse files in the /sys filesystem each time they are called. EXAMPLE top The following example shows how get_nprocs() and get_nprocs_conf() can be used. COLOPHON top This page is part of release 3.65 of the Linux man-pages project. Copyright and license for this manual page. Linux: Find Number of CPU Cores Command. How do I find out the number of CPU cores available under HP x86_64 Linux serer running on RHEL / Debian Linux 6.x? You can use the lscpu or nproc command to display the number of processing units available to the current process, which may be less than the number of online processors (please note that not all server supports hotplug a CPU on a running Linux system).

The proc file system is a pseudo-file system which is used as an interface to kernel data structures. It is commonly mounted at /proc. The /proc/cpuinfo file is nothing but a collection of CPU and system architecture dependent items, for each supported architecture a different list. Two common entries are processor which gives CPU number and bogomips; a system constant that is calculated during kernel initialization. Nproc Example The nproc command shows the number of processing units available: # nproc Sample outputs: lscpu Command /proc/cpuinfo Check out related media Here is a quick demo of lscpu and /proc/cpuinfo commands: C++ - Programmatically find the number of cores on a machine. Ia64. Processor topology information is important for a number of processor-resource management practices, ranging from task/thread scheduling, licensing policy enforcement, affinity control/migration, etc.

Topology information of the cache hierarchy can be important to optimizing software performance. This white paper covers topology enumeration algorithm for single-socket to multiple-socket platforms using Intel 64 and IA-32 processors. The topology enumeration algorithms (both processor and cache) using initial APIC ID has been extended to use x2APIC ID, the latter mechanism is required for future platforms supporting more than 256 logical processors in a coherent domain. Download "Intel® 64 Architecture Processor Topology Enumeration" [PDF 153KB] Download Code Package: topo-09272010.tar Introduction Hardware multithreading in microprocessors has proliferated in recent years. Intel 64 processors fulfill system topology enumeration requirements: Unique APIC ID in a Multi-Processor System.

Aix machine - licensing. AIX > Administrator > LPAR Use the lparstat command to obtain an accurate understanding of LPAR processing resources For AIX-based Power Systems servers, many software vendors base their licensing on processor core counts. With the many configuration options available under PowerVM, it’s become a challenge to track the number of processor cores that a particular LPAR can access. This article will show you how the AIX lparstat command can determine the number of cores each LPAR can access. The number of LPARs running a particular software package and the shared processor pool configuration also come into play when determining how many total cores to license. The information in this article can help track software licensing and assist with software vendor audit requests. Running lparstat For AIX 5.3 and higher, run the lparstat command with the –i flag to display the LPAR configuration details: # lparstat -i A variety of parameters will be returned when this command is run.

AIX OS. AIX machine. AIX machine. Windows, Mac or Linux.