Merge pull request #17556 from ClickHouse/memory-amount-worse

getMemoryAmount: make code worse
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alexey-milovidov 2020-11-30 12:53:50 +03:00 committed by GitHub
commit 81e4885664
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@ -1,100 +1,28 @@
#include <stdexcept>
#include "common/getMemoryAmount.h"
// http://nadeausoftware.com/articles/2012/09/c_c_tip_how_get_physical_memory_size_system
/*
* Author: David Robert Nadeau
* Site: http://NadeauSoftware.com/
* License: Creative Commons Attribution 3.0 Unported License
* http://creativecommons.org/licenses/by/3.0/deed.en_US
*/
#if defined(WIN32) || defined(_WIN32)
#include <Windows.h>
#else
#include <unistd.h>
#include <sys/types.h>
#include <sys/param.h>
#if defined(BSD)
#include <sys/sysctl.h>
#endif
#endif
/**
* Returns the size of physical memory (RAM) in bytes.
* Returns 0 on unsupported platform
*/
/** Returns the size of physical memory (RAM) in bytes.
* Returns 0 on unsupported platform
*/
uint64_t getMemoryAmountOrZero()
{
#if defined(_WIN32) && (defined(__CYGWIN__) || defined(__CYGWIN32__))
/* Cygwin under Windows. ------------------------------------ */
/* New 64-bit MEMORYSTATUSEX isn't available. Use old 32.bit */
MEMORYSTATUS status;
status.dwLength = sizeof(status);
GlobalMemoryStatus(&status);
return status.dwTotalPhys;
int64_t num_pages = sysconf(_SC_PHYS_PAGES);
if (num_pages <= 0)
return 0;
#elif defined(WIN32) || defined(_WIN32)
/* Windows. ------------------------------------------------- */
/* Use new 64-bit MEMORYSTATUSEX, not old 32-bit MEMORYSTATUS */
MEMORYSTATUSEX status;
status.dwLength = sizeof(status);
GlobalMemoryStatusEx(&status);
return status.ullTotalPhys;
int64_t page_size = sysconf(_SC_PAGESIZE);
if (page_size <= 0)
return 0;
#else
/* UNIX variants. ------------------------------------------- */
/* Prefer sysctl() over sysconf() except sysctl() HW_REALMEM and HW_PHYSMEM */
#if defined(CTL_HW) && (defined(HW_MEMSIZE) || defined(HW_PHYSMEM64))
int mib[2];
mib[0] = CTL_HW;
#if defined(HW_MEMSIZE)
mib[1] = HW_MEMSIZE; /* OSX. --------------------- */
#elif defined(HW_PHYSMEM64)
mib[1] = HW_PHYSMEM64; /* NetBSD, OpenBSD. --------- */
#endif
uint64_t size = 0; /* 64-bit */
size_t len = sizeof(size);
if (sysctl(mib, 2, &size, &len, nullptr, 0) == 0)
return size;
return 0; /* Failed? */
#elif defined(_SC_AIX_REALMEM)
/* AIX. ----------------------------------------------------- */
return sysconf(_SC_AIX_REALMEM) * 1024;
#elif defined(_SC_PHYS_PAGES) && defined(_SC_PAGESIZE)
/* FreeBSD, Linux, OpenBSD, and Solaris. -------------------- */
return uint64_t(sysconf(_SC_PHYS_PAGES))
*uint64_t(sysconf(_SC_PAGESIZE));
#elif defined(_SC_PHYS_PAGES) && defined(_SC_PAGE_SIZE)
/* Legacy. -------------------------------------------------- */
return uint64_t(sysconf(_SC_PHYS_PAGES))
* uint64_t(sysconf(_SC_PAGE_SIZE));
#elif defined(CTL_HW) && (defined(HW_PHYSMEM) || defined(HW_REALMEM))
/* DragonFly BSD, FreeBSD, NetBSD, OpenBSD, and OSX. -------- */
int mib[2];
mib[0] = CTL_HW;
#if defined(HW_REALMEM)
mib[1] = HW_REALMEM; /* FreeBSD. ----------------- */
#elif defined(HW_PYSMEM)
mib[1] = HW_PHYSMEM; /* Others. ------------------ */
#endif
unsigned int size = 0; /* 32-bit */
size_t len = sizeof(size);
if (sysctl(mib, 2, &size, &len, nullptr, 0) == 0)
return size;
return 0; /* Failed? */
#endif /* sysctl and sysconf variants */
#endif
return num_pages * page_size;
}