llsys.cpp

/** 
 * @file llsys.cpp
 * @brief Implementation of the basic system query functions.
 *
 * $LicenseInfo:firstyear=2002&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#if LL_WINDOWS
#pragma warning (disable : 4355) // 'this' used in initializer list: yes, intentionally
#endif

#include "linden_common.h"

#include "llsys.h"

#include <iostream>
#ifdef LL_USESYSTEMLIBS
# include <zlib.h>
#else
# include "zlib/zlib.h"
#endif

#include "llprocessor.h"
#include "llerrorcontrol.h"
#include "llevents.h"
#include "llformat.h"
#include "lltimer.h"
#include "llsdserialize.h"
#include "llsdutil.h"
#include <boost/bind.hpp>
#include <boost/circular_buffer.hpp>
#include <boost/regex.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/range.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/type_traits/is_integral.hpp>
#include <boost/type_traits/is_float.hpp>

using namespace llsd;

#if LL_WINDOWS
#	include "llwin32headerslean.h"
#   include <psapi.h>               // GetPerformanceInfo() et al.
#	include <VersionHelpers.h>
#elif LL_DARWIN
#   include "llsys_objc.h"
#	include <errno.h>
#	include <sys/sysctl.h>
#	include <sys/utsname.h>
#	include <stdint.h>
#	include <CoreServices/CoreServices.h>
#   include <stdexcept>
#	include <mach/host_info.h>
#	include <mach/mach_host.h>
#	include <mach/task.h>
#	include <mach/task_info.h>
#elif LL_LINUX
#	include <errno.h>
#	include <sys/utsname.h>
#	include <unistd.h>
#	include <sys/sysinfo.h>
#   include <stdexcept>
const char MEMINFO_FILE[] = "/proc/meminfo";
#   include <gnu/libc-version.h>
#elif LL_SOLARIS
#	include <stdio.h>
#	include <unistd.h>
#	include <sys/utsname.h>
#	define _STRUCTURED_PROC 1
#	include <sys/procfs.h>
#	include <sys/types.h>
#	include <sys/stat.h>
#	include <fcntl.h>
#	include <errno.h>
extern int errno;
#endif

LLCPUInfo gSysCPU;

// Don't log memory info any more often than this. It also serves as our
// framerate sample size.
static const F32 MEM_INFO_THROTTLE = 20;
// Sliding window of samples. We intentionally limit the length of time we
// remember "the slowest" framerate because framerate is very slow at login.
// If we only triggered FrameWatcher logging when the session framerate
// dropped below the login framerate, we'd have very little additional data.
static const F32 MEM_INFO_WINDOW = 10*60;

// Wrap boost::regex_match() with a function that doesn't throw.
template <typename S, typename M, typename R>
static bool regex_match_no_exc(const S& string, M& match, const R& regex)
{
    try
    {
        return boost::regex_match(string, match, regex);
    }
    catch (const std::runtime_error& e)
    {
        LL_WARNS("LLMemoryInfo") << "error matching with '" << regex.str() << "': "
                                 << e.what() << ":\n'" << string << "'" << LL_ENDL;
        return false;
    }
}

// Wrap boost::regex_search() with a function that doesn't throw.
template <typename S, typename M, typename R>
static bool regex_search_no_exc(const S& string, M& match, const R& regex)
{
    try
    {
        return boost::regex_search(string, match, regex);
    }
    catch (const std::runtime_error& e)
    {
        LL_WARNS("LLMemoryInfo") << "error searching with '" << regex.str() << "': "
                                 << e.what() << ":\n'" << string << "'" << LL_ENDL;
        return false;
    }
}


LLOSInfo::LLOSInfo() :
	mMajorVer(0), mMinorVer(0), mBuild(0), mOSVersionString("")	 
{

#if LL_WINDOWS

	if (IsWindows10OrGreater())
	{
		mMajorVer = 10;
		mMinorVer = 0;
		if (IsWindowsServer())
		{
			mOSStringSimple = "Windows Server ";
		}
		else
		{
			mOSStringSimple = "Microsoft Windows 10 ";
		}
	}
	else if (IsWindows8Point1OrGreater())
	{
		mMajorVer = 6;
		mMinorVer = 3;
		if (IsWindowsServer())
		{
			mOSStringSimple = "Windows Server 2012 R2 ";
		}
		else
		{
			mOSStringSimple = "Microsoft Windows 8.1 ";
		}
	}
	else if (IsWindows8OrGreater())
	{
		mMajorVer = 6;
		mMinorVer = 2;
		if (IsWindowsServer())
		{
			mOSStringSimple = "Windows Server 2012 ";
		}
		else
		{
			mOSStringSimple = "Microsoft Windows 8 ";
		}
	}
	else if (IsWindows7SP1OrGreater())
	{
		mMajorVer = 6;
		mMinorVer = 1;
		if (IsWindowsServer())
		{
			mOSStringSimple = "Windows Server 2008 R2 SP1 ";
		}
		else
		{
			mOSStringSimple = "Microsoft Windows 7 SP1 ";
		}
	}
	else if (IsWindows7OrGreater())
	{
		mMajorVer = 6;
		mMinorVer = 1;
		if (IsWindowsServer())
		{
			mOSStringSimple = "Windows Server 2008 R2 ";
		}
		else
		{
			mOSStringSimple = "Microsoft Windows 7 ";
		}
	}
	else if (IsWindowsVistaSP2OrGreater())
	{
		mMajorVer = 6;
		mMinorVer = 0;
		if (IsWindowsServer())
		{
			mOSStringSimple = "Windows Server 2008 SP2 ";
		}
		else
		{
			mOSStringSimple = "Microsoft Windows Vista SP2 ";
		}
	}
	else
	{
		mOSStringSimple = "Unsupported Windows version ";
	}

	///get native system info if available..
	typedef void (WINAPI *PGNSI)(LPSYSTEM_INFO); ///function pointer for loading GetNativeSystemInfo
	SYSTEM_INFO si; //System Info object file contains architecture info
	PGNSI pGNSI; //pointer object
	ZeroMemory(&si, sizeof(SYSTEM_INFO)); //zero out the memory in information
	pGNSI = (PGNSI)GetProcAddress(GetModuleHandle(TEXT("kernel32.dll")), "GetNativeSystemInfo"); //load kernel32 get function
	if (NULL != pGNSI) //check if it has failed
		pGNSI(&si); //success
	else
		GetSystemInfo(&si); //if it fails get regular system info 
	//(Warning: If GetSystemInfo it may result in incorrect information in a WOW64 machine, if the kernel fails to load)

	//msdn microsoft finds 32 bit and 64 bit flavors this way..
	//http://msdn.microsoft.com/en-us/library/ms724429(VS.85).aspx (example code that contains quite a few more flavors
	//of windows than this code does (in case it is needed for the future)
	if (si.wProcessorArchitecture == PROCESSOR_ARCHITECTURE_AMD64) //check for 64 bit
	{
		mOSStringSimple += "64-bit ";
	}
	else if (si.wProcessorArchitecture == PROCESSOR_ARCHITECTURE_INTEL)
	{
		mOSStringSimple += "32-bit ";
	}

	// Try calling GetVersionEx using the OSVERSIONINFOEX structure.
	OSVERSIONINFOEX osvi;
	ZeroMemory(&osvi, sizeof(OSVERSIONINFOEX));
	osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
	if (GetVersionEx((OSVERSIONINFO *)&osvi))
	{
		mBuild = osvi.dwBuildNumber & 0xffff;
	}
	else
	{
		// If OSVERSIONINFOEX doesn't work, try OSVERSIONINFO.
		osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
		if (GetVersionEx((OSVERSIONINFO *)&osvi))
		{
			mBuild = osvi.dwBuildNumber & 0xffff;
		}
	}

	S32 ubr = 0; // Windows 10 Update Build Revision, can be retrieved from a registry
	if (mMajorVer == 10)
	{
		DWORD cbData(sizeof(DWORD));
		DWORD data(0);
		HKEY key;
		BOOL ret_code = RegOpenKeyExW(HKEY_LOCAL_MACHINE, TEXT("SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion"), 0, KEY_READ, &key);
		if (ERROR_SUCCESS == ret_code)
		{
			ret_code = RegQueryValueExW(key, L"UBR", 0, NULL, reinterpret_cast<LPBYTE>(&data), &cbData);
			if (ERROR_SUCCESS == ret_code)
			{
				ubr = data;
			}
		}
	}

	mOSString = mOSStringSimple;
	if (mBuild > 0)
	{
		mOSString += llformat("(Build %d", mBuild);
		if (ubr > 0)
		{
			mOSString += llformat(".%d", ubr);
		}
		mOSString += ")";
	}

	LLStringUtil::trim(mOSStringSimple);
	LLStringUtil::trim(mOSString);

#elif LL_DARWIN
	
	// Initialize mOSStringSimple to something like:
	// "macOS 10.6.7"
	{
		S32 major_version, minor_version, bugfix_version = 0;

		if (LLSysDarwin::getOperatingSystemInfo(major_version, minor_version, bugfix_version))
		{
			mMajorVer = major_version;
			mMinorVer = minor_version;
			mBuild = bugfix_version;

            const char * DARWIN_PRODUCT_NAME = "macOS";
            
			std::stringstream os_version_string;
			os_version_string << DARWIN_PRODUCT_NAME << " " << mMajorVer << "." << mMinorVer << "." << mBuild;
			
			// Put it in the OS string we are compiling
			mOSStringSimple.append(os_version_string.str());
		}
		else
		{
			mOSStringSimple.append("Unable to collect OS info");
		}
	}
	
	// Initialize mOSString to something like:
	// "macOS 10.6.7 Darwin Kernel Version 10.7.0: Sat Jan 29 15:17:16 PST 2011; root:xnu-1504.9.37~1/RELEASE_I386 i386"
	struct utsname un;
	if(uname(&un) != -1)
	{		
		mOSString = mOSStringSimple;
		mOSString.append(" ");
		mOSString.append(un.sysname);
		mOSString.append(" ");
		mOSString.append(un.release);
		mOSString.append(" ");
		mOSString.append(un.version);
		mOSString.append(" ");
		mOSString.append(un.machine);
	}
	else
	{
		mOSString = mOSStringSimple;
	}
	
#elif LL_LINUX
	
	struct utsname un;
	if(uname(&un) != -1)
	{
		mOSStringSimple.append(un.sysname);
		mOSStringSimple.append(" ");
		mOSStringSimple.append(un.release);

		mOSString = mOSStringSimple;
		mOSString.append(" ");
		mOSString.append(un.version);
		mOSString.append(" ");
		mOSString.append(un.machine);

		// Simplify 'Simple'
		std::string ostype = mOSStringSimple.substr(0, mOSStringSimple.find_first_of(" ", 0));
		if (ostype == "Linux")
		{
			// Only care about major and minor Linux versions, truncate at second '.'
			std::string::size_type idx1 = mOSStringSimple.find_first_of(".", 0);
			std::string::size_type idx2 = (idx1 != std::string::npos) ? mOSStringSimple.find_first_of(".", idx1+1) : std::string::npos;
			std::string simple = mOSStringSimple.substr(0, idx2);
			if (simple.length() > 0)
				mOSStringSimple = simple;
		}
	}
	else
	{
		mOSStringSimple.append("Unable to collect OS info");
		mOSString = mOSStringSimple;
	}

	const char OS_VERSION_MATCH_EXPRESSION[] = "([0-9]+)\\.([0-9]+)(\\.([0-9]+))?";
	boost::regex os_version_parse(OS_VERSION_MATCH_EXPRESSION);
	boost::smatch matched;

	std::string glibc_version(gnu_get_libc_version());
	if ( regex_match_no_exc(glibc_version, matched, os_version_parse) )
	{
		LL_INFOS("AppInit") << "Using glibc version '" << glibc_version << "' as OS version" << LL_ENDL;
	
		std::string version_value;

		if ( matched[1].matched ) // Major version
		{
			version_value.assign(matched[1].first, matched[1].second);
			if (sscanf(version_value.c_str(), "%d", &mMajorVer) != 1)
			{
			  LL_WARNS("AppInit") << "failed to parse major version '" << version_value << "' as a number" << LL_ENDL;
			}
		}
		else
		{
			LL_ERRS("AppInit")
				<< "OS version regex '" << OS_VERSION_MATCH_EXPRESSION 
				<< "' returned true, but major version [1] did not match"
				<< LL_ENDL;
		}

		if ( matched[2].matched ) // Minor version
		{
			version_value.assign(matched[2].first, matched[2].second);
			if (sscanf(version_value.c_str(), "%d", &mMinorVer) != 1)
			{
			  LL_ERRS("AppInit") << "failed to parse minor version '" << version_value << "' as a number" << LL_ENDL;
			}
		}
		else
		{
			LL_ERRS("AppInit")
				<< "OS version regex '" << OS_VERSION_MATCH_EXPRESSION 
				<< "' returned true, but minor version [1] did not match"
				<< LL_ENDL;
		}

		if ( matched[4].matched ) // Build version (optional) - note that [3] includes the '.'
		{
			version_value.assign(matched[4].first, matched[4].second);
			if (sscanf(version_value.c_str(), "%d", &mBuild) != 1)
			{
			  LL_ERRS("AppInit") << "failed to parse build version '" << version_value << "' as a number" << LL_ENDL;
			}
		}
		else
		{
			LL_INFOS("AppInit")
				<< "OS build version not provided; using zero"
				<< LL_ENDL;
		}
	}
	else
	{
		LL_WARNS("AppInit") << "glibc version '" << glibc_version << "' cannot be parsed to three numbers; using all zeros" << LL_ENDL;
	}

#else
	
	struct utsname un;
	if(uname(&un) != -1)
	{
		mOSStringSimple.append(un.sysname);
		mOSStringSimple.append(" ");
		mOSStringSimple.append(un.release);

		mOSString = mOSStringSimple;
		mOSString.append(" ");
		mOSString.append(un.version);
		mOSString.append(" ");
		mOSString.append(un.machine);

		// Simplify 'Simple'
		std::string ostype = mOSStringSimple.substr(0, mOSStringSimple.find_first_of(" ", 0));
		if (ostype == "Linux")
		{
			// Only care about major and minor Linux versions, truncate at second '.'
			std::string::size_type idx1 = mOSStringSimple.find_first_of(".", 0);
			std::string::size_type idx2 = (idx1 != std::string::npos) ? mOSStringSimple.find_first_of(".", idx1+1) : std::string::npos;
			std::string simple = mOSStringSimple.substr(0, idx2);
			if (simple.length() > 0)
				mOSStringSimple = simple;
		}
	}
	else
	{
		mOSStringSimple.append("Unable to collect OS info");
		mOSString = mOSStringSimple;
	}

#endif

	std::stringstream dotted_version_string;
	dotted_version_string << mMajorVer << "." << mMinorVer << "." << mBuild;
	mOSVersionString.append(dotted_version_string.str());

}

#ifndef LL_WINDOWS
// static
S32 LLOSInfo::getMaxOpenFiles()
{
	const S32 OPEN_MAX_GUESS = 256;

#ifdef	OPEN_MAX
	static S32 open_max = OPEN_MAX;
#else
	static S32 open_max = 0;
#endif

	if (0 == open_max)
	{
		// First time through.
		errno = 0;
		if ( (open_max = sysconf(_SC_OPEN_MAX)) < 0)
		{
			if (0 == errno)
			{
				// Indeterminate.
				open_max = OPEN_MAX_GUESS;
			}
			else
			{
				LL_ERRS() << "LLOSInfo::getMaxOpenFiles: sysconf error for _SC_OPEN_MAX" << LL_ENDL;
			}
		}
	}
	return open_max;
}
#endif

void LLOSInfo::stream(std::ostream& s) const
{
	s << mOSString;
}

const std::string& LLOSInfo::getOSString() const
{
	return mOSString;
}

const std::string& LLOSInfo::getOSStringSimple() const
{
	return mOSStringSimple;
}

const std::string& LLOSInfo::getOSVersionString() const
{
	return mOSVersionString;
}

//static
U32 LLOSInfo::getProcessVirtualSizeKB()
{
	U32 virtual_size = 0;
#if LL_WINDOWS
#endif
#if LL_LINUX
#   define STATUS_SIZE 2048	
	LLFILE* status_filep = LLFile::fopen("/proc/self/status", "rb");
	if (status_filep)
	{
		S32 numRead = 0;		
		char buff[STATUS_SIZE];		/* Flawfinder: ignore */

		size_t nbytes = fread(buff, 1, STATUS_SIZE-1, status_filep);
		buff[nbytes] = '\0';

		// All these guys return numbers in KB
		char *memp = strstr(buff, "VmSize:");
		if (memp)
		{
			numRead += sscanf(memp, "%*s %u", &virtual_size);
		}
		fclose(status_filep);
	}
#elif LL_SOLARIS
	char proc_ps[LL_MAX_PATH];
	sprintf(proc_ps, "/proc/%d/psinfo", (int)getpid());
	int proc_fd = -1;
	if((proc_fd = open(proc_ps, O_RDONLY)) == -1){
		LL_WARNS() << "unable to open " << proc_ps << LL_ENDL;
		return 0;
	}
	psinfo_t proc_psinfo;
	if(read(proc_fd, &proc_psinfo, sizeof(psinfo_t)) != sizeof(psinfo_t)){
		LL_WARNS() << "Unable to read " << proc_ps << LL_ENDL;
		close(proc_fd);
		return 0;
	}

	close(proc_fd);

	virtual_size = proc_psinfo.pr_size;
#endif
	return virtual_size;
}

//static
U32 LLOSInfo::getProcessResidentSizeKB()
{
	U32 resident_size = 0;
#if LL_WINDOWS
#endif
#if LL_LINUX
	LLFILE* status_filep = LLFile::fopen("/proc/self/status", "rb");
	if (status_filep != NULL)
	{
		S32 numRead = 0;
		char buff[STATUS_SIZE];		/* Flawfinder: ignore */

		size_t nbytes = fread(buff, 1, STATUS_SIZE-1, status_filep);
		buff[nbytes] = '\0';

		// All these guys return numbers in KB
		char *memp = strstr(buff, "VmRSS:");
		if (memp)
		{
			numRead += sscanf(memp, "%*s %u", &resident_size);
		}
		fclose(status_filep);
	}
#elif LL_SOLARIS
	char proc_ps[LL_MAX_PATH];
	sprintf(proc_ps, "/proc/%d/psinfo", (int)getpid());
	int proc_fd = -1;
	if((proc_fd = open(proc_ps, O_RDONLY)) == -1){
		LL_WARNS() << "unable to open " << proc_ps << LL_ENDL;
		return 0;
	}
	psinfo_t proc_psinfo;
	if(read(proc_fd, &proc_psinfo, sizeof(psinfo_t)) != sizeof(psinfo_t)){
		LL_WARNS() << "Unable to read " << proc_ps << LL_ENDL;
		close(proc_fd);
		return 0;
	}

	close(proc_fd);

	resident_size = proc_psinfo.pr_rssize;
#endif
	return resident_size;
}

LLCPUInfo::LLCPUInfo()
{
	std::ostringstream out;
	LLProcessorInfo proc;
	// proc.WriteInfoTextFile("procInfo.txt");
	mHasSSE = proc.hasSSE();
	mHasSSE2 = proc.hasSSE2();
	mHasAltivec = proc.hasAltivec();
	mCPUMHz = (F64)proc.getCPUFrequency();
	mFamily = proc.getCPUFamilyName();
	mCPUString = "Unknown";

	out << proc.getCPUBrandName();
	if (200 < mCPUMHz && mCPUMHz < 10000)           // *NOTE: cpu speed is often way wrong, do a sanity check
	{
		out << " (" << mCPUMHz << " MHz)";
	}
	mCPUString = out.str();
	LLStringUtil::trim(mCPUString);
}

bool LLCPUInfo::hasAltivec() const
{
	return mHasAltivec;
}

bool LLCPUInfo::hasSSE() const
{
	return mHasSSE;
}

bool LLCPUInfo::hasSSE2() const
{
	return mHasSSE2;
}

F64 LLCPUInfo::getMHz() const
{
	return mCPUMHz;
}

std::string LLCPUInfo::getCPUString() const
{
	return mCPUString;
}

void LLCPUInfo::stream(std::ostream& s) const
{
	// gather machine information.
	s << LLProcessorInfo().getCPUFeatureDescription();

	// These are interesting as they reflect our internal view of the
	// CPU's attributes regardless of platform
	s << "->mHasSSE:     " << (U32)mHasSSE << std::endl;
	s << "->mHasSSE2:    " << (U32)mHasSSE2 << std::endl;
	s << "->mHasAltivec: " << (U32)mHasAltivec << std::endl;
	s << "->mCPUMHz:     " << mCPUMHz << std::endl;
	s << "->mCPUString:  " << mCPUString << std::endl;
}

// Helper class for LLMemoryInfo: accumulate stats in the form we store for
// LLMemoryInfo::getStatsMap().
class Stats
{
public:
	Stats():
		mStats(LLSD::emptyMap())
	{}

	// Store every integer type as LLSD::Integer.
	template <class T>
	void add(const LLSD::String& name, const T& value,
			 typename boost::enable_if<boost::is_integral<T> >::type* = 0)
	{
		mStats[name] = LLSD::Integer(value);
	}

	// Store every floating-point type as LLSD::Real.
	template <class T>
	void add(const LLSD::String& name, const T& value,
			 typename boost::enable_if<boost::is_float<T> >::type* = 0)
	{
		mStats[name] = LLSD::Real(value);
	}

	// Hope that LLSD::Date values are sufficiently unambiguous.
	void add(const LLSD::String& name, const LLSD::Date& value)
	{
		mStats[name] = value;
	}

	LLSD get() const { return mStats; }

private:
	LLSD mStats;
};

LLMemoryInfo::LLMemoryInfo()
{
	refresh();
}

#if LL_WINDOWS
static U32Kilobytes LLMemoryAdjustKBResult(U32Kilobytes inKB)
{
	// Moved this here from llfloaterabout.cpp

	//! \bug
	// For some reason, the reported amount of memory is always wrong.
	// The original adjustment assumes it's always off by one meg, however
	// errors of as much as 2520 KB have been observed in the value
	// returned from the GetMemoryStatusEx function.  Here we keep the
	// original adjustment from llfoaterabout.cpp until this can be
	// fixed somehow.
	inKB += U32Megabytes(1);

	return inKB;
}
#endif

U32Kilobytes LLMemoryInfo::getPhysicalMemoryKB() const
{
#if LL_WINDOWS
	return LLMemoryAdjustKBResult(U32Kilobytes(mStatsMap["Total Physical KB"].asInteger()));

#elif LL_DARWIN
	// This might work on Linux as well.  Someone check...
	uint64_t phys = 0;
	int mib[2] = { CTL_HW, HW_MEMSIZE };

	size_t len = sizeof(phys);	
	sysctl(mib, 2, &phys, &len, NULL, 0);
	
	return U64Bytes(phys);

#elif LL_LINUX
	U64 phys = 0;
	phys = (U64)(getpagesize()) * (U64)(get_phys_pages());
	return U64Bytes(phys);

#elif LL_SOLARIS
	U64 phys = 0;
	phys = (U64)(getpagesize()) * (U64)(sysconf(_SC_PHYS_PAGES));
	return U64Bytes(phys);

#else
	return 0;

#endif
}

//static
void LLMemoryInfo::getAvailableMemoryKB(U32Kilobytes& avail_physical_mem_kb, U32Kilobytes& avail_virtual_mem_kb)
{
#if LL_WINDOWS
	// Sigh, this shouldn't be a static method, then we wouldn't have to
	// reload this data separately from refresh()
	LLSD statsMap(loadStatsMap());

	avail_physical_mem_kb = (U32Kilobytes)statsMap["Avail Physical KB"].asInteger();
	avail_virtual_mem_kb  = (U32Kilobytes)statsMap["Avail Virtual KB"].asInteger();

#elif LL_DARWIN
	// mStatsMap is derived from vm_stat, look for (e.g.) "kb free":
	// $ vm_stat
	// Mach Virtual Memory Statistics: (page size of 4096 bytes)
	// Pages free:                   462078.
	// Pages active:                 142010.
	// Pages inactive:               220007.
	// Pages wired down:             159552.
	// "Translation faults":      220825184.
	// Pages copy-on-write:         2104153.
	// Pages zero filled:         167034876.
	// Pages reactivated:             65153.
	// Pageins:                     2097212.
	// Pageouts:                      41759.
	// Object cache: 841598 hits of 7629869 lookups (11% hit rate)
	avail_physical_mem_kb = (U32Kilobytes)-1 ;
	avail_virtual_mem_kb = (U32Kilobytes)-1 ;

#elif LL_LINUX
	// mStatsMap is derived from MEMINFO_FILE:
	// $ cat /proc/meminfo
	// MemTotal:        4108424 kB
	// MemFree:         1244064 kB
	// Buffers:           85164 kB
	// Cached:          1990264 kB
	// SwapCached:            0 kB
	// Active:          1176648 kB
	// Inactive:        1427532 kB
	// Active(anon):     529152 kB
	// Inactive(anon):    15924 kB
	// Active(file):     647496 kB
	// Inactive(file):  1411608 kB
	// Unevictable:          16 kB
	// Mlocked:              16 kB
	// HighTotal:       3266316 kB
	// HighFree:         721308 kB
	// LowTotal:         842108 kB
	// LowFree:          522756 kB
	// SwapTotal:       6384632 kB
	// SwapFree:        6384632 kB
	// Dirty:                28 kB
	// Writeback:             0 kB
	// AnonPages:        528820 kB
	// Mapped:            89472 kB
	// Shmem:             16324 kB
	// Slab:             159624 kB
	// SReclaimable:     145168 kB
	// SUnreclaim:        14456 kB
	// KernelStack:        2560 kB
	// PageTables:         5560 kB
	// NFS_Unstable:          0 kB
	// Bounce:                0 kB
	// WritebackTmp:          0 kB
	// CommitLimit:     8438844 kB
	// Committed_AS:    1271596 kB
	// VmallocTotal:     122880 kB
	// VmallocUsed:       65252 kB
	// VmallocChunk:      52356 kB
	// HardwareCorrupted:     0 kB
	// HugePages_Total:       0
	// HugePages_Free:        0
	// HugePages_Rsvd:        0
	// HugePages_Surp:        0
	// Hugepagesize:       2048 kB
	// DirectMap4k:      434168 kB
	// DirectMap2M:      477184 kB
	// (could also run 'free', but easier to read a file than run a program)
	avail_physical_mem_kb = (U32Kilobytes)-1 ;
	avail_virtual_mem_kb = (U32Kilobytes)-1 ;

#else
	//do not know how to collect available memory info for other systems.
	//leave it blank here for now.

	avail_physical_mem_kb = (U32Kilobytes)-1 ;
	avail_virtual_mem_kb = (U32Kilobytes)-1 ;
#endif
}

void LLMemoryInfo::stream(std::ostream& s) const
{
	// We want these memory stats to be easy to grep from the log, along with
	// the timestamp. So preface each line with the timestamp and a
	// distinctive marker. Without that, we'd have to search the log for the
	// introducer line, then read subsequent lines, etc...
	std::string pfx(LLError::utcTime() + " <mem> ");

	// Max key length
	size_t key_width(0);
	for (const MapEntry& pair : inMap(mStatsMap))
	{
		size_t len(pair.first.length());
		if (len > key_width)
		{
			key_width = len;
		}
	}

	// Now stream stats
	for (const MapEntry& pair : inMap(mStatsMap))
	{
		s << pfx << std::setw(key_width+1) << (pair.first + ':') << ' ';
		LLSD value(pair.second);
		if (value.isInteger())
			s << std::setw(12) << value.asInteger();
		else if (value.isReal())
			s << std::fixed << std::setprecision(1) << value.asReal();
		else if (value.isDate())
			value.asDate().toStream(s);
		else
			s << value;           // just use default LLSD formatting
		s << std::endl;
	}
}

LLSD LLMemoryInfo::getStatsMap() const
{
	return mStatsMap;
}

LLMemoryInfo& LLMemoryInfo::refresh()
{
	mStatsMap = loadStatsMap();

	LL_DEBUGS("LLMemoryInfo") << "Populated mStatsMap:\n";
	LLSDSerialize::toPrettyXML(mStatsMap, LL_CONT);
	LL_ENDL;

	return *this;
}

LLSD LLMemoryInfo::loadStatsMap()
{
	// This implementation is derived from stream() code (as of 2011-06-29).
	Stats stats;

	// associate timestamp for analysis over time
	stats.add("timestamp", LLDate::now());

#if LL_WINDOWS
	MEMORYSTATUSEX state;
	state.dwLength = sizeof(state);
	GlobalMemoryStatusEx(&state);

	DWORDLONG div = 1024;

	stats.add("Percent Memory use", state.dwMemoryLoad/div);
	stats.add("Total Physical KB",  state.ullTotalPhys/div);
	stats.add("Avail Physical KB",  state.ullAvailPhys/div);
	stats.add("Total page KB",      state.ullTotalPageFile/div);
	stats.add("Avail page KB",      state.ullAvailPageFile/div);
	stats.add("Total Virtual KB",   state.ullTotalVirtual/div);
	stats.add("Avail Virtual KB",   state.ullAvailVirtual/div);

	PERFORMANCE_INFORMATION perf;
	perf.cb = sizeof(perf);
	GetPerformanceInfo(&perf, sizeof(perf));

	SIZE_T pagekb(perf.PageSize/1024);
	stats.add("CommitTotal KB",     perf.CommitTotal * pagekb);
	stats.add("CommitLimit KB",     perf.CommitLimit * pagekb);
	stats.add("CommitPeak KB",      perf.CommitPeak * pagekb);
	stats.add("PhysicalTotal KB",   perf.PhysicalTotal * pagekb);
	stats.add("PhysicalAvail KB",   perf.PhysicalAvailable * pagekb);
	stats.add("SystemCache KB",     perf.SystemCache * pagekb);
	stats.add("KernelTotal KB",     perf.KernelTotal * pagekb);
	stats.add("KernelPaged KB",     perf.KernelPaged * pagekb);
	stats.add("KernelNonpaged KB",  perf.KernelNonpaged * pagekb);
	stats.add("PageSize KB",        pagekb);
	stats.add("HandleCount",        perf.HandleCount);
	stats.add("ProcessCount",       perf.ProcessCount);
	stats.add("ThreadCount",        perf.ThreadCount);

	PROCESS_MEMORY_COUNTERS_EX pmem;
	pmem.cb = sizeof(pmem);
	// GetProcessMemoryInfo() is documented to accept either
	// PROCESS_MEMORY_COUNTERS* or PROCESS_MEMORY_COUNTERS_EX*, presumably
	// using the redundant size info to distinguish. But its prototype
	// specifically accepts PROCESS_MEMORY_COUNTERS*, and since this is a
	// classic-C API, PROCESS_MEMORY_COUNTERS_EX isn't a subclass. Cast the
	// pointer.
	GetProcessMemoryInfo(GetCurrentProcess(), PPROCESS_MEMORY_COUNTERS(&pmem), sizeof(pmem));

	stats.add("Page Fault Count",              pmem.PageFaultCount);
	stats.add("PeakWorkingSetSize KB",         pmem.PeakWorkingSetSize/div);
	stats.add("WorkingSetSize KB",             pmem.WorkingSetSize/div);
	stats.add("QutaPeakPagedPoolUsage KB",     pmem.QuotaPeakPagedPoolUsage/div);
	stats.add("QuotaPagedPoolUsage KB",        pmem.QuotaPagedPoolUsage/div);
	stats.add("QuotaPeakNonPagedPoolUsage KB", pmem.QuotaPeakNonPagedPoolUsage/div);
	stats.add("QuotaNonPagedPoolUsage KB",     pmem.QuotaNonPagedPoolUsage/div);
	stats.add("PagefileUsage KB",              pmem.PagefileUsage/div);
	stats.add("PeakPagefileUsage KB",          pmem.PeakPagefileUsage/div);
	stats.add("PrivateUsage KB",               pmem.PrivateUsage/div);

#elif LL_DARWIN
	vm_size_t page_size_kb;
	if (host_page_size(mach_host_self(), &page_size_kb) != KERN_SUCCESS)
	{
		LL_WARNS() << "Unable to get host page size. Using default value." << LL_ENDL;
		page_size_kb = 4096;
	}
	
	page_size_kb = page_size_kb / 1024;

	//
	// Collect the vm_stat's