纯PHP实现系统与PHP进程监控：深入探索/proc文件系统

<?php
function getSystemLoadAvg() {
    if (file_exists('/proc/loadavg')) {
        $loadavg_content = file_get_contents('/proc/loadavg');
        $parts = explode(' ', $loadavg_content);
        return [
            '1_min' => (float)$parts[0],
            '5_min' => (float)$parts[1],
            '15_min' => (float)$parts[2]
        ];
    }
    return null;
}

// $load = getSystemLoadAvg();
// if ($load) {
//     echo "System Load (1/5/15 min): {$load['1_min']} / {$load['5_min']} / {$load['15_min']}\n";
// }
?>

<?php
function getSystemMemoryInfo() {
    $memoryInfo = [];
    if (file_exists('/proc/meminfo')) {
        $meminfo_content = file_get_contents('/proc/meminfo');
        $lines = explode("\n", $meminfo_content);
        foreach ($lines as $line) {
            if (preg_match('/^(\w+):\s*(\d+)\s*kB$/', $line, $matches)) {
                $key = strtolower($matches[1]);
                $memoryInfo[$key] = (int)$matches[2]; // Value in KB
            }
        }
    }
    return $memoryInfo;
}

// $mem = getSystemMemoryInfo();
// if ($mem) {
//     echo "Total Memory: " . round($mem['memtotal'] / 1024 / 1024, 2) . " GB\n";
//     echo "Available Memory: " . round($mem['memavailable'] / 1024 / 1024, 2) . " GB\n";
// }
?>

<?php
/**
 * 获取当前系统上所有PHP进程的概览信息。
 * 仅适用于Linux系统，依赖于/proc文件系统。
 *
 * @return array 包含PHP进程总数、用户数、长时间运行进程数、总内存占用等信息的数组，
 *               或在出错时返回包含'error'键的数组。
 */
function getPhpProcessOverview() {
    $phpProcesses = [];
    $totalPhpMemoryKb = 0; // 所有PHP进程的VmRSS总和，单位KB
    $usersRunningPhp = []; // 存储运行PHP进程的用户UID
    $longRunningProcessesCount = 0; // 运行时间超过5分钟的PHP进程数量

    // 检查/proc文件系统是否存在，此功能为Linux特有
    if (!is_dir('/proc')) {
        return ['error' => '`/proc` filesystem not found. This feature is Linux-specific.'];
    }

    // 获取所有PID目录
    $pids = array_filter(scandir('/proc'), 'is_numeric');

    // 获取系统启动时间 (btime) 和时钟频率 (_SC_CLK_TCK)
    $systemBootTime = 0;
    $clockTicks = 100; // 常见的_SC_CLK_TCK值，通常为100 jiffies/秒
    if (file_exists('/proc/stat')) {
        $statFileContent = file_get_contents('/proc/stat');
        if (preg_match('/^btime\s*(\d+)/m', $statFileContent, $btimeMatches)) {
            $systemBootTime = (int)$btimeMatches[1];
        }
    }

    foreach ($pids as $pid) {
        $cmdlinePath = "/proc/{$pid}/cmdline";
        $statusPath = "/proc/{$pid}/status";
        $statPath = "/proc/{$pid}/stat";

        // 确保文件存在且可读
        if (file_exists($cmdlinePath) && file_exists($statusPath) && file_exists($statPath)) {
            $cmdline = file_get_contents($cmdlinePath);
            // cmdline内容通常以null字节分隔，替换为空格以便解析
            $cmdline = str_replace("\0", " ", $cmdline);

            // 通过命令行判断是否为PHP进程 (php, php-fpm, php-cgi等)
            if (preg_match('/php(?:-fpm|-cgi)?/i', $cmdline)) {
                $statusContent = file_get_contents($statusPath);
                $statContent = file_get_contents($statPath);

                $processInfo = [
                    'pid' => (int)$pid,
                    'name' => '',
                    'memory_rss_kb' => 0, // Resident Set Size (物理内存占用)
                    'uid' => '',
                    'uptime_seconds' => 0,
                    'cmdline' => trim($cmdline)
                ];

                // 解析status文件获取进程名、VmRSS和UID
                if (preg_match('/^Name:\s*(.*)$/m', $statusContent, $matches)) {
                    $processInfo['name'] = trim($matches[1]);
                }
                if (preg_match('/^VmRSS:\s*(\d+)\s*kB$/m', $statusContent, $matches)) {
                    $processInfo['memory_rss_kb'] = (int)$matches[1];
                    $totalPhpMemoryKb += (int)$matches[1];
                }
                if (preg_match('/^Uid:\s*(\d+)/m', $statusContent, $matches)) {
                    $processInfo['uid'] = $matches[1];
                    $usersRunningPhp[$matches[1]] = true; // 记录运行进程的用户
                }

                // 解析stat文件获取进程启动时间并计算运行时长
                // /proc/[PID]/stat 的第22个字段 (0-indexed 21) 是进程启动时间 (starttime)
                $statFields = explode(' ', $statContent);
                if (isset($statFields[21]) && $systemBootTime > 0) {
                    $startTimeJiffies = (int)$statFields[21];
                    // 进程启动时间（秒） = 系统启动时间（秒） + 进程启动时钟节拍 / 每秒时钟节拍
                    $processStartTimeSeconds = $systemBootTime + ($startTimeJiffies / $clockTicks);
                    $processUptimeSeconds = time() - $processStartTimeSeconds;
                    $processInfo['uptime_seconds'] = max(0, round($processUptimeSeconds));

                    // 判断是否为长时间运行进程 (例如，超过5分钟)
                    if ($processInfo['uptime_seconds'] > (5 * 60)) {
                        $longRunningProcessesCount++;
                    }
                }

                $phpProcesses[] = $processInfo;
            }
        }
    }

    return [
        'total_scripts_running' => count($phpProcesses),
        'users_running_process' => count($usersRunningPhp),
        'process_with_more_than_5_minutes' => $longRunningProcessesCount,
        'memory_global_assigned_to_all_php_kb' => $totalPhpMemoryKb,
        'details' => $phpProcesses // 包含每个PHP进程的详细信息
    ];
}

// 示例用法：
$overview = getPhpProcessOverview();

if (isset($overview['error'])) {
    echo "Error: " . $overview['error'] . "\n";
} else {
    echo "--- PHP 进程概览 ---\n";
    echo "总计运行中的PHP进程数: " . $overview['total_scripts_running'] . "\n";
    echo "运行PHP进程的用户数: " . $overview['users_running_process'] . "\n";
    echo "运行时间超过5分钟的PHP进程数: " . $overview['process_with_more_than_5_minutes'] . "\n";
    echo "所有PHP进程占用的总物理内存 (RSS): " . round($overview['memory_global_assigned_to_all_php_kb'] / 1024, 2) . " MB\n";
    echo "\n---