获取内存和CPU使用率
我想获得总物理内存，CPU使用率和使用的内存量。 我查看了Runtime.freeMemory() ，但这不是整个系统的可用内存。
我知道我的回答迟到了，但我觉得这段代码很有意思。 这是对“封闭”代码的修改，应该在直接应用之前进行修改：
import java.io.BufferedReader; import java.io.InputStreamReader; import java.io.IOException; import java.lang.Process; import java.lang.Runtime; import java.util.HashMap; /** * SystemStatusReader is a collection of methods to read system status (cpu and memory) * * @author Andreu Correa Casablanca */ public class SystemStatusReader { public static final int CONSERVATIVE = 0; public static final int AVERAGE = 1; public static final int OPTIMISTIC = 2; /** * cpuUsage gives us the percentage of cpu usage * * mpstat -P ALL out stream example: * * Linux 3.2.0-30-generic (castarco-laptop) 10/09/12 _x86_64_ (2 CPU) - To discard * - To discard * 00:16:30 CPU %usr %nice %sys %iowait %irq %soft %steal %guest %idle - To discard * 00:16:30 all 17,62 0,03 3,55 0,84 0,00 0,03 0,00 0,00 77,93 * 00:16:30 0 17,36 0,05 3,61 0,83 0,00 0,05 0,00 0,00 78,12 * 00:16:30 1 17,88 0,02 3,49 0,86 0,00 0,01 0,00 0,00 77,74 * * @param measureMode Indicates if we want optimistic, convervative or average measurements. */ public static Double cpuUsage (int measureMode) throws Exception { BufferedReader mpstatReader = null; String mpstatLine; String[] mpstatChunkedLine; Double selected_idle; try { Runtime runtime = Runtime.getRuntime(); Process mpstatProcess = runtime.exec("mpstat -P ALL"); mpstatReader = new BufferedReader(new InputStreamReader(mpstatProcess.getInputStream())); // We discard the three first lines mpstatReader.readLine(); mpstatReader.readLine(); mpstatReader.readLine(); mpstatLine = mpstatReader.readLine(); if (mpstatLine == null) { throw new Exception("mpstat didn't work well"); } else if (measureMode == SystemStatusReader.AVERAGE) { mpstatChunkedLine = mpstatLine.replaceAll(",", ".").split("\\s+"); selected_idle = Double.parseDouble(mpstatChunkedLine[10]); } else { selected_idle = (measureMode == SystemStatusReader.CONSERVATIVE)?200.:0.; Double candidate_idle; int i = 0; while((mpstatLine = mpstatReader.readLine()) != null) { mpstatChunkedLine = mpstatLine.replaceAll(",", ".").split("\\s+"); candidate_idle = Double.parseDouble(mpstatChunkedLine[10]); if (measureMode == SystemStatusReader.CONSERVATIVE) { selected_idle = (selected_idle < candidate_idle)?selected_idle:candidate_idle; } else if (measureMode == SystemStatusReader.OPTIMISTIC) { selected_idle = (selected_idle > candidate_idle)?selected_idle:candidate_idle; } ++i; } if (i == 0) { throw new Exception("mpstat didn't work well"); } } } catch (Exception e) { throw e; // It's not desirable to handle the exception here } finally { if (mpstatReader != null) try { mpstatReader.close(); } catch (IOException e) { // Do nothing } } return 100-selected_idle; } /** * memoryUsage gives us data about memory usage (RAM and SWAP) */ public static HashMap memoryUsage () throws Exception { BufferedReader freeReader = null; String freeLine; String[] freeChunkedLine; HashMap usageData = new HashMap(); try { Runtime runtime = Runtime.getRuntime(); Process freeProcess = runtime.exec("free -k"); // We measure memory in kilobytes to obtain a greater granularity freeReader = new BufferedReader(new InputStreamReader(freeProcess.getInputStream())); // We discard the first line freeReader.readLine(); freeLine = freeReader.readLine(); if (freeLine == null) { throw new Exception("free didn't work well"); } freeChunkedLine = freeLine.split("\\s+"); usageData.put("total", Integer.parseInt(freeChunkedLine[1])); freeLine = freeReader.readLine(); if (freeLine == null) { throw new Exception("free didn't work well"); } freeChunkedLine = freeLine.split("\\s+"); usageData.put("used", Integer.parseInt(freeChunkedLine[2])); freeLine = freeReader.readLine(); if (freeLine == null) { throw new Exception("free didn't work well"); } freeChunkedLine = freeLine.split("\\s+"); usageData.put("swap_total", Integer.parseInt(freeChunkedLine[1])); usageData.put("swap_used", Integer.parseInt(freeChunkedLine[2])); } catch (Exception e) { throw e; } finally { if (freeReader != null) try { freeReader.close(); } catch (IOException e) { // Do nothing } } return usageData; } }
您可以使用SIGAR（http://support.hyperic.com/display/SIGAR/Home）。 我相信这是跨平台的（我只在Windows上尝试过），我知道它有效（因为我已经尝试过了）。
Javadoc： http ： //www.hyperic.com/support/docs/sigar/
二进制文件： http ： //support.hyperic.com/display/SIGAR/Home#Home-binaries
内存和CPU 。
CPU示例：
static final ThreadMXBean threadBean = ManagementFactory.getThreadMXBean(); ... long start = threadBean.getCurrentThreadCpuTime(); for (int i = 0; i < 10000000; i++) { ... } long finish = threadBean.getCurrentThreadCpuTime();
在Linux上，您可以将/ proc / meminfo作为文本文件打开并解析结果。
如果是交互式使用，请通过’jconsole’使用JMX。 它显示了很好的实时图表和许多其他诊断信息。