一、CPU
使用proc文件系統,"proc文件系統是一個偽文件系統,它只存在內存當中,而不占用外存空間。它以文件系統的方式為訪問系統內核數據的操作提供接口。用戶和應用程序可以通過proc得到系統的信息,並可以改變內核的某些參數。"
從/proc文件系統獲取cpu使用情況: cat /proc/stat
在Linux的內核中,有一個全 局變量:Jiffies。 Jiffies代表時間。它的單位隨硬件平台的不同而不同。系統里定義了一個常數HZ,代表每秒種最小時間間隔的數目。這樣jiffies的單位就是 1/HZ。Intel平台jiffies的單位是1/100秒,這就是系統所能分辨的最小時間間隔了。每個CPU時間片,Jiffies都要加1。 CPU的利用率就是用執行用戶態+系統態的Jiffies除以總的Jifffies來表示。
[root@localhost LoadBalanceAlg]# cat /proc/stat
cpu 71095 55513 76751 2545622893 303185 4160 47722 0
cpu0 3855 1134 4284 159122519 3882 0 717 0
cpu1 4236 770 5837 159113370 11291 6 865 0
cpu2 4934 1142 5048 158991321 130622 362 2939 0
cpu3 2320 14774 5177 159111528 1417 8 1138 0
cpu4 2694 405 3086 159071174 56284 235 2477 0
cpu5 1701 886 2560 159129034 1316 2 849 0
cpu6 2937 450 2863 159068480 59183 228 2198 0
cpu7 916 316 2426 159130057 1682 1 933 0
cpu8 2543 50 3509 159122844 4467 1 2911 0
cpu9 4761 827 6296 159118849 4490 8 1086 0
cpu10 8517 4236 9148 159102063 9791 173 2382 0
cpu11 22001 29737 14602 159065992 2583 6 1382 0
cpu12 3453 150 3075 159113794 5387 1162 9276 0
cpu13 2120 424 3403 159126526 2608 7 1199 0
cpu14 2637 65 2663 159107796 6704 1914 14503 0
cpu15 1462 142 2763 159127539 1470 39 2859 0
intr 1636622296 1591605869 4 0 4 4 0 0 0 1 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 952 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1005479 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 32763528 0 0 0 0 0 0 0 1697776 0 0 0 0 0 0 0 1556158 2 0 0 0 0 0 0 1598011 0 0 0 0 0 0 0 1287622 0 0 0 0 0 0 0 1522517 0 0 0 0 0 0 0 2467360 0 0 0 0 0 0 0 1116999 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ctxt 431778894
btime 1363058934
processes 279394
procs_running 1
procs_blocked 0
CPU 以及CPU0、CPU1、CPU2、CPU3每行的每個參數意思(以第一行為例)為:
參數 解釋
user (432661) 從系統啟動開始累計到當前時刻,用戶態的CPU時間(單位:jiffies) ,不包含 nice值為負進程。1jiffies=0.01秒
nice (13295) 從系統啟動開始累計到當前時刻,nice值為負的進程所占用的CPU時間(單位:jiffies)
system (86656) 從系統啟動開始累計到當前時刻,核心時間(單位:jiffies)
idle (422145968) 從系統啟動開始累計到當前時刻,除硬盤IO等待時間以外其它等待時間(單位:jiffies)
iowait (171474) 從系統啟動開始累計到當前時刻,硬盤IO等待時間(單位:jiffies) ,
irq (233) 從系統啟動開始累計到當前時刻,硬中斷時間(單位:jiffies)
softirq (5346) 從系統啟動開始累計到當前時刻,軟中斷時間(單位:jiffies)
CPU時間=user+system+nice+idle+iowait+irq+softirq
“intr”這行給出中斷的信息,第一個為自系統啟動以來,發生的所有的中斷的次數;然后每個數對應一個特定的中斷自系統啟動以來所發生的次數。
“ctxt”給出了自系統啟動以來CPU發生的上下文交換的次數。
“btime”給出了從系統啟動到現在為止的時間,單位為秒。
“processes (total_forks) 自系統啟動以來所創建的任務的個數目。
“procs_running”:當前運行隊列的任務的數目。
“procs_blocked”:當前被阻塞的任務的數目。
public class Runtimeextends Object
每個 Java 應用程序都有一個 Runtime
類實例,使應用程序能夠與其運行的環境相連接。可以通過getRuntime
方法獲取當前運行時。
應用程序不能創建自己的 Runtime 類實例。
public abstract class Processextends Object
ProcessBuilder.start()
和Runtime.exec
方法創建一個本機進程,並返回 Process
子類的一個實例,該實例可用來控制進程並獲得相關信息。
<span style="font-size:14px;">import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.io.StringWriter; import org.apache.log4j.Logger; /** * 采集CPU使用率 */ public class CpuUsage extends ResourceUsage { private static Logger log = Logger.getLogger(CpuUsage.class); private static CpuUsage INSTANCE = new CpuUsage(); private CpuUsage(){ } public static CpuUsage getInstance(){ return INSTANCE; } /** * Purpose:采集CPU使用率 * @param args * @return float,CPU使用率,小於1 */ @Override public float get() { log.info("開始收集cpu使用率"); float cpuUsage = 0; Process pro1,pro2; Runtime r = Runtime.getRuntime(); try { String command = "cat /proc/stat"; //第一次采集CPU時間 long startTime = System.currentTimeMillis(); pro1 = r.exec(command); BufferedReader in1 = new BufferedReader(new InputStreamReader(pro1.getInputStream())); String line = null; long idleCpuTime1 = 0, totalCpuTime1 = 0; //分別為系統啟動后空閑的CPU時間和總的CPU時間 while((line=in1.readLine()) != null){ if(line.startsWith("cpu")){ line = line.trim(); log.info(line); String[] temp = line.split("\\s+"); idleCpuTime1 = Long.parseLong(temp[4]); for(String s : temp){ if(!s.equals("cpu")){ totalCpuTime1 += Long.parseLong(s); } } log.info("IdleCpuTime: " + idleCpuTime1 + ", " + "TotalCpuTime" + totalCpuTime1); break; } } in1.close(); pro1.destroy(); try { Thread.sleep(100); } catch (InterruptedException e) { StringWriter sw = new StringWriter(); e.printStackTrace(new PrintWriter(sw)); log.error("CpuUsage休眠時發生InterruptedException. " + e.getMessage()); log.error(sw.toString()); } //第二次采集CPU時間 long endTime = System.currentTimeMillis(); pro2 = r.exec(command); BufferedReader in2 = new BufferedReader(new InputStreamReader(pro2.getInputStream())); long idleCpuTime2 = 0, totalCpuTime2 = 0; //分別為系統啟動后空閑的CPU時間和總的CPU時間 while((line=in2.readLine()) != null){ if(line.startsWith("cpu")){ line = line.trim(); log.info(line); String[] temp = line.split("\\s+"); idleCpuTime2 = Long.parseLong(temp[4]); for(String s : temp){ if(!s.equals("cpu")){ totalCpuTime2 += Long.parseLong(s); } } log.info("IdleCpuTime: " + idleCpuTime2 + ", " + "TotalCpuTime" + totalCpuTime2); break; } } if(idleCpuTime1 != 0 && totalCpuTime1 !=0 && idleCpuTime2 != 0 && totalCpuTime2 !=0){ cpuUsage = 1 - (float)(idleCpuTime2 - idleCpuTime1)/(float)(totalCpuTime2 - totalCpuTime1); log.info("本節點CPU使用率為: " + cpuUsage); } in2.close(); pro2.destroy(); } catch (IOException e) { StringWriter sw = new StringWriter(); e.printStackTrace(new PrintWriter(sw)); log.error("CpuUsage發生InstantiationException. " + e.getMessage()); log.error(sw.toString()); } return cpuUsage; } /** * @param args * @throws InterruptedException */ public static void main(String[] args) throws InterruptedException { while(true){ System.out.println(CpuUsage.getInstance().get()); Thread.sleep(5000); } } }</span>

MemFree: 4109964 kB
Buffers: 35728 kB
Cached: 1877960 kB
SwapCached: 159088 kB
Active: 3184176 kB
Inactive: 672132 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 8167348 kB
LowFree: 4109964 kB
SwapTotal: 26738680 kB
SwapFree: 26373632 kB
Dirty: 40 kB
Writeback: 0 kB
AnonPages: 1872416 kB
Mapped: 24928 kB
Slab: 107804 kB
PageTables: 34612 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
CommitLimit: 30822352 kB
Committed_AS: 5386080 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 276892 kB
VmallocChunk: 34359460287 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
Hugepagesize: 2048 kB
<span style="font-size:14px;">import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.io.StringWriter; import org.apache.log4j.Logger; /** * 采集內存使用率 */ public class MemUsage extends ResourceUsage{ private static Logger log = Logger.getLogger(MemUsage.class); private static MemUsage INSTANCE = new MemUsage(); private MemUsage(){ } public static MemUsage getInstance(){ return INSTANCE; } /** * Purpose:采集內存使用率 * @param args * @return float,內存使用率,小於1 */ @Override public float get() { log.info("開始收集memory使用率"); float memUsage = 0.0f; Process pro = null; Runtime r = Runtime.getRuntime(); try { String command = "cat /proc/meminfo"; pro = r.exec(command); BufferedReader in = new BufferedReader(new InputStreamReader(pro.getInputStream())); String line = null; int count = 0; long totalMem = 0, freeMem = 0; while((line=in.readLine()) != null){ log.info(line); String[] memInfo = line.split("\\s+"); if(memInfo[0].startsWith("MemTotal")){ totalMem = Long.parseLong(memInfo[1]); } if(memInfo[0].startsWith("MemFree")){ freeMem = Long.parseLong(memInfo[1]); } memUsage = 1- (float)freeMem/(float)totalMem; log.info("本節點內存使用率為: " + memUsage); if(++count == 2){ break; } } in.close(); pro.destroy(); } catch (IOException e) { StringWriter sw = new StringWriter(); e.printStackTrace(new PrintWriter(sw)); log.error("MemUsage發生InstantiationException. " + e.getMessage()); log.error(sw.toString()); } return memUsage; } /** * @param args * @throws InterruptedException */ public static void main(String[] args) throws InterruptedException { while(true){ System.out.println(MemUsage.getInstance().get()); Thread.sleep(5000); } } }</span>

Linux 2.6.18-238.el5 (localhost.localdomain) 2013Äê03ÔÂ30ÈÕ
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sda 0.09 0.28 0.02 0.03 0.92 2.57 60.71 0.00 63.28 3.33 0.02
sda1 0.00 0.00 0.00 0.00 0.00 0.00 24.40 0.00 2.59 2.53 0.00
sda2 0.09 0.28 0.02 0.03 0.92 2.57 60.76 0.00 63.36 3.34 0.02
sdb 0.03 0.72 0.04 0.53 2.57 10.04 22.09 0.01 17.36 5.12 0.29
sdb1 0.03 0.72 0.04 0.53 2.57 10.04 22.09 0.01 17.36 5.12 0.29
dm-0 0.00 0.00 0.07 1.30 2.63 10.40 9.53 0.03 24.95 2.15 0.29
dm-1 0.00 0.00 0.11 0.28 0.86 2.21 8.00 0.12 300.47 0.16 0.01
<span style="font-size:14px;">import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.io.StringWriter; import org.apache.log4j.Logger; /** * 采集磁盤IO使用率 */ public class IoUsage extends ResourceUsage{ private static Logger log = Logger.getLogger(IoUsage.class); private static IoUsage INSTANCE = new IoUsage(); private IoUsage(){ } public static IoUsage getInstance(){ return INSTANCE; } /** * @Purpose:采集磁盤IO使用率 * @param args * @return float,磁盤IO使用率,小於1 */ @Override public float get() { log.info("開始收集磁盤IO使用率"); float ioUsage = 0.0f; Process pro = null; Runtime r = Runtime.getRuntime(); try { String command = "iostat -d -x"; pro = r.exec(command); BufferedReader in = new BufferedReader(new InputStreamReader(pro.getInputStream())); String line = null; int count = 0; while((line=in.readLine()) != null){ if(++count >= 4){ // log.info(line); String[] temp = line.split("\\s+"); if(temp.length > 1){ float util = Float.parseFloat(temp[temp.length-1]); ioUsage = (ioUsage>util)?ioUsage:util; } } } if(ioUsage > 0){ log.info("本節點磁盤IO使用率為: " + ioUsage); ioUsage /= 100; } in.close(); pro.destroy(); } catch (IOException e) { StringWriter sw = new StringWriter(); e.printStackTrace(new PrintWriter(sw)); log.error("IoUsage發生InstantiationException. " + e.getMessage()); log.error(sw.toString()); } return ioUsage; } /** * @param args * @throws InterruptedException */ public static void main(String[] args) throws InterruptedException { while(true){ System.out.println(IoUsage.getInstance().get()); Thread.sleep(5000); } } }</span>
Inter-| Receive | Transmit
face |bytes packets errs drop fifo frame compressed multicast|bytes packets errs drop fifo colls carrier compressed
lo:1402131426 15109136 0 0 0 0 0 0 1402131426 15109136 0 0 0 0 0 0
eth0:4546168400 42535979 0 0 0 0 0 44 5610190492 8943999 0 0 0 0 0 0
eth1: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
eth3: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
__tmp945063435: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
bond0:4546168400 42535979 0 0 0 0 0 44 5610190492 8943999 0 0 0 0 0 0
<span style="font-size:14px;">import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.io.StringWriter; import org.apache.log4j.Logger; /** * 采集網絡帶寬使用率 */ public class NetUsage extends ResourceUsage { private static Logger log = Logger.getLogger(NetUsage.class); private static NetUsage INSTANCE = new NetUsage(); private final static float TotalBandwidth = 1000; //網口帶寬,Mbps private NetUsage(){ } public static NetUsage getInstance(){ return INSTANCE; } /** * @Purpose:采集網絡帶寬使用率 * @param args * @return float,網絡帶寬使用率,小於1 */ @Override public float get() { log.info("開始收集網絡帶寬使用率"); float netUsage = 0.0f; Process pro1,pro2; Runtime r = Runtime.getRuntime(); try { String command = "cat /proc/net/dev"; //第一次采集流量數據 long startTime = System.currentTimeMillis(); pro1 = r.exec(command); BufferedReader in1 = new BufferedReader(new InputStreamReader(pro1.getInputStream())); String line = null; long inSize1 = 0, outSize1 = 0; while((line=in1.readLine()) != null){ line = line.trim(); if(line.startsWith("eth0")){ log.info(line); String[] temp = line.split("\\s+"); inSize1 = Long.parseLong(temp[0].substring(5)); //Receive bytes,單位為Byte outSize1 = Long.parseLong(temp[8]); //Transmit bytes,單位為Byte break; } } in1.close(); pro1.destroy(); try { Thread.sleep(1000); } catch (InterruptedException e) { StringWriter sw = new StringWriter(); e.printStackTrace(new PrintWriter(sw)); log.error("NetUsage休眠時發生InterruptedException. " + e.getMessage()); log.error(sw.toString()); } //第二次采集流量數據 long endTime = System.currentTimeMillis(); pro2 = r.exec(command); BufferedReader in2 = new BufferedReader(new InputStreamReader(pro2.getInputStream())); long inSize2 = 0 ,outSize2 = 0; while((line=in2.readLine()) != null){ line = line.trim(); if(line.startsWith("eth0")){ log.info(line); String[] temp = line.split("\\s+"); inSize2 = Long.parseLong(temp[0].substring(5)); outSize2 = Long.parseLong(temp[8]); break; } } if(inSize1 != 0 && outSize1 !=0 && inSize2 != 0 && outSize2 !=0){ float interval = (float)(endTime - startTime)/1000; //網口傳輸速度,單位為bps float curRate = (float)(inSize2 - inSize1 + outSize2 - outSize1)*8/(1000000*interval); netUsage = curRate/TotalBandwidth; log.info("本節點網口速度為: " + curRate + "Mbps"); log.info("本節點網絡帶寬使用率為: " + netUsage); } in2.close(); pro2.destroy(); } catch (IOException e) { StringWriter sw = new StringWriter(); e.printStackTrace(new PrintWriter(sw)); log.error("NetUsage發生InstantiationException. " + e.getMessage()); log.error(sw.toString()); } return netUsage; } /** * @param args * @throws InterruptedException */ public static void main(String[] args) throws InterruptedException { while(true){ System.out.println(NetUsage.getInstance().get()); Thread.sleep(5000); } } }</span>