一：背景
置信很多人都晓得通过 工作管理器 抓取dump，尽管简略粗犷，但无奈满足程序的无数种死法，比方：
- 内存收缩，程序爆炸
- CPU爆高，程序累死
- 利用无响应，用户气死
- 意外退出，和人生一样
既然手工太弱鸡，那有什么好的工具呢？ 除了 adplus，本文举荐一款神器 procdump, 下载地址：https://docs.microsoft.com/zh... ,还能反对 linux ，具体怎么装置就不细说了。
二：内存收缩，程序爆炸
内存收缩 这种状况我置信很有敌人都遇到过，我见过最多的案例就是用了小缓存 static，而后有意无意的遗记开释，导致有限沉积终爆炸，那这种怎么用 procdump 去抓呢？
为了不便演示，我先写一个有限分配内存的例子。
static void Main(string[] args) { List<string> list = new List<string>(); for (int i = 0; i < int.MaxValue; i++) { list.Add(string.Join(",", Enumerable.Range(0, 10000))); } Console.ReadLine(); }将程序跑起来后，设置 procdump 在内存超过 1G 的时候主动抓取全内存 dump，应用如下命令.
C:\Windows\system32>procdump ConsoleApp2 -m 1024 -ma E:\net5\ConsoleApp1\ConsoleApp2\bin\DebugProcDump v10.0 - Sysinternals process dump utilityCopyright (C) 2009-2020 Mark Russinovich and Andrew RichardsSysinternals - www.sysinternals.comProcess: ConsoleApp2.exe (24112)Process image: E:\net5\ConsoleApp1\ConsoleApp2\bin\Debug\ConsoleApp2.exeCPU threshold: n/aPerformance counter: n/aCommit threshold: >= 1024 MBThreshold seconds: 10Hung window check: DisabledLog debug strings: DisabledException monitor: DisabledException filter: [Includes] * [Excludes]Terminate monitor: DisabledCloning type: DisabledConcurrent limit: n/aAvoid outage: n/aNumber of dumps: 1Dump folder: E:\net5\ConsoleApp1\ConsoleApp2\bin\Debug\Dump filename/mask: PROCESSNAME_YYMMDD_HHMMSSQueue to WER: DisabledKill after dump: DisabledPress Ctrl-C to end monitoring without terminating the process.[21:23:43] Commit: 1087Mb[21:23:43] Dump 1 initiated: E:\net5\ConsoleApp1\ConsoleApp2\bin\Debug\ConsoleApp2.exe_210323_212343.dmp[21:23:43] Dump 1 writing: Estimated dump file size is 1179 MB.[21:23:44] Dump 1 complete: 1179 MB written in 1.3 seconds[21:23:44] Dump count reached.从最初五行能够看出，当内存达到 1087M 的时候主动生成了 dump 文件，接下来用 windbg 看一看。
- 查看以后 process 的内存占用量，应用
!address -summary即可
0:000> !address -summary Mapping file section regions...Mapping module regions...Mapping PEB regions...Mapping TEB and stack regions...Mapping heap regions...Mapping page heap regions...Mapping other regions...Mapping stack trace database regions...Mapping activation context regions...--- Usage Summary ---------------- RgnCount ----------- Total Size -------- %ofBusy %ofTotalFree 63 b30b4000 ( 2.798 GB) 69.94%<unknown> 228 48547000 ( 1.130 GB) 93.99% 28.25%Image 210 4115000 ( 65.082 MB) 5.29% 1.59%Stack 21 700000 ( 7.000 MB) 0.57% 0.17%Heap 12 170000 ( 1.438 MB) 0.12% 0.04%Other 7 5a000 ( 360.000 kB) 0.03% 0.01%TEB 7 13000 ( 76.000 kB) 0.01% 0.00%PEB 1 3000 ( 12.000 kB) 0.00% 0.00%--- Type Summary (for busy) ------ RgnCount ----------- Total Size -------- %ofBusy %ofTotalMEM_PRIVATE 250 47121000 ( 1.110 GB) 92.36% 27.76%MEM_IMAGE 217 411e000 ( 65.117 MB) 5.29% 1.59%MEM_MAPPED 19 1cfd000 ( 28.988 MB) 2.35% 0.71%--- State Summary ---------------- RgnCount ----------- Total Size -------- %ofBusy %ofTotalMEM_FREE 63 b30b4000 ( 2.798 GB) 69.94%MEM_COMMIT 357 47f12000 ( 1.124 GB) 93.49% 28.10%MEM_RESERVE 129 502a000 ( 80.164 MB) 6.51% 1.96%--- Protect Summary (for commit) - RgnCount ----------- Total Size -------- %ofBusy %ofTotalPAGE_READWRITE 177 437d5000 ( 1.055 GB) 87.70% 26.36%PAGE_EXECUTE_READ 35 33c7000 ( 51.777 MB) 4.21% 1.26%PAGE_READONLY 90 c41000 ( 12.254 MB) 1.00% 0.30%PAGE_WRITECOPY 34 70b000 ( 7.043 MB) 0.57% 0.17%PAGE_READWRITE|PAGE_GUARD 14 23000 ( 140.000 kB) 0.01% 0.00%PAGE_EXECUTE_READWRITE 7 7000 ( 28.000 kB) 0.00% 0.00%--- Largest Region by Usage ----------- Base Address -------- Region Size ----------Free 80010000 7f130000 ( 1.986 GB)<unknown> 438e1000 200f000 ( 32.059 MB)Image 660e0000 f55000 ( 15.332 MB)Stack e00000 fd000 (1012.000 kB)Heap c97000 98000 ( 608.000 kB)Other ff2c0000 33000 ( 204.000 kB)TEB 990000 3000 ( 12.000 kB)PEB 98d000 3000 ( 12.000 kB)看到下面 PAGE_READWRITE 行的 (1.055 GB) 吗？ 和方才 Console 中的 1087M 一唱一和，没故障。
- 寻找大对象，在托管堆中应用
!dumpheap -stat -min 1024即可
||0:0:000> !dumpheap -stat -min 1024Statistics: MT Count TotalSize Class Name65d42788 2 13044 System.Object[]65d42d74 2 98328 System.String[]65d42c60 73 1082988 System.Char[]65d424e4 11452 1119913984 System.String从输入的最初一行能够看出，System.String 有1w多个，接下来能够减少 -type 属性筛选出 >10k 的字符串。
0:000> !dumpheap -type System.String -min 10240 Address MT Size03c75568 65d424e4 97792 03c8d378 65d424e4 97792 4a855060 65d424e4 97792 Statistics: MT Count TotalSize Class Name65d424e4 11452 1119913984 System.StringTotal 11452 objects0:000> !gcroot 4a855060Thread 36e4:*** WARNING: Unable to verify checksum for ConsoleApp2.exe 00b3f358 012108d1 ConsoleApp2.Program.Main(System.String[]) [E:\net5\ConsoleApp1\ConsoleApp2\Program.cs @ 18] ebp+18: 00b3f370 -> 02c71fd8 System.Collections.Generic.List`1[[System.String, mscorlib]] -> 02cce2ec System.String[] -> 4a855060 System.StringFound 1 unique roots (run '!GCRoot -all' to see all roots).从最初的 !gcroot 看，的确是被 Program.cs:18 行的 List 所持有，到此上不着天;下不着地。
三：CPU爆高，程序累死
说起CPU爆高的案例，我发现更多的是在 非托管堆 上，比方GC回收，争抢锁等，很少有人能傻到在 托管层 上把cpu搞起来。
对了，剖析CPU 爆高有一个小技巧，那就是间断抓 dump 快照，看两个 dump 中的线程运行状况，这时候就非常适合 procdump，先来看测试代码。
class Program { static void Main(string[] args) { Parallel.For(0, int.MaxValue, (i) => { while (true) { } }); Console.ReadLine(); } }当初我设定 间断 5s 内 CPU 超过 70% 抓取 dump，直到 2 个为止 。
C:\Windows\system32>procdump ConsoleApp2 -s 5 -n 2 -c 70 E:\net5\ConsoleApp1\ConsoleApp2\bin\DebugProcDump v10.0 - Sysinternals process dump utilityCopyright (C) 2009-2020 Mark Russinovich and Andrew RichardsSysinternals - www.sysinternals.comProcess: ConsoleApp2.exe (22152)Process image: E:\net5\ConsoleApp1\ConsoleApp2\bin\Debug\ConsoleApp2.exeCPU threshold: >= 70% of systemPerformance counter: n/aCommit threshold: n/aThreshold seconds: 5Hung window check: DisabledLog debug strings: DisabledException monitor: DisabledException filter: [Includes] * [Excludes]Terminate monitor: DisabledCloning type: DisabledConcurrent limit: n/aAvoid outage: n/aNumber of dumps: 2Dump folder: E:\net5\ConsoleApp1\ConsoleApp2\bin\Debug\Dump filename/mask: PROCESSNAME_YYMMDD_HHMMSSQueue to WER: DisabledKill after dump: DisabledPress Ctrl-C to end monitoring without terminating the process.[22:25:47] CPU: 95% 1s[22:25:48] CPU: 100% 2s[22:25:50] CPU: 96% 3s[22:25:51] CPU: 98% 4s[22:25:52] CPU: 99% 5s (Trigger)[22:25:53] Dump 1 initiated: E:\net5\ConsoleApp1\ConsoleApp2\bin\Debug\ConsoleApp2.exe_210323_222553.dmp[22:25:54] Dump 1 complete: 5 MB written in 0.3 seconds[22:25:56] CPU: 88% 1s[22:25:58] CPU: 93% 2s[22:26:00] CPU: 89% 3s[22:26:02] CPU: 89% 4s[22:26:04] CPU: 95% 5s (Trigger)[22:26:05] Dump 2 initiated: E:\net5\ConsoleApp1\ConsoleApp2\bin\Debug\ConsoleApp2.exe_210323_222605.dmp[22:26:06] Dump 2 complete: 5 MB written in 0.4 seconds[22:26:07] Dump count reached.从最初输入中能够看到，间断 5s CPU 超过了 70% 抓取了 dump，总共来了2个。
当初 dump 有了，接下来用两个 windbg 实例关上，验证下 dump 的生成工夫，如下图所示：
从图中能够看到，两个 dump 生成工夫相隔 12s，而且通过 !runaway 发现上面的线程：
- 14:2cb8
- 19:3f8c
- ...
都运行了长达 10s ，这阐明什么？阐明这二个线程应该在某个中央死循环了。。。对吧。。。
切到 14 号线程通过 !clrstack 看调用堆栈即可，都是死在 ConsoleApp2.Program+c.b__0_0(Int32) 这里出不来。。。
四：总结
感觉篇幅有点长了，就先说到这里吧，有趣味的话，能够把 procdump 拉下来玩一玩 。