<\/p>\r\n
<\/p>\r\n
Bizler ise developer’lar olarak, en az\u0131ndan uygulamalar\u0131m\u0131z\u0131n neden beklenmedik \u015fekilde davrand\u0131klar\u0131n\u0131 anlayabilecek kadar dump analizlerini yapabiliyor olmam\u0131z gerekmektedir.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Daha \u00f6nce benzer konular \u00fczerinde farkl\u0131 makaleler yazm\u0131\u015f ve sunumlar ger\u00e7ekle\u015ftirmi\u015ftim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
- \r\n
- dotnetKonf Etkinli\u011fi \u2013 Debugging and Profiling .NET Core Applications on Linux<\/a><\/li>\r\n
- .NET Core Uygulamalar\u0131n\u0131n Linux \u00dczerinde Debugging & Profiling \u0130\u015flemlerine Genel Bak\u0131\u015f \u2013 1 (Perf, LTTNg)<\/a><\/li>\r\n
- WinDBG ile Dump Analizi Yaparak Performans Sorunlar\u0131n\u0131 \u00c7\u00f6z\u00fcmleme<\/a><\/li>\r\n<\/ul>\r\n
<\/p>\r\n
<\/p>\r\n
Bu makale kapsam\u0131nda ise kubernetes<\/strong> ortam\u0131nda \u00e7al\u0131\u015fan hem windows-based<\/strong> hem de linux-based<\/strong> container’lar\u0131m\u0131zdan nas\u0131l dump<\/strong> alabilece\u011fimizi ve en basit \u015fekilde windows<\/em> \u00fczerinde nas\u0131l analiz edebilece\u011fimizi g\u00f6stermeye \u00e7al\u0131\u015faca\u011f\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Senaryo<\/h2>\r\n
<\/p>\r\n
<\/p>\r\n
Azure Kubernetes Service<\/em>‘i \u00fczerine deploy etti\u011fimiz bir uygulaman\u0131n, bir s\u00fcre sonra memory leak<\/strong> sebebi ile crash oldu\u011funu varsayal\u0131m. Bu memory leak’in nereden kaynakland\u0131\u011f\u0131n\u0131 h\u0131zl\u0131 bir \u015fekilde ara\u015ft\u0131rabilmek i\u00e7in ise, ilgili uygulaman\u0131n memory dump’\u0131n\u0131 incelemeye karar verdi\u011fimizi d\u00fc\u015f\u00fcnelim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Bu senaryonun d\u0131\u015f\u0131nda uygulamalar\u0131m\u0131z belirli bir zaman sonra hang<\/strong> oluyor veya bilinmedik problemlerden dolay\u0131 deadlock’lar<\/strong>, exception’lar<\/strong> \u00fcretip crash<\/strong> de oluyor olabilir. Bunlar gibi \u00e7e\u015fitli problemleri adresleyebilmek i\u00e7in uygulamalar\u0131n o anki memory dump’lar\u0131n\u0131 alarak, kolay bir \u015fekilde bilgi sahibi olabiliriz<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Ben h\u0131zl\u0131 bir \u00f6rnek ger\u00e7ekle\u015ftirebilmek ad\u0131na a\u015fa\u011f\u0131daki gibi memory \u00fczerinde allocation ger\u00e7ekle\u015ftirecek basit bir kod blo\u011fu haz\u0131rlad\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
using System;\r\nusing System.Collections.Generic;\r\nusing System.Threading;\r\n\r\nnamespace MemoryLeakNETFramework\r\n{\r\n\tclass Program\r\n\t{\r\n\t\tstatic void Main(string[] args)\r\n\t\t{\r\n\t\t\tConsole.WriteLine(\"App started.\");\r\n\r\n\t\t\tvar productService = new ProductService();\r\n\t\t\tproductService.GetProducts();\r\n\r\n\t\t\twhile (true)\r\n\t\t\t{\r\n\t\t\t\tThread.Sleep(TimeSpan.FromMinutes(1));\r\n\t\t\t}\r\n\t\t}\r\n\t}\r\n\r\n\tclass ProductDTO\r\n\t{\r\n\t\tpublic int Id { get; set; }\r\n\t\tpublic byte[] XParameter { get; set; }\r\n\t}\r\n\r\n\tstatic class ProductUtil\r\n\t{\r\n\t\tpublic static byte[] CalculateSomething()\r\n\t\t{\r\n\t\t\tbyte[] buffer = new byte[1024];\r\n\t\t\treturn buffer;\r\n\t\t}\r\n\t}\r\n\r\n\tclass ProductService\r\n\t{\r\n\t\tpublic List GetProducts()\r\n\t\t{\r\n\t\t\tList<ProductDTO> products = new List<ProductDTO>();\r\n\r\n\t\t\tfor (int i = 0; i < 500000; i++)\r\n\t\t\t{\r\n\t\t\t\tvar product = new ProductDTO()\r\n\t\t\t\t{\r\n\t\t\t\t\tId = i,\r\n\t\t\t\t\tXParameter = ProductUtil.CalculateSomething()\r\n\t\t\t\t};\r\n\r\n\t\t\t\tproducts.Add(product);\r\n\t\t\t}\r\n\r\n\t\t\treturn products;\r\n\t\t}\r\n\t}\r\n}<\/pre>\r\n<\/p>\r\n
<\/p>\r\n
G\u00f6rd\u00fc\u011f\u00fcm\u00fcz gibi \u00fcr\u00fcn listesinin “ProductDTO<\/em>” class’\u0131na mapping i\u015flemi s\u0131ras\u0131nda bir allocation i\u015flemi ger\u00e7ekle\u015ftiriyorum.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Ger\u00e7ek d\u00fcnyada ise a\u015fa\u011f\u0131daki gibi \u00e7e\u015fitli sebeplerden dolay\u0131 memory leak problemleri ile kar\u015f\u0131la\u015fabilmemiz m\u00fcmk\u00fcnd\u00fcr.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
- \r\n
- Dispose edilmeyen unmanaged resource’lar<\/li>\r\n
- In-memory caching<\/li>\r\n
- Yanl\u0131\u015f thread kullan\u0131mlar\u0131<\/li>\r\n
- Closure allocation’lar\u0131<\/li>\r\n
- Yanl\u0131\u015f static durumlar\u0131<\/li>\r\n<\/ul>\r\n
<\/p>\r\n
<\/p>\r\n
Windows Container ile Dump Almaya Ba\u015flayal\u0131m<\/h2>\r\n
<\/p>\r\n
<\/p>\r\n
\u0130lk olarak windows-based <\/em>bir container i\u00e7erisinde \u00e7al\u0131\u015fan uygulamam\u0131z\u0131n, memory dump’\u0131n\u0131 nas\u0131l alabilece\u011fimiz konusuna de\u011finelim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
x86 .NET Framework<\/em> 4.8<\/em> uygulamas\u0131n\u0131 containerize edebilmek i\u00e7in ise, a\u015fa\u011f\u0131daki “Dockerfile<\/em>” dosyas\u0131n\u0131 kulland\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
FROM mcr.microsoft.com\/dotnet\/framework\/runtime:4.8-windowsservercore-ltsc2019\r\nWORKDIR \/app\r\nCOPY . .\r\nENTRYPOINT [\"C:\\\\app\\\\MemoryLeakNETFramework.exe\"]\r\n<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
\u015eimdi ilk olarak a\u015fa\u011f\u0131daki komutlar\u0131 \u00e7al\u0131\u015ft\u0131ral\u0131m ve deploy etmi\u015f oldu\u011fumuz uygulamaya bir bakal\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
kubectl get pod\r\nkubectl top pod<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n![\"\"](\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\")
<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
G\u00f6rd\u00fc\u011f\u00fcm\u00fcz gibi ilgili uygulama \u015fuan 579Mi<\/strong> civar\u0131nda bir memory kullan\u0131m\u0131 ger\u00e7ekle\u015ftirmekte. Bu kullan\u0131m\u0131n ise zamanla artt\u0131\u011f\u0131n\u0131 ve ilgili uygulaman\u0131n crash olmas\u0131na neden oldu\u011funu varsay\u0131yoruz. \u015eimdi ilgili uygulama crash olmadan \u00f6nce pod’unun i\u00e7erisine girelim ve memory dump alma i\u015flemini ger\u00e7ekle\u015ftirelim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
\u00d6ncelikle windows<\/em> container’\u0131n powershell session’\u0131na girebilmek i\u00e7in a\u015fa\u011f\u0131daki komutu \u00e7al\u0131\u015ft\u0131ral\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
kubectl exec -it YOUR_POD_NAME -- powershell<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
Memory dump alma i\u015flemini ger\u00e7ekle\u015ftirebilmek i\u00e7in ise, ProcDump<\/em> tool’unu kullanaca\u011f\u0131z. ProcDump <\/em>command-line \u00fczerinden kolayca dump’lar alabilmemize olanak sa\u011flayan bir tool’dur.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
\u015eimdi iligli pod’un powershell session’\u0131na girdikten sonra, ProcDump<\/em> tool’unu a\u015fa\u011f\u0131daki komut yard\u0131m\u0131yla ilgili pod’un i\u00e7erisine download edelim ve ard\u0131ndan ilgili zip dosyas\u0131 i\u00e7erisinden \u00e7\u0131kartal\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
PS C:\\app> Invoke-WebRequest -UseBasicParsing -Uri https:\/\/download.sysinternals.com\/files\/Procdump.zip -OutFile C:\\app\\procdump.zip\r\n\r\nPS C:\\app> Expand-Archive .\\procdump.zip<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
\u015eimdi ise dump almak istedi\u011fimiz uygulaman\u0131n process ID<\/em> bilgisine ihtiyac\u0131m\u0131z var. Bunun i\u00e7in “Get-Process<\/em>” komutunu \u00e7al\u0131\u015ft\u0131ral\u0131m ve ilgili process’in ID<\/em> bilgisini kopyalayal\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Ard\u0131ndan “procdump<\/em>” klas\u00f6r\u00fcne girelim ve a\u015fa\u011f\u0131daki komutu \u00e7al\u0131\u015ft\u0131rarak dump alma i\u015flemini ger\u00e7ekle\u015ftirelim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
.\\procdump.exe -ma YOUR_PROCESS_ID -s 5 -n 1 -accepteula<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
Burada dikkat etmemiz gereken \u00f6nemli nokta, uygulaman\u0131n “x86<\/em>” veya “x64<\/em>” olarak hangi hedef platform’da \u00e7al\u0131\u015ft\u0131\u011f\u0131n\u0131 belirtmektir. E\u011fer uygulama “x64<\/em>” olarak \u00e7al\u0131\u015f\u0131yorsa, dump al\u0131rken “-64<\/em>” parametresinin eklenmesi yeterli olacakt\u0131r. Default “x86<\/em>” olarak i\u015flem ger\u00e7ekle\u015ftirmektedir.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
Yukar\u0131daki komut k\u0131saca, “5<\/em>” saniye gibi bir s\u00fcre ile bir adet full process dump alma i\u015flemi ger\u00e7ekle\u015ftirdi.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Full process dump’\u0131 ald\u0131\u011f\u0131m\u0131z i\u00e7in dump dosyas\u0131n\u0131n boyutu da bi hayli b\u00fcy\u00fck. Fakat bir \u00e7ok durum i\u00e7in full dump almak hayat kurtar\u0131c\u0131 olabiliyor.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
\u015eimdi a\u015fa\u011f\u0131daki komut yard\u0131m\u0131 ile ilgili dump dosyas\u0131n\u0131 s\u0131k\u0131\u015ft\u0131ral\u0131m. B\u00f6ylece ilgili dump dosyas\u0131n\u0131 daha h\u0131zl\u0131 bir \u015fekilde pod i\u00e7erisinden kendi lokal ortam\u0131m\u0131za kopyalayabiliriz.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
PS C:\\app\\procdump> Compress-Archive .\\MemoryLeakNETFramework.exe_220610_144815.dmp .\\mydump.zip<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
S\u0131k\u0131\u015ft\u0131rma i\u015flemi tamamland\u0131\u011f\u0131na g\u00f6re, ilgili “mydump.zip<\/em>” dosyas\u0131n\u0131 kendi lokal ortam\u0131m\u0131za kopyalayabiliriz. Bunun i\u00e7in kendi lokal ortam\u0131m\u0131z \u00fczerinde “C:\\<\/em>” dizini alt\u0131na gelelim. Ar\u0131ndan a\u015fa\u011f\u0131daki komut ile kopyalama i\u015flemini ger\u00e7ekle\u015ftirelim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
kubectl cp YOUR_POD_NAME:\/app\/procdump\/mydump.zip .\/procdump\/mydump.zip<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
G\u00f6rd\u00fc\u011f\u00fcm\u00fcz gibi ilgili dump dosyas\u0131, “C:\\procdump<\/em>” dizini alt\u0131na kopyalanm\u0131\u015f durumda.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Linux Container \u0130\u00e7erisinden Dump Alal\u0131m<\/h2>\r\n
<\/p>\r\n
<\/p>\r\n
Linux<\/em> container ile \u00f6rnek ger\u00e7ekle\u015ftirebilmek i\u00e7in ise ayn\u0131 kod blo\u011funu .NET 6<\/strong><\/em> ile containerize bir hale getirdim ve linux-based<\/em> bir nodepool’a deployment i\u015flemini ger\u00e7ekle\u015ftirdim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Containerize edebilmek i\u00e7in ise a\u015fa\u011f\u0131daki “Dockerfile<\/em>” \u0131 kulland\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
FROM mcr.microsoft.com\/dotnet\/runtime:6.0-focal AS base\r\nWORKDIR \/app\r\n\r\nFROM mcr.microsoft.com\/dotnet\/sdk:6.0-focal AS build\r\nWORKDIR \/src\r\nCOPY [\"MemoryLeakNET6.csproj\", \".\/\"]\r\nRUN dotnet restore \"MemoryLeakNET6.csproj\"\r\nCOPY . .\r\nWORKDIR \"\/src\/.\"\r\nRUN dotnet build \"MemoryLeakNET6.csproj\" -c Release -o \/app\/build\r\n\r\nFROM build AS publish\r\nRUN dotnet publish \"MemoryLeakNET6.csproj\" -c Release -o \/app\/publish \/p:UseAppHost=false\r\n\r\nFROM base AS final\r\nWORKDIR \/app\r\nCOPY --from=publish \/app\/publish .\r\nENTRYPOINT [\"dotnet\", \"MemoryLeakNET6.dll\"]<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
\u015eimdi ise dump alabilmek i\u00e7in container’\u0131n shell<\/i>\u00a0session’\u0131na girelim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
kubectl exec -it YOUR_POD_NAME -- \/bin\/sh<\/span><\/pre>\r\n<\/p>\r\n
<\/p>\r\n
Dump alma i\u015flemini linux<\/em> container i\u00e7erisinde ger\u00e7ekle\u015ftirebilmek i\u00e7in bir ka\u00e7 farkl\u0131 se\u00e7ene\u011fimiz bulunmakta. Ben bu sefer Microsoft<\/em>‘un .NET Core 3.1<\/em> ve \u00fczerine i\u00e7in sunmu\u015f oldu\u011fu .NET diagnostics CLI tools<\/em>‘unu kullanaca\u011f\u0131m. Bu tool’lar i\u00e7erisinde ise “dotnet-dump<\/em>” ve “dotnet-gcdump<\/em>” olmak \u00fczere iki farkl\u0131 tool bulunmakta. Ben dump analiz i\u015flemlerini ger\u00e7ekle\u015ftirirken SOS<\/em> komutlar\u0131ndan yararlanabilmek istedi\u011fim i\u00e7in, “dotnet-dump<\/em>” tool’unu kullanaca\u011f\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
\u00d6ncelikle a\u015fa\u011f\u0131daki komutlar\u0131 kullanarak, “dotnet-dump<\/em>” tool’unu container i\u00e7erisine indirelim. Farkl\u0131 platform se\u00e7eneklerine ise, buradan<\/a><\/em> eri\u015febilirsiniz.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
apt-get update\r\napt-get install wget\r\nwget -O dotnet-dump https:\/\/aka.ms\/dotnet-dump\/linux-x64\r\nchmod 777 .\/dotnet-dump<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
\u015eimdi dump almak istedi\u011fimiz uygulaman\u0131n process ID<\/em> bilgisine eri\u015febilmek i\u00e7in ise, “.\/dotnet-dump ps<\/em>” komutunu \u00e7al\u0131\u015ft\u0131ral\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Process ID<\/em> bilgisini elde ettikten sonra, a\u015fa\u011f\u0131daki komut ile uygulaman\u0131n dump’\u0131n\u0131 alal\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
.\/dotnet-dump collect -p YOUR_PROCESS_ID<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
G\u00f6rd\u00fc\u011f\u00fcm\u00fcz gibi “630MB<\/em>” lik bir full dump dosyas\u0131 olu\u015fturulmu\u015f durumda.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Local ortam\u0131m\u0131za kopyalamadan \u00f6nce ilgili dump dosyas\u0131n\u0131 ayn\u0131 \u015fekilde s\u0131k\u0131\u015ft\u0131rmam\u0131z gerekmektedir. Bu sefer ilgili container i\u00e7erisinde bulunan “gzip<\/em>” tool’undan yararlanabiliriz.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
gzip DUMP_NAME<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
Ard\u0131ndan “.gz<\/em>” uzant\u0131l\u0131 dump dosyas\u0131n\u0131, kendi local ortam\u0131m\u0131za a\u015fa\u011f\u0131daki gibi kopyalayabiliriz.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
kubectl cp YOUR_POD_NAME:\/app\/DUMP_NAME.gz .\/dotnetdump\/mydump.gz<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
WinDbg ile Dump Analizine Ba\u015flayal\u0131m<\/h2>\r\n
<\/p>\r\n
<\/p>\r\n
Dump dosyalar\u0131n\u0131 analiz edebilmek i\u00e7in WinDbg, <\/em>Visual Studio, PerfView<\/em>\u00a0<\/em>vb. gibi farkl\u0131 tool se\u00e7enekleri bulunmaktad\u0131r. Ben bu makale kapsam\u0131nda ise windows<\/em> container’dan alm\u0131\u015f oldu\u011fumuz dump i\u00e7in, WinDbg<\/em>‘\u0131 kullanaca\u011f\u0131m. E\u011fer daha g\u00f6rsel bir tool tercih etmek isterseniz ise di\u011fer se\u00e7enekleri de de\u011ferlendirebilirsiniz.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
WinDbg<\/em>‘a sahip de\u011filseniz buradaki<\/a> <\/em><\/strong>link \u00fczerinden “Debugging Tools for Windows<\/em>” ba\u015fl\u0131\u011f\u0131n\u0131 takip ederek elde edebilirsiniz. Ayr\u0131ca WinDbg Preview<\/em> ismi ile yeni bir versiyonu da bulunmakta. Fakat ben eski versiyonu gibi stable bir \u015fekilde \u00e7al\u0131\u015ft\u0131ramad\u0131m. Bu y\u00fczden preview olmayan versiyonu \u00fczerinden ilerleyece\u011fim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Dump alma i\u015flemini x86<\/em> hedef platform’u ile ger\u00e7ekle\u015ftirdi\u011fimiz i\u00e7in, WinDbg (x86)<\/em> versiyonunu \u00e7al\u0131\u015ft\u0131ral\u0131m ve “File>Open Crash Dump<\/em>” men\u00fcs\u00fcn\u00fc takip ederek “C:\\procdump<\/em>” dizini alt\u0131na kopyalam\u0131\u015f oldu\u011fumuz dump dosyas\u0131n\u0131 se\u00e7elim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
\u015eimdi ilk olarak debugging i\u015flemlerinde symbol’leri kullanabilmek i\u00e7in (callstack, variables<\/em>), a\u015fa\u011f\u0131daki gibi symbol search path’ine “Microsoft Symbol<\/em>” server ve uygulaman\u0131n pdb <\/i><\/strong>dosyalar\u0131n\u0131n bulundu\u011fu path’leri ekleyelim.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
.sympath srv*https:\/\/msdl.microsoft.com\/download\/symbols\r\n.sympath+ C:\\source\\MemoryLeakNETFramework\\bin\\Debug<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
Ard\u0131ndan detayl\u0131 symbol log’lar\u0131n\u0131 g\u00f6rebilmek ve yeni symbol bilgilerinin y\u00fcklenebilmesi i\u00e7in, a\u015fa\u011f\u0131daki iki komutu \u00e7al\u0131\u015ft\u0131ral\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
!sym noisy\r\n.reload<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
\u015eimdi ise managed code debug i\u015flemini ger\u00e7ekle\u015ftirebilmemiz i\u00e7in SOS Debugging Extension<\/em>‘\u0131n\u0131, WinDbg<\/em> i\u00e7erisine y\u00fcklememiz gerekmektedir. Bu y\u00fckleme i\u015flemi s\u0131ras\u0131nda ise y\u00fckleyecek oldu\u011fumuz SOS <\/i>extension’\u0131n\u0131n versiyonu ve bitness’\u0131, dump’\u0131n al\u0131nd\u0131\u011f\u0131 host \u00fczerindeki CLR<\/em> versiyonu ve bitness’\u0131 ile e\u015fle\u015fiyor olmas\u0131 gerekmektedir.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Neyseki “!analyze \u2013v<\/em>” komutu ile uygun olan SOS<\/em> extension kolay bir \u015fekilde y\u00fcklenebilmektedir. Normalde crash dump’lar\u0131 i\u00e7in exception analizlerinde kullanabilece\u011fimiz bu komut’u, gerekli olan t\u00fcm dll’lerin otomatik olarak symbol search path’leri \u00fczerinden y\u00fcklenebilmesi i\u00e7in de kullanabiliriz.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
\r\n
NOT<\/strong><\/em>: Uygun SOS<\/em> dll’inin bulunamamas\u0131 durumunda ise i\u015fler biraz karma\u015f\u0131kla\u015fmaktad\u0131r. E\u011fer dump’\u0131n al\u0131nd\u0131\u011f\u0131 hedef server’a hala eri\u015fim sa\u011flanabilyorsa, oradan ilgili SOS <\/em>ve mscordacwks<\/em> dll’lerinin al\u0131nmas\u0131 veya ilgili Microsoft<\/em> update patch’inin bulunup, ilgili patch i\u00e7ersinden ilgili dll’lerin al\u0131nmas\u0131 gerekmektedir. Ard\u0131ndan “.load C:\\SOS\\sos.XXX.dll<\/em>” komutu ile WinDbg<\/em> i\u00e7erisine manuel bir \u015fekilde dahil edilmelidir.<\/p>\r\n<\/blockquote>\r\n
<\/p>\r\n
<\/p>\r\n
\u015eimdi ilgili SOS<\/em> extension’\u0131n y\u00fcklenebilmesi i\u00e7in a\u015fa\u011f\u0131daki gibi “!analyze \u2013v<\/em>” komutunu \u00e7al\u0131\u015ft\u0131ral\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
G\u00f6rd\u00fc\u011f\u00fcm\u00fcz gibi SOS<\/em> extension’\u0131, “x86_4.8.4515.00<\/em>” versiyonu ile WinDbg<\/em> i\u00e7erisine load edilmi\u015f durumda. Ayr\u0131ca load edilmi\u015f olan di\u011fer extension’lar\u0131 da g\u00f6rebilmek i\u00e7in, “.chain<\/em>” komutunu \u00e7al\u0131\u015ft\u0131rmam\u0131z yeterli olacakt\u0131r.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Art\u0131k heap’i incelemeye ba\u015flayabiliriz. Bunun i\u00e7in ilk olarak a\u015fa\u011f\u0131daki komutu \u00e7al\u0131\u015ft\u0131ral\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
!dumpheap -stat<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
Bu komut bize k\u0131saca managed heap i\u00e7erisinde allocate edilmi\u015f objeleri ve onlar\u0131n ne kadar memory kulland\u0131klar\u0131n\u0131n istatistiksel bir \u00f6zetini g\u00f6stermektedir. Bizimde \u00f6rnek senaryo gere\u011fi amac\u0131m\u0131z memory leak’e sebebiyet veren noktay\u0131 belirleyebilmek oldu\u011fu i\u00e7in, heap \u00fczerinde neler olup bitti\u011fini incelemek bizi do\u011fru bir noktaya g\u00f6t\u00fcrecektir.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Yukar\u0131daki resme bakt\u0131\u011f\u0131m\u0131zda “MemoryLeakNETFramework.ProductDTO<\/em>” ve “System.Byte[]<\/em>” objelerinin “500000<\/em>” kere kay\u0131t edildi\u011fini ve ortalama “8MB<\/em>” ve “518MB<\/em>” yer kapl\u0131yor olduklar\u0131n\u0131 g\u00f6rebiliriz. Bu bilgilerden yola \u00e7\u0131karak memory leak olu\u015fumunun bu noktalardan kaynaklan\u0131yor olabilece\u011fini san\u0131r\u0131m s\u00f6yleyebiliriz. K\u0131sacas\u0131 memory leak kayna\u011f\u0131n\u0131n izini s\u00fcrerken objelerin ya \u00e7ok fazla kay\u0131t ediliyor olmas\u0131na yada kaplad\u0131klar\u0131 alanlar\u0131na g\u00f6re inceliyor olmam\u0131z gerekmektedir.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
\u015eimdi “MemoryLeakNETFramework.ProductDTO<\/em>” objesinin biraz daha detaylar\u0131na bakal\u0131m. Bunun i\u00e7in \u00f6ncelikle bu objenin method table’\u0131na eri\u015fmemiz gerekmektedir. Yani “MemoryLeakNETFramework.ProductDTO<\/em>” objesinin ilk s\u00fctun’unda bulunan MT<\/em> (Method Table) adresini kopyalayal\u0131m ve a\u015fa\u011f\u0131daki komutu \u00e7al\u0131\u015ft\u0131ral\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
!dumpheap -mt 010d4e80<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n
Ard\u0131ndan listelenen sonu\u00e7lar i\u00e7erisinden herhangi bir instance’\u0131n memory adresini alarak, a\u015fa\u011f\u0131daki gibi detaylar\u0131na eri\u015felim sa\u011flayal\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
!dumpobj 386fde58<\/pre>\r\n
<\/p>\r\n
<\/p>\r\n<\/a><\/figure>\r\n<\/div><\/p>\r\n
<\/p>\r\n
G\u00f6rd\u00fc\u011f\u00fcm\u00fcz gibi memory’deki objeleri dump ederek, dump’\u0131n\u0131 ald\u0131\u011f\u0131m\u0131z andaki de\u011ferlerine eri\u015febilmekteyiz.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
Dilersek “!objsize<\/em>” komutu ile, istedi\u011fimiz bir objenin size’\u0131n\u0131 da ayr\u0131ca g\u00f6rebiliriz. \u00d6rne\u011fin bu obje i\u00e7erisindeki “System.Byte[]<\/em>” field’\u0131n\u0131n size’\u0131n\u0131 g\u00f6rebilmek i\u00e7in, “Value<\/em>” s\u00fctun’unda bulunan referans adresini kopyalayal\u0131m ve a\u015fa\u011f\u0131daki komut’u \u00e7al\u0131\u015ft\u0131ral\u0131m.<\/p>\r\n
<\/p>\r\n
<\/p>\r\n
!objsize 386fde74<\/pre>\r\n
<\/p>\r\n
- .NET Core Uygulamalar\u0131n\u0131n Linux \u00dczerinde Debugging & Profiling \u0130\u015flemlerine Genel Bak\u0131\u015f \u2013 1 (Perf, LTTNg)<\/a><\/li>\r\n
![\"\"](\"\/wp-content\/uploads\/2022\/06\/top-pod.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/06\/download-expand-procdump.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/06\/get-dump-procdump.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/06\/compress-dump-procdump.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/06\/copy-dump-from-pod.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/07\/kubectl-top.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/07\/dotnet-get-dump.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/06\/windbg-load-first.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/06\/sos-loaded.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/07\/dump-heap.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/07\/dump-obj.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/07\/objsize.jpg\")
<\/a><\/figure>\r\n![\"\"](\"\/wp-content\/uploads\/2022\/07\/get-heap-core-dump.jpg\")
<\/a><\/figure>\r\n