问题描述

如果使用Azure App Service部署.NET 应用，会发现在内容并没有达到100%的时候，也会出现OOM错误。这是一个什么情况呢？

image.png

大内存测试代码

   static void Main(string[] args)
        {
            Console.WriteLine("Hello, World!"); int objunmbers = 20000; byte[][] largeArray = new byte[objunmbers][];

            Console.WriteLine("Start to create big memory object ... from 2GB"); //Console.WriteLine("Start to create big memory object ... from 20MB");
            long size = 2L * 1024 * 1024 * 1024; // 2GB //long size = 2L * 1024 * 1024 * 10; // 20MB
            int times = 1; while (size > 0)
            { if (CreateBigMemoryObject(largeArray,size, times))
                {
                    Console.WriteLine($"[{times}] Successfully created memory object of size: {size} bytes ({size / 1024 / 1024} MB)");

                    times = times + 1;
                } else {
                    Console.WriteLine($"Failed to create memory object of size: {size} bytes ({size / 1024 / 1024} MB). Trying smaller size...");
                    size = size - 100 * 1024 * 1024; // Decrease by 100MB //size = size - 1 * 1024 * 1024; // Decrease by 1MB
 } //Thread.Sleep(2000);
 }

            Console.WriteLine("Finished memory allocation attempts.");
            Console.WriteLine("sleep 5 mins");
            Thread.Sleep(5 * 60 * 1000);
            Console.WriteLine("End");
        } static bool CreateBigMemoryObject(byte[][] largeArray,long size,int index)
        { try {
                largeArray[index] = new byte[size]; return true;
            } catch (OutOfMemoryException ex)
            {
                Console.WriteLine($"OutOfMemoryException: {ex.Message}");
            } catch (Exception ex)
            {
                Console.WriteLine($"Exception: {ex.Message}");
            } return false;
        }