并发请求太多，服务器崩溃了？试试使用 ASP.NET Core Web API 操作筛选器对请求进行限流

using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Filters;
using Microsoft.Extensions.Caching.Memory;
public class RateLimitFilter : IAsyncActionFilter
{
  private readonly IMemoryCache memCache;
  // 注入的IMemoryCache
  public RateLimitFilter(IMemoryCache memCache)
  {
    this.memCache = memCache;
  }
  public Task OnActionExecutionAsync(
    ActionExecutingContext context, 
    ActionExecutionDelegate next)
  {
    // 通过注入的 IMemoryCache 来记录用户上一次访问的时间戳
    // 在分布式系统下可以改用分布式缓存来代替内存缓存
    string removeIP = context.HttpContext.Connection.RemoteIpAddress!.ToString();
    string cacheKey = $"LastVisitTick_{removeIP}";
    
    // 从缓存中获取这个客户端IP地址上一次访问服务器的时间
    long? lastTick = memCache.Get<long?>(cacheKey);
    if (lastTick == null || Environment.TickCount64 - lastTick > 1000)
    {
      // 如果缓存中不存在上一次访问时间或者上一次访问时间距离现在已经超过 1s，则通过 next 来执行后面的筛选器
      memCache.Set(cacheKey, Environment.TickCount64, TimeSpan.FromSeconds(10));
      return next();
    }
    else
    {
      // 否则说明 IP 频繁访问，不执行 next，相当于终止操作方法的执行
      context.Result = new ContentResult { StatusCode = 429 };
      return Task.CompletedTask;
    }
  }
}

using Microsoft.AspNetCore.Mvc;
var builder = WebApplication.CreateBuilder(args);
// Add services to the container.
builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
// 注册内存缓存服务
builder.Services.AddMemoryCache();
// 注册请求限流过滤器
builder.Services.Configure<MvcOptions>(options => { 
  options.Filters.Add<RateLimitFilter>();
});
var app = builder.Build();
// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
  app.UseSwagger();
  app.UseSwaggerUI();
}
app.UseHttpsRedirection();
app.UseAuthorization();
app.MapControllers();
app.Run();