Hello

Our site is in Azure with 14 GB of RAM and 100 DTU.
Site goes down for few minutes whenever there is high traffic .

We have tried a lot to identify issues, but so far we could not succeed.

From event log we could see below error, then after site goes down.

Application: Nop.Web.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.InvalidOperationException
   at System.Data.Entity.Core.Objects.ObjectStateManager.FixupKey(System.Data.Entity.Core.Objects.EntityEntry)
   at System.Data.Entity.Core.Objects.EntityEntry.AcceptChanges()
   at System.Data.Entity.Core.Objects.ObjectContext.AcceptAllChanges()
   at System.Data.Entity.Core.Objects.ObjectContext.SaveChangesToStore(System.Data.Entity.Core.Objects.SaveOptions, System.Data.Entity.Infrastructure.IDbExecutionStrategy, Boolean)

Exception Info: System.InvalidOperationException
   at System.Data.Entity.Core.Objects.ObjectContext.SaveChangesToStore(System.Data.Entity.Core.Objects.SaveOptions, System.Data.Entity.Infrastructure.IDbExecutionStrategy, Boolean)
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[[System.Int32, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]](System.Func`1<Int32>)
   at System.Data.Entity.Core.Objects.ObjectContext.SaveChangesInternal(System.Data.Entity.Core.Objects.SaveOptions, Boolean)
   at System.Data.Entity.Internal.InternalContext.SaveChanges()
   at Nop.Data.EfRepository`1[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].Insert(System.__Canon)
   at Nop.Services.Logging.DefaultLogger.InsertLog(Nop.Core.Domain.Logging.LogLevel, System.String, System.String, Nop.Core.Domain.Customers.Customer)
   at Nop.Services.Logging.LoggingExtensions.FilteredLog(Nop.Services.Logging.ILogger, Nop.Core.Domain.Logging.LogLevel, System.String, System.Exception, Nop.Core.Domain.Customers.Customer)
   at Nop.Services.Logging.LoggingExtensions.Error(Nop.Services.Logging.ILogger, System.String, System.Exception, Nop.Core.Domain.Customers.Customer)
   at Nop.Services.Tasks.TaskThread.Run()
   at Nop.Services.Tasks.TaskThread.TimerHandler(System.Object)
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.TimerQueueTimer.CallCallback()
   at System.Threading.TimerQueueTimer.Fire()
   at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
   at System.Threading.ThreadPoolWorkQueue.Dispatch()


If any one has got the same issues. then please help me to resolve this issues