Windows 재부팅 후 Postgresql이 특정 쿼리를 실패합니다.

Question

Windows에서 PostgreSQL을 C# 응용 프로그램으로 사용하고 있습니다. 내가 데 문제가 정말 이상한이며, 다음과 같이 설명 할 수 있습니다

• 나는 내 Windows는
• 내가 프로그램을 실행 다시 시작
은 하나 개의 특정 쿼리가 실패
• : SELECT COUNT(*) AS c FROM files WHERE total_bytes IS NOT NULL
• 다시 프로그램을 실행
  ,536,913 : 모든 것이 정상적으로

  이상한 노트 작동

• 그 전에 다른 쿼리를 만들려고했는데 같은 테이블을 사용해도 작동했습니다 : SELECT COUNT(*) AS c FROM files
• Postgresql을 다시 시작하는 동안 오류를 재현하지 못했습니다. Windows 재부팅시에만 발생합니다. 그리고 그것은 단지 한 번 발생합니다.

예외 추적 : 나는이 프로그램 작업을 계속해야하기 때문에

Npgsql.NpgsqlException: Exception while reading from stream 

    at Npgsql.ReadBuffer.Ensure(Int32 count, Boolean dontBreakOnTimeouts) 
    at Npgsql.NpgsqlConnector.DoReadMessage(DataRowLoadingMode dataRowLoadingMode, Boolean isPrependedMessage) 
    at Npgsql.NpgsqlConnector.ReadMessageWithPrepended(DataRowLoadingMode dataRowLoadingMode) 
    at Npgsql.NpgsqlConnector.ReadMessage(DataRowLoadingMode dataRowLoadingMode) 
    at Npgsql.NpgsqlConnector.ReadExpecting[T]() 
    at Npgsql.NpgsqlDataReader.NextResultInternal() 
    at Npgsql.NpgsqlDataReader.NextResult() 
    at Npgsql.NpgsqlCommand.Execute(CommandBehavior behavior) 
    at Npgsql.NpgsqlCommand.ExecuteDbDataReaderInternal(CommandBehavior behavior) 
    at Npgsql.NpgsqlCommand.ExecuteDbDataReader(CommandBehavior behavior) 
    at System.Data.Common.DbCommand.ExecuteReader() 
    at Npgsql.NpgsqlCommand.ExecuteReader() 
    at DriveShare.Database.Postgresql.ExecuteQuery(NpgsqlCommand command) in c:\projetos\driveshareclient\DriveShare\DriveShare\Database\Postgresql.cs:line 216 
    at DriveShare.Database.Postgresql.Query(String sql, Object[] args) in c:\projetos\driveshareclient\DriveShare\DriveShare\Database\Postgresql.cs:line 72 
    at DriveShare.Database.Postgresql.QueryOne(String sql, Object[] args) in c:\projetos\driveshareclient\DriveShare\DriveShare\Database\Postgresql.cs:line 83 
    at DriveShare.Database.Postgresql.QueryValue(String key, String sql, Object[] args) in c:\projetos\driveshareclient\DriveShare\DriveShare\Database\Postgresql.cs:line 97 
    at DriveShare.Database.Postgresql.QueryValue(String key, String sql) in c:\projetos\driveshareclient\DriveShare\DriveShare\Database\Postgresql.cs:line 92 
    at DriveShare.Database.FileIndexDataSet.CountIndexedFiles() in c:\projetos\driveshareclient\DriveShare\DriveShare\Database\FileIndexDataSet.cs:line 89 
    at DriveShare.Engine.DriveShareEngine.Start() in c:\projetos\driveshareclient\DriveShare\DriveShare\Engine\DriveShareEngine.cs:line 156 
    at DriveShareWebService.Program.Main(String[] args) in c:\projetos\driveshareclient\DriveShare\DriveShareWebService\Program.cs:line 19 

, 나는 응용 프로그램이 진행하기 전에 해당 쿼리를 다시 시도 할 해결 방법을 썼다. 나는 자랑 아니에요 : 나는 PostgreSQL을에 연결 (얇은 추상화 클래스) Npgsql을 사용하고

public void WaitForConnection() 
{ 
    int limitSeconds = 3 * 60; 
    var start = DateTime.Now; 
    while (true) 
    { 
     try 
     { 
      Log.WaitingForDatabaseConnection(); 
      Query("SELECT COUNT(*) AS c FROM files WHERE total_bytes IS NOT NULL"); 
      Log.DatabaseConnectionAquired(); 
      break; 
     } 
     catch (Exception e) 
     { 
      var wastedTime = DateTime.Now - start; 
      if (wastedTime.TotalSeconds > limitSeconds) 
       throw; 
      else 
       Log.Exception(e); 
     } 
     Thread.Sleep(1000); 
    } 
} 

.

2016-08-16 10:14:34 BRT LOG: database system was shut down at 2016-08-16 10:12:07 BRT 
2016-08-16 10:14:34 BRT FATAL: the database system is starting up 
2016-08-16 10:14:34 BRT LOG: MultiXact member wraparound protections are now enabled 
2016-08-16 10:14:34 BRT LOG: sistema de banco de dados está pronto para aceitar conexões 
2016-08-16 10:14:34 BRT LOG: autovacuum launcher started 
2016-08-16 10:17:16 BRT LOG: could not receive data from client: unrecognized winsock error 10053 
2016-08-16 10:17:27 BRT LOG: could not send data to client: unrecognized winsock error 10054 
2016-08-16 10:17:27 BRT STATEMENT: SELECT path FROM files 
2016-08-16 10:17:27 BRT FATAL: connection to client lost 
2016-08-16 10:17:27 BRT STATEMENT: SELECT path FROM files 
2016-08-16 10:17:27 BRT LOG: could not receive data from client: unrecognized winsock error 10053 
2016-08-16 10:17:27 BRT LOG: unexpected EOF on client connection with an open transaction 
2016-08-16 10:17:33 BRT LOG: unexpected EOF on client connection with an open transaction 
2016-08-16 10:25:14 BRT LOG: could not receive data from client: unrecognized winsock error 10053 
2016-08-16 10:25:15 BRT LOG: could not receive data from client: unrecognized winsock error 10053 
2016-08-16 10:25:15 BRT LOG: unexpected EOF on client connection with an open transaction 
2016-08-16 10:26:30 BRT LOG: could not send data to client: unrecognized winsock error 10054 
2016-08-16 10:26:30 BRT FATAL: connection to client lost 
2016-08-16 10:26:50 BRT LOG: could not send data to client: unrecognized winsock error 10054 
2016-08-16 10:26:50 BRT FATAL: connection to client lost 
2016-08-16 10:26:50 BRT LOG: could not receive data from client: unrecognized winsock error 10053 
2016-08-16 10:26:50 BRT LOG: unexpected EOF on client connection with an open transaction 
2016-08-16 10:27:06 BRT LOG: could not send data to client: unrecognized winsock error 10054 
2016-08-16 10:27:06 BRT FATAL: connection to client lost 
2016-08-16 10:27:06 BRT LOG: could not send data to client: unrecognized winsock error 10054 
2016-08-16 10:27:06 BRT FATAL: connection to client lost 
2016-08-16 10:27:30 BRT LOG: pedido de desligamento rápido foi recebido 
2016-08-16 10:27:30 BRT LOG: interrompendo quaisquer transações ativas 
2016-08-16 10:27:30 BRT LOG: autovacuum launcher shutting down 
2016-08-16 10:27:30 BRT ERROR: canceling statement due to user request 
2016-08-16 10:27:30 BRT LOG: autovacuum launcher shutting down 
2016-08-16 10:27:30 BRT LOG: shutting down 
2016-08-16 10:27:30 BRT LOG: database system is shut down 

나는 누군가가 내 문제가 정확히 무엇인지 알고 기대하지 않는다 : PostgreSQL을 로그는 아직 이해하지 못하는 윈속 오류에 대한 일부 항목을 보여줍니다. 나는 누군가가 그것에 빛을 비출 수있는 비슷한 문제를 가지고 있었으면 좋겠다.

Answer 1

Npgsql 문서에서 해결책을 찾았습니다. here.

기본적으로 Npgsql에는 연결 및 명령에 대한 일부 시간 초과 매개 변수가 있습니다. Windows 재부팅 후 테이블에 대한 첫 번째 액세스가 매우 느려 명령 제한 시간이 트리거되었습니다. 내가 실제 재부팅없이 문제를 재현하는 데 도움을 PostgreSQL의 기능 pg_sleep(seconds) :

connectionString += ";Timeout=180;Command Timeout=180"; 

보너스 팁 : 연결 문자열에 추가 매개 변수와

나는 더 높은 이러한 설정을 변경하고 내 문제를 해결할 수 있었다. 매우 도움이 됨 :

SELECT pg_sleep(60);