I tried to replace all Joiners, and I also forced these group of workspace to use only 1 specific engine.I still have workspaces using both joiner, reader, sqlexecutors - however now they do not seem to fail.I suspect there is an issue when 2 different Engines runs simultaneously connecting to the same MS SQL-database.

Well, case solved for now, and I`ll repost in this thread if the issue starts again.Thanks for all the reply - and the reason I put it here on the forum is for people to easily try the different solutions here if they experience issues with MS SQL on FME Server.

We are fairly sure now that this was a known issue with the Joiner which was reported and fixed in FME 2016.1.2 Build 16670 (PR#71929).The issue is known to have caused workspaces to fail intermittently on FME Server when the Joiner was connecting to Microsoft SQL Server or Oracle and possibly other databases.We will create a Knowledge Center article shortly and include the link here.Upgrading FME Desktop and FME Server to 2016.1.2 or later and upgrading any Joiner transformers within the workspace should hopefully resolve this issue.

Is there any chance the link between FME Server and the Database system drops at all?Even for a split second?I'm really curious to learn more about this.You have experienced several variations of the SQL Server provider error.
Can you confirm that the FME Server system only has the SQL Server 2012 client installed and the 2008 client was removed?

In the fmeServerConfig.txt there is a part:

#-------------------------------------- # Limits #-------------------------------------- MAX_TRANSACTION_RESULT_SUCCESSES=100 MAX_TRANSACTION_RESULT_FAILURES=10 MAX_FAILED_TRANSACTION_REQUEST_RETRIES=3 MAX_REGISTRATION_READ_ATTEMPTS=6000 REGISTRATION_READ_RETRY_WAIT=10 MAINTENANCE_IDLE_WAIT=90000 TRANSACTION_DB_RETRY_WAIT=20

1。它这不仅关系到FME引擎和核心之间的通信 - 或者它也适用于任何其他databaseconnections？

2。有没有定义从FME引擎databaseconnections的最大数量的参数？Some simple math if a assume one FME Workspace that contains 10 reader/joiner/sqlexecutor with the same database connection uses 10 database-connections (1 connection per transformer) and they run 10 workspaces on 10 minutes.Then the number of database-connections to the same database by FME is 10 connections/workspace * 10 workspaces run = 100 connections per 10 minutes.

3。难道一个FME工作区手柄1数据库连接为一个单一的连接，或多个连接在几个SQLExecutors，加入者，读者，作者使用的是什么时候？If FME handles one Database Connection as 1 connection through the whole run of the workspace (regardles if there is a Joiner, SQLExecutor, Reader, Writer) that uses the same connection - then the needed connections is only 10.

It seems the issue is due to the process taking to long to process - expiring the timeout for keeping the database connection.even though it was set on 10 minutes on all joiner, reader, sqlexecutor.The trick was to optimize the workspace and replace sqlexecutors with joiners (with Prefetch-queries).We only worked with 8000 rows in this case, however it really slowed down due to very non-optimal workspace.For instance sending 8000 sqls one and one to a server, and doing this multiple times resulted in runtime of more than 10 minutes.With optimizations it seems to work great and spend less than 1minute in the same data.

Perhaps write an error in the log when "Database connection from Joiner_4 / FeatureReader_2 / SQLExecutor_2 have timed out (timeout set to 600) - optimize query or set a larger timeout) - so you can easily see in the logfile - and find the correct Transformer among many

No luck :(

However now when some workspace fails, it is in 90% of the cases 2 of the particular workspaces.I suspect that there are just too many joiners / sqlexecutors / readers either in one workspace or that the connection after them does not get cleaned up properly after each run.Unfortunately it is difficult for me to get access to the admin of the database to see the connections.I will try that today and keep this thread update for anyone else with similar issue.

我看见我只有在服务器安装本地客户端2008 - 从已安装的64位本机客户端2012（https://www.microsoft.com/en-us/download/details.aspx?id=29065）

注：下载链接的指示下找到点击下载时，不要。

将重新启动，看看是否有任何变化。