I think there was a link to an Aaron Bertrand post about MERGE issues. Do a web search for "sql server merge concurrency problem" and you will get a...

MERGE is buggy (still), still subject to race/concurrency issues and you should try it with triggers on the target table sometime ...

You can do this using the Import Data Wizard (SSMS Object Browser, right-click a Database, Tasks, Import Data...). From there you can save it off as an SSIS package...

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Try this at your own risk. I have used it in the past, but pretty sure it was for single-file/filegroup databases and they didn't have filestream.

drop table #files

drop table...

Not sure - I haven't had to install it for some time now.

So you aren't reading significant data, you have a config issue limiting memory usage or you aren't monitoring correctly in vSphere. Those are the only 3 options that I...

1) what is max memory setting in SQL Server?

2) SQL Server buffer pool will use all memory available to it up to the max mem setting. If queries are...

1) I think I would give the OS and other stuff more than 7GB of memory.

2) I would run a differential analysis of wait stats. capture them into a...

What size data is being accessed? If you have (or only access) small amounts of data then SQL Server will not acquire more memory than it needs.

Try dbcc memorystatus...

I'm not feeling very well (especially mentally) right now, but after upgrading to 2012 can't you do a new FULL backup and restore that to the secondary and start rolling...

Until you mentioned it I had never heard of Zabbix. That isn't a good sign for you BTW, as I have been dealing with SQL Server for ~20 years....

Please provide create table statements, insert statements and sample expected data so we can help you. Assuming you have a UNIQUE key for each row between the two systems...

You can get Tim Ford/Louis Davidson's free performance tuning with DMVs book. Glenn Berry's SQL Server Diagnostics Scripts. sp_whoisactive. Do your own file IO stall and wait...

Maybe retype the startup parameters completely? Perhaps some NULL character got in there that you can't see? Very odd scenario!