locked
SQL Server 2014 wait info (HTDelete) RRS feed

  • Question

  • Hello,

    Recently we upgraded our one of the database from SQL Server 2012 to SQL Server 2014. In SQL Server 2014, I'm seeing the process which would run fine in SQL Server 2012 would be suspended with the wait_info (6305319ms)HTDELETE. There are no other process (or active spid) on this SQL Server 2014. I tried to lookup for more information on this HTDELETE, but could not find anything. The server is showing no activity i.e. no IO, CPU.

    sys.dm_exec_requests shows status Suspended and wait_type CXPACKET.

    I was wondering if anyone else has seen this wait_info or where to find more information?

    Thanks,

    Vijay

    Thursday, July 10, 2014 5:18 PM

Answers

  • Hello Everyone,

    I did get info from MS SQL Server support team on this, and might be beneficial if anyone else encounters this new wait type in SQL Server 2014:

    SQL Server 2014 now uses one shared hash table instead of per-thread copy.
    This provides the benefit of significantly lowering the amount of memory
    required to persist the hash table but, as you can imagine, the multiple
    threads depending on that single copy of the hash table must synchronize with
    each other before, for example, deallocating the hash table. To do so, those
    threads wait on the HTDELETE (Hash Table DELETE) wait type.<o:p></o:p>

    Thanks,

    Vijay

     
    • Marked as answer by VijayOhio Monday, July 28, 2014 6:53 PM
    Monday, July 28, 2014 6:53 PM