BobMgr::GetBuf: Sort Big Output Buffer write not complete after 60 seconds One of our production servers showing below error msg in Sql Server Log from last week, 


  SQL Server has encountered 20674 occurrence(s) of I/O requests taking longer than 15 seconds to complete on file [D:\Databasefile.mdf] in database [Database] (11). The OS file handle is 0x0000000000000828. The offset of the latest long I/O is: 0x00001c3bde0000
  and today in addition to the above one more msg, 
  
  BobMgr::GetBuf: Sort Big Output Buffer write not complete after 60 seconds.


is this the indication of a serious issue? How can we resolve this?
BobMgr::GetBuf: Sort Big Output Buffer write not complete after 60 seconds.


Big Output Buffers (BoBs) are used when a sort spills to tempdb.

The 'big' buffer optimizes for large sequential I/O instead of writing sort records individually.

A delay of this length indicates a problem with the disk subsystem.