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Have you encountered the following in your SQL Server error log?
Long Sync IO: Scheduler 95 had 1 Sync IOs in nonpreemptive mode longer than 1000 ms
There are two general types of I/O performed by SQL Server.
Async – Vast majority of SQL Server I/Os, as outlined in the provided link: https://technet.microsoft.com/en-us/library/aa175396(v=sql.80).aspx Sync
The message I am blogging on today is of the Sync variety. Simply stated the thread waits for the I/O to complete. For example:
Build message text for the SQL Server error log Call WriteFile – Until the I/O operation completes