Create Table – Disk vs In-Memory Optimized

I had an interesting e-mail discussion related to the performance of create table.  The test being executed was a tight loop of create table statements.  The assumption put forth was in-memory optimized table creation was slower and they expected it to be faster.  We are not talking about the performance of inserts, updates, deletes and…


How It Works: Sync IOs in nonpreemptive mode longer than 1000 ms

  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:…


COLD, WARM, HOT … CLEAN, DIRTY, FREE … What Does All This Mean?

I was asked about these terms from a blog reader.  As I thought about these terms and how to blog about them I became concerned that I might just be as clear as mud, but I will do my best. Each of the terms means something within a specific context.   For example, when your teenager…


How It Works: Session/SPID (–2) for DTC Transactions

I have written on this subject before but it seems to come up from time to time, as it did again this week.  The Session (SPID) = –2 is just a place holder used by SQL Server to indicate that the DTC transaction is still active but there are no sessions enlisted/propagated into the transaction….