The Costs Of Rebuilding Indexes Online

Tibor Karaszi explains that TANSTAAFL (There A’int No Such Thing As A Free Lunch) applies to online index rebuilds:

The time it takes to rebuild the index can be substantially longer for ONLINE. Many of us has other things to do with the database during night-time and/or weekends. Yes, these are the typical window in time where we try to find things such as index rebuilds. Say that you do it night-time and it currently take 4 hours. Wouldn’t it be nice if you could cut that time down to 1.5 hours? That would leave more time for imports, massaging of data, CHECKDB and other things you want to do. Sure, you can do it ONLINE, but it will slow down access during the rebuild. Also the more data you modify during the rebuild, the more space you need in tempdb.

Betteridge’s Law of Headlines applies too, so that’s two important principles in one post.

As far as the post goes, Tibor makes a fair point: there is a trade-off between availability and efficiency with index rebuilds. But having worked with clustered columnstore indexes in 2014, you’ll pry the online operations in subsequent versions out of my cold, dead hands.

Related Posts

Defining Downtime Down

Andy Mallon takes us through the notion of downtime: There’s a lot of discussion about preventing downtime. As a DBA and IT professional, it’s my sworn duty to prevent downtime. I usually describe my job as DBA something along the lines of, “to make sure data is always available to the people and applications that […]

Read More

Trying Out the Data Migration Assistant

Dave Mason shares some thoughts on the Data Migration Assistant: I recently took advantage of an opportunity to try Mirosoft’s Data Migration Assistant. It was a good experience and I found the tool quite useful. As the documentation tells us, the DMA “helps you upgrade to a modern data platform by detecting compatibility issues that can impact database […]

Read More

Categories

January 2019
MTWTFSS
« Dec Feb »
 123456
78910111213
14151617181920
21222324252627
28293031