Memory-Optimized Table Warnings

Robert Davis looks at messages in the error log related to memory-optimized tables:

The server on which we are running in-memory OLTP is a really hefty server with 128 logical cores and 1.5 TB of RAM (1.4 TB allocated to SQL Server). We are limiting in-memory’s memory usage with Resource Governor, which also makes it easy to see how much it is using. Needless to say, even with a limited percentage of 1.4 TB of RAM is still a lot of memory. The highest I have seen in-memory usage for this one database reach at peak activity levels is ~43 GB. In production, when the heavy in-memory OLTP processes complete, I see the system reclaim the in-memory buffers pretty quickly, though not completely. During a normal day, I often see the in-memory memory usage hovering between 1 and 3 GB even when there is virtually no traffic.

When testing in-memory on a dev server that only I was using before deploying to production, I noticed that the memory usage would stay at whatever high level it reached. This makes me believe that in-memory buffers are cleaned up and reclaimed as needed, and if not needed, they just hang around as in-memory buffers. And it appears that some of the buffers end up hanging around. Perhaps they wouldn’t if the server was memory starved. I have not tested that theory.

It’s a conjecture, but seems pretty solid.  Also worth reiterating is that they’re warnings, not errors.

Related Posts

Causing Error 666 When Loading Into Columnstore Index

Joe Obbish has moved into Erik Darling’s Internet Basement and has a doozy of a first post there: I need to find a relatively efficient way to advance the CSILOCATOR because I need to do it over 2 billion times, if my theory is correct about the maximum allowed value. Both updating all of the […]

Read More

Trouble Installing CTP 2.5: msoledbsql.msi and msodbcsql.msi

Solomon Rutzky spent a lot of time troubleshooting a pernicious issue with SQL Server CTP 2.5 installation: The other day, I was <sarcasm>blessed / honored / delighted</sarcasm> to waste several hours attempting to install SQL Server 2019 CTP 2.5 over and over again. Each time it would get through the first several steps of the […]

Read More

Categories

January 2017
MTWTFSS
« Dec Feb »
 1
2345678
9101112131415
16171819202122
23242526272829
3031