SQL Server Backup Buffers

SQLsasquatch (whose name I now know but I like the handle so much) has a few questions about backup buffers:

I wonder:
-If ‘max server memory’ wasn’t being overridden by a more reasonable target (because max server memory is 120 GB on a 32GB VM), would the behavior still be the same before reaching target?  I bet it would be.
-Is this behavior specific to not having reached target?  Or when reaching target would backup buffers be allocated, potentially triggering a shrink of the bpool, then returned to the OS afterward requiring the bpool to grow again?
-What other allocations are returned directly to the OS rather than given back to the memory manager to add to free memory?  I bet CLR does this, too.  Really large query plans?  Nah, I bet they go back into the memory manager’s free memory.
-Does this make a big deal?  I bet it could.  Especially if a system is prone to develop persistent foreign memory among its NUMA nodes.  In most cases, it probably wouldn’t matter.

Good questions, to which I have zero answers.

Related Posts

Creating Timelines With dbatools

Marcin Gminski shows how to pull SQL Agent and backup history out of SQL Server and display it as a visual history timeline: Currently, the output from the following commands is supported: Get-DbaAgentJobHistory Get-DbaBackupHistory You will run the above commands as you would normally do but pipe the output to ConvertTo-DbaTimeline, the same way as you […]

Read More

Finding The Last Database Restore Time

Lori Brown shows how you can see the last time a particular database was restored: I have a client that uses a lot of disconnected log shipping on a few servers.  They do this because they want to have a copy of their database that is actually hosted by software vendors for reporting purposes.  So, […]

Read More


June 2016
« May Jul »