SharePoint 2016: Drives are at risk of running out of free space

Problem

Performing routine check on system health, you discover the following warning in the farm's Health Reports:

Title	Drives are at risk of running out of free space.
Severity	2 - Warning
Category	Availability
Explanation	Available drive space is less than five times the value of physical memory. This is dangerous because it does not provide enough room for a full memory dump with continued operation. It also could cause problems with the Virtual Memory swap file: [failing drives]
Remedy	Examine the failing servers and delete old logs or free space on the drives. For more information about this rule, see http://go.microsoft.com/fwlink/?LinkID=142688
Failing Servers	[a farm WFE]
Failing Services	SPTimerService (SPTimerV4)
Rule Settings	View

You check system drive and find that available space is 5 x greater than configured RAM.  rrr

Solution

• This rule checks for drive space exceeding 5 x configured system memory.  It executes as all or nothing, meaning that all server drives must meet the 5 x threshold and if any one is deficient then the warning is triggered.  You can of course disable the rule.  However, another approach available to you if your farm servers are virtualized is to go ahead and configure the failing drive or drives as managed with increased disk space: while SharePoint sees a larger drive, the hypervisor only allocates necessary drive space.  Thus there is no actual increase in resource usage.

References

• TechNet SharePoint 2016
• Drives are at risk of running out of free space (SharePoint Server 2016)
• TechNet SharePoint Forums
• Drives are at risk of running out of free space.
• Disks running out of space according to SharePoint 2010