Oracle Solaris Tunable Parameters Reference Manual



Specifies the minimum acceptable memory level. When memory drops below this number, the system biases allocations toward allocations necessary to successfully complete pageout operations or to swap processes completely out of memory. Either allocation denies or blocks other allocation requests.

Data Type

Unsigned integer


desfree / 2


The minimum value is 128 Kbytes or 1/256th of physical memory, whichever is greater, expressed as pages using the page size returned by getpagesize.

The maximum value is the number of physical memory pages. The maximum value should be no more than 7.5 percent of physical memory. The system does not enforce this range other than that described in the Validation section.




Yes, unless dynamic reconfiguration operations that add or delete memory occur. At that point, the value is reset to the value provided in the /etc/system file or calculated from the new physical memory value.


If minfree is greater than desfree, minfree is set to desfree / 2. No message is displayed.


The relationship of lotsfree being greater than desfree, which is greater than minfree, should be maintained at all times.

When to Change

The default value is generally adequate. For systems with relatively static workloads and large amounts of memory, lower this value. The minimum acceptable value is 128 Kbytes, expressed as pages using the page size returned by getpagesize.

Commitment Level