pageout_reserve
Parameter
- Description
-
Specifies the number of pages reserved for the exclusive use of the pageout or scheduler threads. When available memory is less than this value, nonblocking allocations are denied for any processes other than pageout or the scheduler. Pageout needs to have a small pool of memory for its use so it can allocate the data structures necessary to do the I/O for writing a page to its backing store.
- Data Type
-
Unsigned integer
- Default
-
throttlefree
/ 2 - Range
-
The minimum value is 64 KB or 1/512th of physical memory, whichever is greater, expressed as pages using the page size returned by
getpagesize(3C)
.The maximum is the number of physical memory pages. The maximum value should be no more than 2 percent of physical memory. The system does not enforce this range, other than that described in the Validation section.
- Units
-
Pages
- Dynamic?
-
Yes, unless dynamic reconfiguration operations that add or delete memory occur. At that point, the value is reset to the value provided in
/etc/system.d/file
or calculated from the new physical memory value. - Validation
-
If
pageout_reserve
is greater thanthrottlefree
/ 2,pageout_reserve
is set tothrottlefree
/ 2. No message is displayed. - Implicit
-
The relationship of
lotsfree
being greater thandesfree
, which is greater thanminfree
, 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 64 KB, expressed as pages using the page size returned by
getpagesize
. - Commitment Level
-
Unstable