New and changed VMM tunables
VMM adds the following tunables to the system:
FILE_PAGES_MAX-
FILE_PAGES_MAX specifies the maximum capacity, in units
of PAGES, to cache file contents.
In very large memory systems (typically those with more
than 4GB of memory) the general purpose memory pool is
allowed to grow to a larger size than the file pages cache.
Should the general purpose memory pool exceed the
file page cache in size, then the excess of
general purpose memory can be utilized as process memory,
but not as file cache memory.
Increasing FILE_PAGES_MAX increases the system's capacity to
cache file pages, but decreases its ability to support general
purpose memory.
Conversely, decreasing FILE_PAGES_MAX decreases the file
memory which may be cached, but increases the general purpose
memory which can be supported.
For example, it is possible to support 64GB of general purpose memory
by setting FILE_PAGES_MAX to 262144
(supporting a file system cache of 1 gigabyte of memory).
KMA_POOL_MAX-
KMA_POOL_MAX
specifies the size (in bytes) of the per-CPU, per-allocation
size, memory pool to be retained by the kernel memory allocator.
A larger value of KMA_POOL_MAX will increase kernel performance, but
at the cost of increased kernel memory consumption.
VMM changes the default value of the following, existing tunable
parameter from 30 seconds to 10 seconds:
KMAGBTIME-
KMAGBTIME specifies how much time, in seconds, there is between successive attempts
by the kernel memory allocator to give back unused memory (for possible
use by processes or filesystems).
Increasing this value increases the kernel allocator's requirement for
memory.
Decreasing it increases the CPU usage of the giveback attempts.
Default, minimum, and maximum values for new and changed VMM tunables
Tunable
|
Default
|
Minimum
|
Maximum
|
KMA_POOL_MAX
|
Ox10000
|
0
|
Ox100000
|
FILE_PAGES_MAX
|
980000
|
32768
|
16777216
|
KMAGBTIME
|
10
|
5
|
2400
|
© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 22 April 2004