vps_ceiling
vps_ceiling specifies the maximum page size (in Kbytes)
that the kernel can select when it chooses a page size based on system
configuration and object size.
4
65536
16
Specify integer value. For more information, see Specifying Parameter Values.
This parameter is provided as a means to minimize lost cycle time caused by TLB (translation look-aside buffer) misses on systems using newer PA-RISC devices such as the PA-8000 that have smaller TLBs and no hardware TLB walker.
If a user application does not use the chatr command to
specify a page size for program text and data segments, the kernel
selects a page size that, based on system configuration and object size,
appears to be suitable. This is called transparent selection. The
selected size is then compared to the default maximum page-size value
defined by vps_ceiling that is configured at system-boot
time. If the the value is larger than vps_ceiling,
vps_ceiling is used.
The value is also compared with the default minimum page-size value
defined by
vps_pagesize that is configured at system-boot time.
If the the value is smaller than vps_pagesize,
vps_pagesize is used.
Note also that if the value specified by vps_ceiling is not
a legitimate page size, the kernel uses the next lower valid
value.
For more information about how these parameters are used and how they
affect system operation when user applications specify page sizes, refer
to the whitepaper document available as a PostScript file in
/usr/share/doc/var_pages.ps.