Solaris Application Programming, 1/e - Chapter 4 - Parent Directory

54 Chapter 4 Informational Tools
$ pagesize -a
8192
65536
524288
4194304
Example 4.7 Sample Output from the pagesize Command
The pmap command (covered in Section 4.4.7) reports the page sizes that an
application has been allocated.
It is possible to change the page sizes that an application requests. You can do
this in several ways.
At compile time, you can use the -xpagesize compiler flag documented in
Section 5.8.6 of Chapter 5.
You can preload the Multiple PageSize Selection (mpss.so.1) library, which
uses environment variables to set the page sizes. We will cover preloading in
more detail in Section 7.2.10 of Chapter 7. An example of using preloading to
set the page size for an application appears in Example 4.8. In this example,
the environment is being set up to request 4MB pages for both the application
stack and the heap.
Example 4.8 Using mpss.so.1 to Set the Page Size for an Application
$ setenv MPSSHEAP 4M
$ setenv MPSSSTACK 4M
$ setenv LD_PRELOAD mpss.so.1
$ a.out
You can set the preferred page size for a command or for an already running
application through the ppgsz utility. This utility takes a set of page sizes
plus either a command to be run with those page sizes, or a pid for those
page sizes to be applied to. Example 4.9 shows examples of using the ppgsz
command.
% ppgsz -o heap=4M a.out
% ppgsz -o heap=64K -p
Example 4.9 Using the ppgsz Command
Table 4.1 shows the supported page sizes for various processors.