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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
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#ifndef OS_AIX_GLOBALS_AIX_HPP
#define OS_AIX_GLOBALS_AIX_HPP

//
// Declare Aix specific flags. They are not available on other platforms.
//
// (Please keep the switches sorted alphabetically.)
#include "runtime/flags/jvmFlag.hpp"

    //  Whether to allow the VM to run if EXTSHM=ON. EXTSHM is an environment 
    //  variable used on AIX to activate certain hacks which allow more shm segments 
    //  for 32bit processes. For 64bit processes, it is pointless and may have 
    //  harmful side effects (e.g. for some reasonn prevents allocation of 64k pages 
    //  via shmctl). 
    //  Per default we quit with an error if that variable is found; for certain 
    //  customer scenarios, we may want to be able to run despite that variable. 
PRODUCT_FLAG(bool,     AllowExtshm, false, JVMFlag::DEFAULT,
                       "Allow VM to run with EXTSHM=ON.");


    //   Maximum expected size of the data segment. That correlates with the      
    //   to the maximum C Heap consumption we expect.                             
    //   We need to know this because we need to leave "breathing space" for the  
    //   data segment when placing the java heap. If that space is too small, we  
    //   reduce our chance of getting a low heap address (needed for compressed   
    //   Oops).                                                                   
PRODUCT_FLAG(uintx,    MaxExpectedDataSegmentSize, 8*G, JVMFlag::DEFAULT,
                       "Maximum expected Data Segment Size.");


    //  Use optimized addresses for the polling page.                             
PRODUCT_FLAG(bool,     OptimizePollingPageLocation, true, JVMFlag::DEFAULT,
                       "Optimize the location of the polling page used for Safepoints");


    //  Use 64K pages for virtual memory (shmat). 
PRODUCT_FLAG(bool,     Use64KPages, true, JVMFlag::DEFAULT,
                       "Use 64K pages if available.");


    //   If VM uses 64K paged memory (shmat) for virtual memory: threshold below  
    //   which virtual memory allocations are done with 4K memory (mmap). This is 
    //   mainly for test purposes.                                                
DEVELOP_FLAG(uintx,    Use64KPagesThreshold, 0, JVMFlag::DEFAULT,
                       "4K/64K page allocation threshold.");


    //  Normally AIX commits memory on touch, but sometimes it is helpful to have 
    //  explicit commit behaviour. This flag, if true, causes the VM to touch     
    //  memory on os::commit_memory() (which normally is a noop).                 
PRODUCT_FLAG(bool,     UseExplicitCommit, false, JVMFlag::DEFAULT,
                       "Explicit commit for virtual memory.");

//
// Define Aix-specific default values. The flags are available on all
// platforms, but they may have different default values on other platforms.
//

// UseLargePages means nothing, for now, on AIX.
// Use Use64KPages or Use16MPages instead.
define_pd_global(bool, UseLargePages, false);
define_pd_global(bool, UseLargePagesIndividualAllocation, false);
define_pd_global(bool, UseOSErrorReporting, false);
define_pd_global(bool, UseThreadPriorities, true) ;

#endif // OS_AIX_GLOBALS_AIX_HPP