All,

TASK_UNMAPPED_SIZE is defined in include/asm-i386/processor.h as:

#define TASK_UNMAPPED_SIZE    (TASK_SIZE / 3)

The value of TASK_SIZE is defined as PAGE_OFFSET which is set to 0xC0000000
(page.h).  This works out to be a value of 0x4000000.

The question is:
Are there any negative side effects in defining TASK_UNMAPPED_SIZE to 0x1000000?

By doing this we allow a process to access more memory.  On Oracle it allows us
to grow our buffer size from 1.7 GB to 2.4 GB improving overall performance by
reducing I/O.

Thanks in advance,

--
=======================================================================
  Josue Emmanuel Amaro                         Josue.Amaro@oracle.com
  Linux Products Manager                       Phone:   650.506.1239
  Intel and Linux Technologies Group           Fax:     650.413.0167
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