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Full Discussion: Perl: Need help comparing huge files
Top Forums Shell Programming and Scripting Perl: Need help comparing huge files Post 302671597 by Corona688 on Friday 13th of July 2012 05:26:04 PM
Old 07-13-2012
Perl's only limitation is the amount of memory in your system.

If these 205 million records are 4 or 5 bytes each like you've shown, that might amount to close to a gig of memory. If they're much larger, they probably won't fit into memory on a 32-bit system and other approaches would need to be tried, such as sorting them, so you can tell when a record's absent without having to load every possible record into memory at once...

If your records aren't as you've shown, then nothing we've written for you is likely to work at all anyway. We need to see what you're really dealing with.
 

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LEARN ABOUT HPUX

audit_memory_usage

audit_memory_usage(5)						File Formats Manual					     audit_memory_usage(5)

NAME

       audit_memory_usage - percentage of physical memory that can be used by audit subsystem

VALUES

   Failsafe
   Default
   Allowed values
   Recommended values
DESCRIPTION

       The  tunable  defines  the  percentage  of physical memory that can be used by audit records.  If the audit record memory usage exceeds the
       limit, the audit subsystem blocks the system call until memory usage comes down inside the limit.

   Who Is Expected to Change This Tunable?
       Administrator with proper privileges can change the value of

   Restrictions on Changing
       This tunable value can be changed any time, as this is a dynamic tunable; but its value can not be lowered below the memory currently  used
       by the audit subsystem for records.

   When Should the Value of This Tunable Be Raised?
       When the system to be audited is critical and generates many records.

   What are the Side Effects of Raising the Value?
       If  the	system is generating great number of records, and the value is raised, then it can create a lot of unflushed memory and might slow
       down the system.

   When Should the Value of This Tunable Be Lowered?
       When the audit subsystem is not generating many records.

   What are the Side Effects of Lowering the Value?
       If many audit records are generated, then the auditing subsystem might block the system call.

   What Other Tunable Values Should Be Changed at the Same Time?
       None.

WARNINGS

       All HP-UX kernel tunable parameters are release specific.  This parameter may be removed or have its meaning changed in future releases	of
       HP-UX.

       Installation  of  optional  kernel  software, from HP or other vendors, may cause changes to tunable parameter values.  After installation,
       some tunable parameters may no longer be at the default or recommended values.  For information about the effects of installation  on  tun-
       able  values,  consult  the documentation for the kernel software being installed.  For information about optional kernel software that was
       factory installed on your system, see at

AUTHOR

       was developed by HP.

SEE ALSO

       audit(5).

							     Tunable Kernel Parameters					     audit_memory_usage(5)
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