Protected Mode vs. Unreal Mode
Posted: Thu Nov 01, 2001 6:11 am
Dear Folks,
Hello. Does anyone have any opinions regarding whether protected mode or unreal mode faster? Clearly, less overhead is produced with unreal mode, but are there general speed improvements in using 32-bit code instead of 16-bit code with 32-bit addressing (the Intel optimization manuals seem to suggest 32-bit code is faster, but they may not be considering unreal mode)? Are there any reasons specific to SMP kernels to prefer protected mode? The kernel I am writing is dedicated to a specific application, so a general purpose protected mode application/kernel split does not seem particularly applicable (currently I am using unreal mode). Thank you very much for any information that you can provide on this subject and please have a nice day.
Sincerely,
[email protected]
Hello. Does anyone have any opinions regarding whether protected mode or unreal mode faster? Clearly, less overhead is produced with unreal mode, but are there general speed improvements in using 32-bit code instead of 16-bit code with 32-bit addressing (the Intel optimization manuals seem to suggest 32-bit code is faster, but they may not be considering unreal mode)? Are there any reasons specific to SMP kernels to prefer protected mode? The kernel I am writing is dedicated to a specific application, so a general purpose protected mode application/kernel split does not seem particularly applicable (currently I am using unreal mode). Thank you very much for any information that you can provide on this subject and please have a nice day.
Sincerely,
[email protected]