>> The following program prints:
>>
>> Average msecs per MB 4.914158; Average copy rate: 0.000005 msecs/byte
>>
>> if run without root permission (i.e. mlockall() fails), and
>>
>> Average msecs per MB 7.417227; Average copy rate: 0.000007 msecs/byte
>>
>> if run with root permission.
>>
>> Is there a simple explanation ?
>
>mlockall() is a privileged call. Performance could improve if all pages
>are locked. The non-root version doesn't perform as well because
>mlockall() fails, subjecting the pages to the system's evil memory
>management schemes (paging/etc).
>
>I'm almost positive you know this though, so your question seems strange.
Look at what I wrote again. It runs *slower* when run as root, and
faster when not. That is, mlockall() causes it run slower.
--p
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This archive was generated by hypermail 2b29 : Fri Apr 07 2000 - 21:00:10 EST