Fiasco vs Hazelnut

Gernot Heiser gernot at
Fri Mar 14 14:05:52 CET 2003

>>>>> On 14 Mar 2003 10:26:00 +0100, Jacob Gorm Hansen <jg at> said:
JGH> On Fri, 2003-03-14 at 01:58, Cristiano Ligieri Pereira wrote:
>> I certainly looked through the FAQs first before posting this question but
>> did not find any clean distinction between both kernel versions. I was
>> already told and could check myself that there are performance
>> differences. Are these differences described anywhere in the website and I
>> missed it?
>> What are the major differences between these two? 

>> From a user perspective I think these are the main points:

JGH> - Fiasco supports 64 bit thread ids, aka 2047 rather than 255 maximum
JGH> tasks.
JGH> - Fiasco implements a little more security, especially in relation to
JGH> task ownership.

Is "a little more security" similar to "a little bit pregnant"?

I don't think either has a real security model implemented. Most of
the V2 kernels (x86, Alpha, MIPS) have it, but none of the later ones

Gernot Heiser                        School of Computer Sci. & Engin.
Professor of Operating Systems       The University of NSW
Phone: +61 2 9385 5156               UNSW SYDNEY NSW 2052, Australia
Fax:   +61 2 9385 7348     

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