Re: [HACKERS] Self-modifying code

2005-12-16 Thread Alvaro Herrera
Tom Lane wrote:
> Alvaro Herrera <[EMAIL PROTECTED]> writes:
> > I just read an article on LWN.net about the usage of self-modifying code
> > for selecting the optimum code for a given operation at run time.
> 
> That went out with hula hoops, I think.  For sure the security
> implications of making your code segment writable mean that the bar for
> "is it worth it" is a WHOLE lot higher than "it might possibly make TAS
> a bit faster".

Actually I was thinking in the issue with defining different sets of TAS
for SMP versus non-SMP.  There was discussion that suggested handing off
two set of binaries, one for each configuration.  So it's not just "it
might possibly" but rather a possible answer to that problem, which was
not mentioned as minor and for which a solution was not found AFAIR.

However it's not something that I'll personally code, so I'll let
somebody else argue about it if they really care about the issue.  I
just felt the need to mention it.

-- 
Alvaro Herrerahttp://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support

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Re: [HACKERS] Self-modifying code

2005-12-14 Thread Tom Lane
Alvaro Herrera <[EMAIL PROTECTED]> writes:
> I just read an article on LWN.net about the usage of self-modifying code
> for selecting the optimum code for a given operation at run time.

That went out with hula hoops, I think.  For sure the security
implications of making your code segment writable mean that the bar for
"is it worth it" is a WHOLE lot higher than "it might possibly make TAS
a bit faster".

regards, tom lane

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