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RE: MAXACTION exceeded error while using systemtap


Frank Ch. Eigler wrote:
> Bug #1866 links to #1884, which does that.

Oops, sorry, I interpreted the "duplicate of" message backwards...

>> At the very least, we should have something along the Dtrace's
>> printa(): [...] Bug #1121 seems applicable to this problem [...]
> 
> The print/printf routines have worked for a few weeks now.  I don't
> know whether Graydon intends to extend them to print arrays also.

The bug mentions printing entire arrays - that is what I was referring
to.

> I am unsure about how to estimate the very real cost of an array-print
> operator.  Calling it approximately zero would make it into a
> something like a DoS vector.  Intuitively, it should be proportional
> to the amount of output generated, so it relates to bug #1885.

I guess it's a question of the purpose of MAXACTION.  My understanding
is that it is meant to avoid infinite loops/recursion.  In this sense,
giving printa a cost of one is ok, because the size of the array is
bound by MAXMAPENTRIES.

If you mean for MAXACTION to also provide a bound on time, then I tend
to agree with your comment #4 on 1884 - we need a way to determine a
more representative MAXACTION.


Josh


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