New thresholds in table

Niels Möller nisse at
Mon Nov 14 12:02:30 CET 2011

Torbjorn Granlund <tg at> writes:

> I suppose 10 is still too high then.  Or doesn't the code support lower
> values?

I think it should work with a threshold as low as 4 or so.

> The spreading of measured values for k10/k8 makes me suspect that
> something might not be right.
> All k10 and  k8 machines using 64-bit limbs get values less then 30,
> but one is far off that:
>          171
> These machines have two nehalem generation CPUs:
>   169
>          12

Hmm. I think the threshold should be in the same ballpark as
HGCD_THRESHOLD. Which makes small values for all x86_64, 64-bit ABI
builds suspicious. The smallest value for builds in that class is 78,

One would need to look at sime time/size graphs for those machines to
figure out what's right.

>From comments, it seems the reason min_size was set in tuneup for the
HGCD_THRESHOLD was some problem with bogus small results.

> Most of the GMP testing is nowadays done on emulators or under
> virtualisers; running tuneup there makes limited sense.

Then it would be good to somehow mark those which do make some sense, on
the threshold report pages...


Niels Möller. PGP-encrypted email is preferred. Keyid C0B98E26.
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