On Wed, Dec 18, 2013 at 5:51 PM, Bill Allombert <Bill.Allombert@math.u-bordeaux1.fr> wrote:
On Tue, Nov 13, 2012 at 04:03:01PM -0500, Igor Schein wrote:
> Package: pari
> Version: git-30598f4
>
> ?
> setrand(756);while(1,gettime;rnfkummer(bnrinit(bnfinit(quadpoly(13829,y)),211,1),[5,1;0,1]);print(gettime))
> 5516
> 6340
> 5873
> 5493
> 5432
> 5617
> 5588
> 15386
> 5652
> 5617
> 5429
> 5516
> 5465
> 5712
> 5685
> 5328
> ^C  ***   at top-level: ...and(756);while(1,gettime;rnfkummer(bnrinit(bn
>   ***                                             ^--------------------
>   *** rnfkummer: user interrupt after 1min, 40,690 ms.
>
> Nothing catastrophic by any means, but I was curious if there's a reason
> for the 8th iteration to be almost 3 times slower than the average - maybe
> there's a room for improvement somewhere.

I cannot reproduce this either now. But anyway, probabilistic algorithms are
expected to have unbounded running time.

Cheers,
Bill.

It's still hiding there, just need to pick the *right* seed to observe a 21x slowdown:

? setrand(Vecsmall([-8446149808577737181,8578936408666736270,1700487484344185372,-179919969120507962,-4569476776253702326,-2612446370896714550,-1404946945266012899,5685981555746785795,5625913321647327448,-3734337993207584891,-8197333092772190689,33608576481455252,-1496487397338386413,-6917614323314831553,2710916655870214852,920853737738877868,1432508769095704297,-899078375397171954,1984174560312052058,-7552114343640449022,3424517195330414512,1699397899807701904,-3075608205130206150,-4495693531543665194,-539619155765567094,-5239581636815839472,-8372227310394327268,8214605945228404731,2640404836820835466,-8501508634599399220,1204564931496642999,2486005181172373115,-948902143821956607,-6572729380344387727,-3657696290416385372,3717602477262699337,-8217363112475894551,-2816672702980700571,3419054888376672914,2381244515952014624,-5861400276409140535,2363142394724651455,1905073928909143972,-3097303017500105759,-5877089905990472524,-24594315368756238,3549820378252476858,7772304778500447350,-6080433654820611481,-4657693402839871862,2372604709228383114,3440698491637078600,3686780117792142992,512702924772965658,4416773783306663680,8133024360612993946,7712895979928808960,-6401532423647630545,1333395865579430181,-6386055020618503615,8358211330507622314,-730042652546701423,-2781157934151252133,-3066157610105361089,21,5519601660675621043]));bnfinit(x^36-18*x^30+423*x^24-1836*x^18+3807*x^12-1458*x^6+729;);
time = 1min, 9,379 ms.
? bnfinit(x^36-18*x^30+423*x^24-1836*x^18+3807*x^12-1458*x^6+729;);
time = 3,294 ms.

Igor