Memory consumption increases as requested ntoys increase

[afiqaize]

Hi,

This is a github issue version of [1]. The test command used to identify the issue is [2]. The setup used is [3], and the workspace file can be obtained in [4]. The memory pattern I got on a EL7 machine at DESY, changing only the argument to -t in [1], is [5].

Cheers,
Afiq

[1] https://cms-talk.web.cern.ch/t/understanding-the-memory-pattern-as-a-function-of-toys/16270

[2]

/usr/bin/time -f '%Uuser %Ssystem %Eelapsed %PCPU (%Xtext+%Ddata %Mmax)k' combineTool.py -v -1 -M MultiDimFit -d workspace_twin-g.root -m 400 -n _pnt_g1_0.0_g2_0.0_toys_0 --algo fixed --fixedPointPOIs 'g1=0.0,g2=0.0' --setParameters 'g1=0.0,g2=0.0'  --cminPreScan --cminDefaultMinimizerAlgo Migrad --cminDefaultMinimizerStrategy 0 --cminFallbackAlgo Minuit2,Simplex,0 -s -1 --toysFrequentist -t 10 --X-rtd MINIMIZER_analytic

[3] combine v8.2.0 in CMSSW_10_2_13, slc7_amd64_gcc700

[4] https://gitlab.cern.ch/cms-hcg/cadi/hig-22-013/-/blob/master/2D/A_m400_w4p0__H_m425_w2p0_lx/workspace_twin-g.root

[5]
ntoy max_memory
5 660860max
10 678128max
20 952588max
40 1348592max
80 2137032max
160 3637392max