Running: ./testmodel.py --libraries=/home/hudson/saved_omc/libraries/.openmodelica/libraries --ompython_omhome=/usr ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10.conf.json
loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo", uses=false)
loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo", uses=false)
loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+maint.om/package.mo", uses=false)
loadFile("/home/hudson/saved_omc/libraries/.openmodelica/libraries/ScalableTestSuite 2.2.0-master/package.mo", uses=false)
Using package ScalableTestSuite with version 2.2.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/ScalableTestSuite 2.2.0-master/package.mo)
Using package Modelica with version 4.0.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+maint.om/package.mo)
Using package Complex with version 4.0.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo)
Using package ModelicaServices with version 4.0.0 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo)
Running command: "" <> buildModelFMU(ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10,fileNamePrefix="ScalableTestSuite_ScalableTestSuite_Thermal_Advection_ScaledExperiments_SteamPipe_N_10",fmuType="me",version="2.0",platforms={"static"})
"" <> buildModelFMU(ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10,fileNamePrefix="ScalableTestSuite_ScalableTestSuite_Thermal_Advection_ScaledExperiments_SteamPipe_N_10",fmuType="me",version="2.0",platforms={"static"})
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo): time 0.001396/0.001397, allocations: 112.3 kB / 16.92 MB, free: 5.758 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo): time 0.001601/0.001601, allocations: 191.3 kB / 17.85 MB, free: 5.176 MB / 14.72 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+maint.om/package.mo): time 1.23/1.23, allocations: 222.9 MB / 241.5 MB, free: 15.28 MB / 206.1 MB
Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ScalableTestSuite 2.2.0-master/package.mo): time 0.8019/0.8019, allocations: 119.3 MB / 411 MB, free: 9.559 MB / 334.1 MB
Notification: Performance of FrontEnd - loaded program: time 0.0014/0.0014, allocations: 59.91 kB / 0.491 GB, free: 13.64 MB / 430.1 MB
Notification: Performance of FrontEnd - Absyn->SCode: time 0.4615/0.4629, allocations: 80.7 MB / 0.5699 GB, free: 43.39 MB / 462.3 MB
Notification: Performance of NFInst.instantiate(ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10): time 0.0139/0.4769, allocations: 12.57 MB / 0.5821 GB, free: 33.35 MB / 462.3 MB
Notification: Performance of NFInst.instExpressions: time 0.008089/0.485, allocations: 7.803 MB / 0.5898 GB, free: 27.08 MB / 462.3 MB
Notification: Performance of NFInst.updateImplicitVariability: time 9.354e-05/0.4852, allocations: 1.25 kB / 0.5898 GB, free: 27.08 MB / 462.3 MB
Notification: Performance of NFTyping.typeComponents: time 0.0002753/0.4855, allocations: 39.33 kB / 0.5898 GB, free: 27.05 MB / 462.3 MB
Notification: Performance of NFTyping.typeBindings: time 0.01003/0.4955, allocations: 3.24 MB / 0.593 GB, free: 24.82 MB / 462.3 MB
Notification: Performance of NFTyping.typeClassSections: time 0.0007482/0.4963, allocations: 207.1 kB / 0.5932 GB, free: 24.67 MB / 462.3 MB
Notification: Performance of NFFlatten.flatten: time 0.0005994/0.4969, allocations: 0.6094 MB / 0.5937 GB, free: 24.35 MB / 462.3 MB
Notification: Performance of NFFlatten.resolveConnections: time 8.75e-05/0.497, allocations: 32.39 kB / 0.5938 GB, free: 24.34 MB / 462.3 MB
Notification: Performance of NFEvalConstants.evaluate: time 0.0002027/0.4972, allocations: 190.6 kB / 0.594 GB, free: 24.27 MB / 462.3 MB
Notification: Performance of NFSimplifyModel.simplify: time 0.0003104/0.4975, allocations: 263 kB / 0.5942 GB, free: 24.12 MB / 462.3 MB
Notification: Performance of NFPackage.collectConstants: time 5.942e-05/0.4976, allocations: 20.69 kB / 0.5942 GB, free: 24.12 MB / 462.3 MB
Notification: Performance of NFFlatten.collectFunctions: time 0.01141/0.509, allocations: 5.867 MB / 0.6 GB, free: 18.76 MB / 462.3 MB
Notification: Performance of NFScalarize.scalarize: time 0.0001528/0.5092, allocations: 171.5 kB / 0.6001 GB, free: 18.59 MB / 462.3 MB
Notification: Performance of NFVerifyModel.verify: time 0.0003036/0.5096, allocations: 258.7 kB / 0.6004 GB, free: 18.34 MB / 462.3 MB
Notification: Performance of NFConvertDAE.convert: time 0.008127/0.5177, allocations: 3.606 MB / 0.6039 GB, free: 14.73 MB / 462.3 MB
Notification: Performance of FrontEnd - DAE generated: time 5.52e-06/0.5177, allocations: 0 / 0.6039 GB, free: 14.73 MB / 462.3 MB
Notification: Performance of FrontEnd: time 2.154e-06/0.5177, allocations: 0 / 0.6039 GB, free: 14.73 MB / 462.3 MB
Notification: Performance of Transformations before backend: time 8.496e-06/0.5178, allocations: 0 / 0.6039 GB, free: 14.73 MB / 462.3 MB
Notification: Model statistics after passing the front-end and creating the data structures used by the back-end:
 * Number of equations: 146
 * Number of variables: 146
Notification: Performance of Generate backend data structure: time 0.003903/0.5217, allocations: 1.42 MB / 0.6053 GB, free: 13.26 MB / 462.3 MB
Notification: Performance of prepare preOptimizeDAE: time 4.824e-05/0.5217, allocations: 11.89 kB / 0.6053 GB, free: 13.25 MB / 462.3 MB
Notification: Performance of preOpt introduceOutputAliases (simulation): time 9.642e-05/0.5218, allocations: 102.7 kB / 0.6054 GB, free: 13.14 MB / 462.3 MB
Notification: Performance of preOpt normalInlineFunction (simulation): time 0.0004389/0.5223, allocations: 96.31 kB / 0.6055 GB, free: 13.04 MB / 462.3 MB
Notification: Performance of preOpt evaluateParameters (simulation): time 0.0003708/0.5227, allocations: 347.5 kB / 0.6058 GB, free: 12.66 MB / 462.3 MB
Notification: Performance of preOpt simplifyIfEquations (simulation): time 3.482e-05/0.5227, allocations: 41.69 kB / 0.6059 GB, free: 12.62 MB / 462.3 MB
Notification: Performance of preOpt expandDerOperator (simulation): time 8.485e-05/0.5228, allocations: 72.02 kB / 0.6059 GB, free: 12.55 MB / 462.3 MB
Notification: Performance of preOpt clockPartitioning (simulation): time 0.001495/0.5243, allocations: 0.9432 MB / 0.6068 GB, free: 11.57 MB / 462.3 MB
Notification: Performance of preOpt findStateOrder (simulation): time 2.022e-05/0.5243, allocations: 7.938 kB / 0.6068 GB, free: 11.56 MB / 462.3 MB
Notification: Performance of preOpt replaceEdgeChange (simulation): time 5.022e-05/0.5244, allocations: 28 kB / 0.6069 GB, free: 11.54 MB / 462.3 MB
Notification: Performance of preOpt inlineArrayEqn (simulation): time 1.088e-05/0.5244, allocations: 19.98 kB / 0.6069 GB, free: 11.52 MB / 462.3 MB
Notification: Performance of preOpt removeEqualRHS (simulation): time 0.001449/0.5259, allocations: 0.8129 MB / 0.6077 GB, free: 10.7 MB / 462.3 MB
Notification: Performance of preOpt removeSimpleEquations (simulation): time 0.002331/0.5282, allocations: 2.35 MB / 0.61 GB, free: 8.258 MB / 462.3 MB
Notification: Performance of preOpt comSubExp (simulation): time 0.001384/0.5296, allocations: 0.897 MB / 0.6109 GB, free: 7.352 MB / 462.3 MB
Notification: Performance of preOpt resolveLoops (simulation): time 0.0004265/0.53, allocations: 382.6 kB / 0.6112 GB, free: 6.977 MB / 462.3 MB
Notification: Performance of preOpt evalFunc (simulation): time 0.06946/0.5995, allocations: 32 MB / 0.6425 GB, free: 3.16 MB / 494.3 MB
Notification: Performance of preOpt encapsulateWhenConditions (simulation): time 5.093e-05/0.5996, allocations: 51.2 kB / 0.6425 GB, free: 3.102 MB / 494.3 MB
Notification: Performance of pre-optimization done (n=72): time 3.767e-06/0.5996, allocations: 4 kB / 0.6425 GB, free: 3.098 MB / 494.3 MB
Notification: Performance of matching and sorting (n=102): time 0.02872/0.6283, allocations: 7.124 MB / 0.6495 GB, free: 11.92 MB / 0.4983 GB
Notification: Performance of inlineWhenForInitialization (initialization): time 4.916e-05/0.6284, allocations: 60.41 kB / 0.6495 GB, free: 11.85 MB / 0.4983 GB
Notification: Performance of selectInitializationVariablesDAE (initialization): time 0.0001967/0.6286, allocations: 179.9 kB / 0.6497 GB, free: 11.66 MB / 0.4983 GB
Notification: Performance of collectPreVariables (initialization): time 7.813e-05/0.6287, allocations: 41.7 kB / 0.6498 GB, free: 11.62 MB / 0.4983 GB
Notification: Performance of collectInitialEqns (initialization): time 0.0001075/0.6289, allocations: 181.1 kB / 0.6499 GB, free: 11.43 MB / 0.4983 GB
Notification: Performance of collectInitialBindings (initialization): time 0.000337/0.6292, allocations: 382.5 kB / 0.6503 GB, free: 11.05 MB / 0.4983 GB
Notification: Performance of simplifyInitialFunctions (initialization): time 0.0003015/0.6295, allocations: 202.9 kB / 0.6505 GB, free: 10.85 MB / 0.4983 GB
Notification: Performance of setup shared object (initialization): time 0.0001525/0.6297, allocations: 358.8 kB / 0.6508 GB, free: 10.49 MB / 0.4983 GB
Notification: Performance of preBalanceInitialSystem (initialization): time 0.0008248/0.6305, allocations: 0.4944 MB / 0.6513 GB, free: 9.996 MB / 0.4983 GB
Notification: Performance of partitionIndependentBlocks (initialization): time 0.0009182/0.6314, allocations: 0.6241 MB / 0.6519 GB, free: 9.34 MB / 0.4983 GB
Notification: Performance of analyzeInitialSystem (initialization): time 0.001868/0.6333, allocations: 1.196 MB / 0.6531 GB, free: 8.109 MB / 0.4983 GB
Notification: Performance of solveInitialSystemEqSystem (initialization): time 8.726e-06/0.6333, allocations: 4 kB / 0.6531 GB, free: 8.105 MB / 0.4983 GB
Notification: Performance of matching and sorting (n=132) (initialization): time 0.002505/0.6358, allocations: 1.52 MB / 0.6546 GB, free: 6.551 MB / 0.4983 GB
Notification: Performance of prepare postOptimizeDAE: time 2.445e-05/0.6359, allocations: 11.94 kB / 0.6546 GB, free: 6.539 MB / 0.4983 GB
Notification: Performance of postOpt simplifyComplexFunction (initialization): time 1.068e-05/0.6359, allocations: 0 / 0.6546 GB, free: 6.539 MB / 0.4983 GB
Notification: Performance of postOpt tearingSystem (initialization): time 0.00158/0.6375, allocations: 396.5 kB / 0.655 GB, free: 6.121 MB / 0.4983 GB
Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.0008615/0.6384, allocations: 223.7 kB / 0.6552 GB, free: 5.902 MB / 0.4983 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 0.003765/0.6421, allocations: 5.7 MB / 0.6607 GB, free: 15.95 MB / 0.5139 GB
Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.0005064/0.6427, allocations: 43.95 kB / 0.6608 GB, free: 15.9 MB / 0.5139 GB
Notification: Performance of postOpt collapseArrayExpressions (initialization): time 8.533e-05/0.6428, allocations: 40 kB / 0.6608 GB, free: 15.86 MB / 0.5139 GB
Notification: Model statistics after passing the back-end for initialization:
 * Number of independent subsystems: 11
 * Number of states: 0 ()
 * Number of discrete variables: 10 (state[10].phase,state[9].phase,state[8].phase,state[7].phase,state[6].phase,state[5].phase,state[4].phase,state[3].phase,state[2].phase,state[1].phase)
 * Number of discrete states: 0 ()
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for initialization (122):
 * Single equations (assignments): 112
 * Array equations: 0
 * Algorithm blocks: 0
 * Record equations: 0
 * When equations: 0
 * If-equations: 0
 * Equation systems (not torn): 0
 * Torn equation systems: 10
 * Mixed (continuous/discrete) equation systems: 0
Notification: Torn system details for strict tearing set:
 * Linear torn systems (#iteration vars, #inner vars, density): 0 systems
 * Non-linear torn systems (#iteration vars, #inner vars): 10 systems
   {(1,1), (1,1), (1,1), (1,1), (1,1), (1,1), (1,1), (1,1), (1,1), (1,1)}
Notification: Performance of prepare postOptimizeDAE: time 0.0004035/0.6432, allocations: 255.7 kB / 0.6611 GB, free: 15.61 MB / 0.5139 GB
Notification: Performance of postOpt lateInlineFunction (simulation): time 0.0001333/0.6433, allocations: 39.53 kB / 0.6611 GB, free: 15.57 MB / 0.5139 GB
Notification: Performance of postOpt wrapFunctionCalls (simulation): time 0.005182/0.6485, allocations: 4.205 MB / 0.6652 GB, free: 11.28 MB / 0.5139 GB
Notification: Performance of postOpt inlineArrayEqn (simulation): time 3.914e-05/0.6486, allocations: 39.94 kB / 0.6652 GB, free: 11.24 MB / 0.5139 GB
Notification: Performance of postOpt constantLinearSystem (simulation): time 9.578e-06/0.6486, allocations: 0 / 0.6652 GB, free: 11.24 MB / 0.5139 GB
Notification: Performance of postOpt simplifysemiLinear (simulation): time 1.396e-05/0.6486, allocations: 7.969 kB / 0.6653 GB, free: 11.23 MB / 0.5139 GB
Notification: Performance of postOpt removeSimpleEquations (simulation): time 0.001825/0.6504, allocations: 1.638 MB / 0.6669 GB, free: 9.543 MB / 0.5139 GB
Notification: Performance of postOpt simplifyComplexFunction (simulation): time 1.048e-05/0.6504, allocations: 0 / 0.6669 GB, free: 9.543 MB / 0.5139 GB
Notification: Performance of postOpt solveSimpleEquations (simulation): time 0.000661/0.6511, allocations: 167.8 kB / 0.667 GB, free: 9.379 MB / 0.5139 GB
Notification: Performance of postOpt tearingSystem (simulation): time 0.002347/0.6535, allocations: 0.6556 MB / 0.6677 GB, free: 8.691 MB / 0.5139 GB
Notification: Performance of postOpt inputDerivativesUsed (simulation): time 0.000103/0.6536, allocations: 47.88 kB / 0.6677 GB, free: 8.645 MB / 0.5139 GB
Notification: Performance of postOpt calculateStrongComponentJacobians (simulation): time 0.004062/0.6577, allocations: 6.063 MB / 0.6736 GB, free: 2.324 MB / 0.5139 GB
Notification: Performance of postOpt calculateStateSetsJacobians (simulation): time 6.763e-06/0.6577, allocations: 7.938 kB / 0.6736 GB, free: 2.316 MB / 0.5139 GB
Notification: Performance of postOpt symbolicJacobian (simulation): time 0.005285/0.663, allocations: 4.228 MB / 0.6778 GB, free: 13.99 MB / 0.5295 GB
Notification: Performance of postOpt removeConstants (simulation): time 0.0002019/0.6632, allocations: 175.7 kB / 0.6779 GB, free: 13.8 MB / 0.5295 GB
Notification: Performance of postOpt simplifyTimeIndepFuncCalls (simulation): time 0.0001161/0.6633, allocations: 31.98 kB / 0.678 GB, free: 13.77 MB / 0.5295 GB
Notification: Performance of postOpt simplifyAllExpressions (simulation): time 0.0004353/0.6638, allocations: 39.89 kB / 0.678 GB, free: 13.73 MB / 0.5295 GB
Notification: Performance of postOpt findZeroCrossings (simulation): time 0.0001829/0.664, allocations: 68.91 kB / 0.6781 GB, free: 13.66 MB / 0.5295 GB
Notification: Performance of postOpt collapseArrayExpressions (simulation): time 6.245e-05/0.664, allocations: 39.91 kB / 0.6781 GB, free: 13.62 MB / 0.5295 GB
Notification: Performance of sorting global known variables: time 0.0001076/0.6642, allocations: 125.5 kB / 0.6782 GB, free: 13.5 MB / 0.5295 GB
Notification: Performance of sort global known variables: time 1.2e-07/0.6642, allocations: 0 / 0.6782 GB, free: 13.5 MB / 0.5295 GB
Notification: Performance of remove unused functions: time 0.002849/0.667, allocations: 0.9918 MB / 0.6792 GB, free: 12.51 MB / 0.5295 GB
Notification: Model statistics after passing the back-end for simulation:
 * Number of independent subsystems: 1
 * Number of states: 20 (p[1],p[2],p[3],p[4],p[5],p[6],p[7],p[8],p[9],p[10],h[1],h[2],h[3],h[4],h[5],h[6],h[7],h[8],h[9],h[10])
 * Number of discrete variables: 20 ($cse1.phase,$cse1.region,$cse2.phase,$cse2.region,$cse3.phase,$cse3.region,$cse4.phase,$cse4.region,$cse5.phase,$cse5.region,$cse6.phase,$cse6.region,$cse7.phase,$cse7.region,$cse8.phase,$cse8.region,$cse9.phase,$cse9.region,$cse10.phase,$cse10.region)
 * Number of discrete states: 0 ()
 * Number of clocked states: 0 ()
 * Top-level inputs: 0
Notification: Strong component statistics for simulation (102):
 * Single equations (assignments): 82
 * Array equations: 0
 * Algorithm blocks: 0
 * Record equations: 10
 * When equations: 0
 * If-equations: 0
 * Equation systems (not torn): 0
 * Torn equation systems: 10
 * Mixed (continuous/discrete) equation systems: 0
Notification: Torn system details for strict tearing set:
 * Linear torn systems (#iteration vars, #inner vars, density): 0 systems
 * Non-linear torn systems (#iteration vars, #inner vars): 10 systems
   {(1,1), (1,1), (1,1), (1,1), (1,1), (1,1), (1,1), (1,1), (1,1), (1,1)}
Notification: Performance of Backend phase and start with SimCode phase: time 0.01022/0.6773, allocations: 5.668 MB / 0.6847 GB, free: 6.742 MB / 0.5295 GB
Notification: Performance of simCode: created initialization part: time 0.005196/0.6825, allocations: 2.543 MB / 0.6872 GB, free: 4.184 MB / 0.5295 GB
Notification: Performance of simCode: created event and clocks part: time 4.659e-06/0.6825, allocations: 0 / 0.6872 GB, free: 4.184 MB / 0.5295 GB
Notification: Performance of simCode: created simulation system equations: time 0.002362/0.6849, allocations: 1.475 MB / 0.6886 GB, free: 2.707 MB / 0.5295 GB
Notification: Performance of simCode: created of all other equations (e.g. parameter, nominal, assert, etc): time 0.001265/0.6862, allocations: 223.6 kB / 0.6889 GB, free: 2.488 MB / 0.5295 GB
Notification: Performance of simCode: created linear, non-linear and system jacobian parts: time 0.01461/0.7008, allocations: 9.797 MB / 0.6984 GB, free: 8.484 MB / 0.5452 GB
Notification: Performance of simCode: some other stuff during SimCode phase: time 0.0008749/0.7017, allocations: 1.098 MB / 0.6995 GB, free: 7.359 MB / 0.5452 GB
Notification: Performance of simCode: alias equations: time 0.00102/0.7028, allocations: 0.5079 MB / 0.7 GB, free: 6.848 MB / 0.5452 GB
Notification: Performance of simCode: all other stuff during SimCode phase: time 0.0005027/0.7033, allocations: 327.3 kB / 0.7003 GB, free: 6.527 MB / 0.5452 GB
Notification: Performance of SimCode: time 9.12e-07/0.7033, allocations: 0 / 0.7003 GB, free: 6.527 MB / 0.5452 GB
Notification: Performance of buildModelFMU: Generate the FMI files: time 0.9106/1.614, allocations: 51.37 MB / 0.7505 GB, free: 3.363 MB / 0.592 GB
Notification: Performance of buildModelFMU: Generate platform static: time 20.14/21.75, allocations: 3.938 kB / 0.7505 GB, free: 3.359 MB / 0.592 GB
(rm -f ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10.pipe ; mkfifo ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10.pipe ; head -c 1048576 < ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10.pipe >> ../files/ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10.sim & /home/hudson/saved_omc/OMSimulator/install/bin/OMSimulator -r=ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10_res.mat --tempDir=temp_ScalableTestSuite_ScalableTestSuite_Thermal_Advection_ScaledExperiments_SteamPipe_N_10_fmu --startTime=0 --stopTime=20 --timeout=300 --tolerance=1e-08 ScalableTestSuite_ScalableTestSuite_Thermal_Advection_ScaledExperiments_SteamPipe_N_10.fmu > ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10.pipe 2>&1)
diffSimulationResults("ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10_res.mat","/var/lib/jenkins1/ws/OpenModelicaLibraryTestingWork/OpenModelicaLibraryTesting/ReferenceFiles/ScalableTestSuite/ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10_res.mat","/var/lib/jenkins1/ws/OpenModelicaLibraryTestingWork/OpenModelicaLibraryTesting/files/ScalableTestSuite_ScalableTestSuite.Thermal.Advection.ScaledExperiments.SteamPipe_N_10.diff",relTol=0.003,relTolDiffMinMax=0.003,rangeDelta=0.001)
Reference file matches