Running: ./testmodel.py --libraries=/home/hudson/saved_omc/libraries/.openmodelica/libraries --ompython_omhome=/usr Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified.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/Buildings 10.1.1-maint.10.0.x/package.mo", uses=false) Using package Buildings with version 10.1.1 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Buildings 10.1.1-maint.10.0.x/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: translateModel(Buildings.Fluid.Movers.Validation.PowerSimplified,tolerance=1e-06,outputFormat="mat",numberOfIntervals=5000,variableFilter="time|pump_y.P|pump_dp.P|pump_m_flow.P|pump_y.per.speed_nominal|y.y",fileNamePrefix="Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified") translateModel(Buildings.Fluid.Movers.Validation.PowerSimplified,tolerance=1e-06,outputFormat="mat",numberOfIntervals=5000,variableFilter="time|pump_y.P|pump_dp.P|pump_m_flow.P|pump_y.per.speed_nominal|y.y",fileNamePrefix="Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified") Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo): time 0.004934/0.004934, allocations: 102.2 kB / 15.73 MB, free: 6.449 MB / 14.72 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo): time 0.001096/0.001096, allocations: 199.1 kB / 16.68 MB, free: 6.352 MB / 14.72 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+maint.om/package.mo): time 1.383/1.383, allocations: 222.9 MB / 240.4 MB, free: 4.289 MB / 190.1 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Buildings 10.1.1-maint.10.0.x/package.mo): time 2.676/2.676, allocations: 437 MB / 0.7105 GB, free: 4.996 MB / 0.5606 GB Notification: Performance of FrontEnd - loaded program: time 0.00133/0.00133, allocations: 71.89 kB / 1.019 GB, free: 14.54 MB / 0.7794 GB Notification: Performance of FrontEnd - Absyn->SCode: time 0.35/0.3513, allocations: 151.6 MB / 1.167 GB, free: 6.801 MB / 0.92 GB Notification: Performance of NFInst.instantiate(Buildings.Fluid.Movers.Validation.PowerSimplified): time 0.08299/0.4344, allocations: 75.98 MB / 1.241 GB, free: 10.55 MB / 0.9981 GB Notification: Performance of NFInst.instExpressions: time 0.7647/1.199, allocations: 26.12 MB / 1.266 GB, free: 5.539 MB / 0.9981 GB Notification: Performance of NFInst.updateImplicitVariability: time 0.006626/1.206, allocations: 126.2 kB / 1.266 GB, free: 5.539 MB / 0.9981 GB Notification: Performance of NFTyping.typeComponents: time 0.009984/1.216, allocations: 2.642 MB / 1.269 GB, free: 5.484 MB / 0.9981 GB Notification: Performance of NFTyping.typeBindings: time 0.01334/1.229, allocations: 4.327 MB / 1.273 GB, free: 5.309 MB / 0.9981 GB Notification: Performance of NFTyping.typeClassSections: time 0.009703/1.239, allocations: 3.368 MB / 1.277 GB, free: 5.238 MB / 0.9981 GB Notification: Performance of NFFlatten.flatten: time 0.04691/1.286, allocations: 27.44 MB / 1.303 GB, free: 1.676 MB / 0.9981 GB Notification: Performance of NFFlatten.resolveConnections: time 0.006826/1.293, allocations: 3.038 MB / 1.306 GB, free: 312 kB / 0.9981 GB Notification: Performance of NFEvalConstants.evaluate: time 0.01085/1.304, allocations: 3.352 MB / 1.31 GB, free: 14.96 MB / 1.014 GB Notification: Performance of NFSimplifyModel.simplify: time 0.007236/1.311, allocations: 2.695 MB / 1.312 GB, free: 13.9 MB / 1.014 GB Notification: Performance of NFPackage.collectConstants: time 0.002108/1.313, allocations: 355.4 kB / 1.313 GB, free: 13.9 MB / 1.014 GB Notification: Performance of NFFlatten.collectFunctions: time 0.009487/1.322, allocations: 2.525 MB / 1.315 GB, free: 13.2 MB / 1.014 GB Notification: Performance of NFScalarize.scalarize: time 0.002977/1.325, allocations: 1.712 MB / 1.317 GB, free: 12.52 MB / 1.014 GB Notification: Performance of NFVerifyModel.verify: time 0.007732/1.333, allocations: 2.614 MB / 1.319 GB, free: 10.88 MB / 1.014 GB Notification: Performance of NFConvertDAE.convert: time 0.01779/1.351, allocations: 7.825 MB / 1.327 GB, free: 6.855 MB / 1.014 GB Notification: Performance of FrontEnd - DAE generated: time 5.611e-06/1.351, allocations: 0 / 1.327 GB, free: 6.855 MB / 1.014 GB Notification: Performance of FrontEnd: time 2.314e-06/1.351, allocations: 6.75 kB / 1.327 GB, free: 6.852 MB / 1.014 GB Notification: Performance of Transformations before backend: time 0.0003144/1.351, allocations: 0 / 1.327 GB, free: 6.852 MB / 1.014 GB Notification: Model statistics after passing the front-end and creating the data structures used by the back-end: * Number of equations: 450 * Number of variables: 450 Notification: Performance of Generate backend data structure: time 0.01728/1.369, allocations: 5.883 MB / 1.333 GB, free: 2.59 MB / 1.014 GB Notification: Performance of prepare preOptimizeDAE: time 4.688e-05/1.369, allocations: 16.61 kB / 1.333 GB, free: 2.582 MB / 1.014 GB Notification: Performance of preOpt normalInlineFunction (simulation): time 0.009849/1.379, allocations: 1.318 MB / 1.334 GB, free: 1.957 MB / 1.014 GB Notification: Performance of preOpt evaluateParameters (simulation): time 0.01406/1.393, allocations: 5.986 MB / 1.34 GB, free: 14.09 MB / 1.029 GB Notification: Performance of preOpt simplifyIfEquations (simulation): time 0.000203/1.393, allocations: 149.8 kB / 1.34 GB, free: 14.02 MB / 1.029 GB Notification: Performance of preOpt expandDerOperator (simulation): time 0.0008309/1.394, allocations: 201.2 kB / 1.34 GB, free: 13.96 MB / 1.029 GB Notification: Performance of preOpt clockPartitioning (simulation): time 0.006752/1.4, allocations: 2.491 MB / 1.343 GB, free: 12.45 MB / 1.029 GB Notification: Performance of preOpt findStateOrder (simulation): time 6.942e-05/1.401, allocations: 7.891 kB / 1.343 GB, free: 12.44 MB / 1.029 GB Notification: Performance of preOpt replaceEdgeChange (simulation): time 0.0003676/1.401, allocations: 79.5 kB / 1.343 GB, free: 12.38 MB / 1.029 GB Notification: Performance of preOpt inlineArrayEqn (simulation): time 6.027e-05/1.401, allocations: 49.38 kB / 1.343 GB, free: 12.38 MB / 1.029 GB Notification: Performance of preOpt removeEqualRHS (simulation): time 0.005535/1.407, allocations: 1.975 MB / 1.345 GB, free: 11.43 MB / 1.029 GB Warning: The model contains alias variables with redundant start and/or conflicting nominal values. It is recommended to resolve the conflicts, because otherwise the system could be hard to solve. To print the conflicting alias sets and the chosen candidates please use -d=aliasConflicts. Notification: Performance of preOpt removeSimpleEquations (simulation): time 0.02046/1.427, allocations: 11.17 MB / 1.355 GB, free: 1.637 MB / 1.029 GB Notification: Performance of preOpt comSubExp (simulation): time 0.005658/1.433, allocations: 1.709 MB / 1.357 GB, free: 15.92 MB / 1.045 GB Notification: Performance of preOpt resolveLoops (simulation): time 0.001864/1.435, allocations: 0.7949 MB / 1.358 GB, free: 15.12 MB / 1.045 GB Notification: Performance of preOpt evalFunc (simulation): time 0.008227/1.443, allocations: 4.067 MB / 1.362 GB, free: 10.79 MB / 1.045 GB Notification: Performance of preOpt encapsulateWhenConditions (simulation): time 4.343e-05/1.443, allocations: 47.56 kB / 1.362 GB, free: 10.74 MB / 1.045 GB Notification: Performance of pre-optimization done (n=89): time 3.006e-06/1.443, allocations: 0 / 1.362 GB, free: 10.74 MB / 1.045 GB Notification: Performance of matching and sorting (n=97): time 0.01643/1.459, allocations: 5.319 MB / 1.367 GB, free: 5.387 MB / 1.045 GB Notification: Performance of inlineWhenForInitialization (initialization): time 5.179e-05/1.459, allocations: 68.33 kB / 1.367 GB, free: 5.309 MB / 1.045 GB Notification: Performance of selectInitializationVariablesDAE (initialization): time 0.01268/1.472, allocations: 5.511 MB / 1.373 GB, free: 15.82 MB / 1.061 GB Notification: Performance of collectPreVariables (initialization): time 0.0004636/1.473, allocations: 57.7 kB / 1.373 GB, free: 15.76 MB / 1.061 GB Notification: Performance of collectInitialEqns (initialization): time 0.00274/1.475, allocations: 2.064 MB / 1.375 GB, free: 13.71 MB / 1.061 GB Notification: Performance of collectInitialBindings (initialization): time 0.0006225/1.476, allocations: 373.7 kB / 1.375 GB, free: 13.35 MB / 1.061 GB Notification: Performance of simplifyInitialFunctions (initialization): time 0.002335/1.478, allocations: 0.6713 MB / 1.376 GB, free: 12.67 MB / 1.061 GB Notification: Performance of setup shared object (initialization): time 0.0001653/1.479, allocations: 301.1 kB / 1.376 GB, free: 12.37 MB / 1.061 GB Notification: Performance of preBalanceInitialSystem (initialization): time 0.003865/1.482, allocations: 1.641 MB / 1.378 GB, free: 10.72 MB / 1.061 GB Notification: Performance of partitionIndependentBlocks (initialization): time 0.00436/1.487, allocations: 2.463 MB / 1.38 GB, free: 7.953 MB / 1.061 GB Notification: Performance of analyzeInitialSystem (initialization): time 0.006977/1.494, allocations: 3.761 MB / 1.384 GB, free: 3.961 MB / 1.061 GB Notification: Performance of solveInitialSystemEqSystem (initialization): time 1.847e-05/1.494, allocations: 4 kB / 1.384 GB, free: 3.957 MB / 1.061 GB Notification: Performance of matching and sorting (n=391) (initialization): time 0.009875/1.504, allocations: 4.827 MB / 1.388 GB, free: 15.12 MB / 1.076 GB Notification: Performance of prepare postOptimizeDAE: time 3.552e-05/1.504, allocations: 12.84 kB / 1.388 GB, free: 15.11 MB / 1.076 GB Notification: Performance of postOpt simplifyComplexFunction (initialization): time 3.689e-05/1.504, allocations: 16 kB / 1.388 GB, free: 15.09 MB / 1.076 GB Notification: Performance of postOpt tearingSystem (initialization): time 0.0011/1.505, allocations: 483.2 kB / 1.389 GB, free: 14.61 MB / 1.076 GB Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.002412/1.507, allocations: 0.5603 MB / 1.389 GB, free: 14.05 MB / 1.076 GB Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 0.005564/1.513, allocations: 6.274 MB / 1.396 GB, free: 7.312 MB / 1.076 GB Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.003844/1.517, allocations: 188.1 kB / 1.396 GB, free: 7.129 MB / 1.076 GB Notification: Performance of postOpt collapseArrayExpressions (initialization): time 0.0003389/1.517, allocations: 135.9 kB / 1.396 GB, free: 6.996 MB / 1.076 GB Notification: Performance of preBalanceInitialSystem (initialization_lambda0): time 0.005008/1.522, allocations: 2.566 MB / 1.398 GB, free: 4.422 MB / 1.076 GB Notification: Performance of partitionIndependentBlocks (initialization_lambda0): time 0.003602/1.526, allocations: 2.319 MB / 1.401 GB, free: 1.801 MB / 1.076 GB Notification: Performance of analyzeInitialSystem (initialization_lambda0): time 0.006016/1.532, allocations: 3.473 MB / 1.404 GB, free: 14.09 MB / 1.092 GB Notification: Performance of solveInitialSystemEqSystem (initialization_lambda0): time 2.27e-05/1.532, allocations: 8 kB / 1.404 GB, free: 14.09 MB / 1.092 GB Notification: Performance of matching and sorting (n=391) (initialization_lambda0): time 0.009078/1.541, allocations: 4.56 MB / 1.408 GB, free: 9.52 MB / 1.092 GB Notification: Performance of prepare postOptimizeDAE: time 2.462e-05/1.541, allocations: 13.72 kB / 1.408 GB, free: 9.508 MB / 1.092 GB Notification: Performance of postOpt simplifyComplexFunction (initialization): time 0.0001131/1.541, allocations: 16 kB / 1.408 GB, free: 9.492 MB / 1.092 GB Notification: Performance of postOpt tearingSystem (initialization): time 0.001182/1.542, allocations: 0.5114 MB / 1.409 GB, free: 8.969 MB / 1.092 GB Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.002051/1.544, allocations: 0.5227 MB / 1.41 GB, free: 8.445 MB / 1.092 GB Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 0.01154/1.556, allocations: 10.62 MB / 1.42 GB, free: 13.2 MB / 1.107 GB Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.003986/1.56, allocations: 191.9 kB / 1.42 GB, free: 13.01 MB / 1.107 GB Notification: Performance of postOpt collapseArrayExpressions (initialization): time 0.0004587/1.56, allocations: 124 kB / 1.42 GB, free: 12.89 MB / 1.107 GB Notification: Model statistics after passing the back-end for initialization: * Number of independent subsystems: 82 * Number of states: 0 () * Number of discrete variables: 0 () * Number of discrete states: 0 () * Number of clocked states: 0 () * Top-level inputs: 0 Notification: Strong component statistics for initialization (274): * Single equations (assignments): 263 * Array equations: 3 * Algorithm blocks: 0 * Record equations: 3 * When equations: 0 * If-equations: 0 * Equation systems (not torn): 1 * Torn equation systems: 4 * Mixed (continuous/discrete) equation systems: 0 Notification: Equation system details (not torn): * Constant Jacobian (size): 0 systems * Linear Jacobian (size,density): 0 systems * Non-linear Jacobian (size): 1 system {1} * Without analytic Jacobian (size): 0 systems 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): 4 systems {(1,2), (1,2), (1,2), (1,4)} Notification: Performance of prepare postOptimizeDAE: time 0.0008111/1.561, allocations: 323 kB / 1.42 GB, free: 12.57 MB / 1.107 GB Notification: Performance of postOpt lateInlineFunction (simulation): time 0.0014/1.563, allocations: 464.8 kB / 1.421 GB, free: 12.11 MB / 1.107 GB Notification: Performance of postOpt wrapFunctionCalls (simulation): time 0.006776/1.569, allocations: 2.422 MB / 1.423 GB, free: 9.691 MB / 1.107 GB Notification: Performance of postOpt inlineArrayEqn (simulation): time 2.547e-05/1.57, allocations: 12 kB / 1.423 GB, free: 9.68 MB / 1.107 GB Notification: Performance of postOpt constantLinearSystem (simulation): time 6.692e-06/1.57, allocations: 0 / 1.423 GB, free: 9.68 MB / 1.107 GB Notification: Performance of postOpt simplifysemiLinear (simulation): time 0.004554/1.574, allocations: 2.05 MB / 1.425 GB, free: 7.543 MB / 1.107 GB Notification: Performance of postOpt removeSimpleEquations (simulation): time 0.01296/1.587, allocations: 5.245 MB / 1.43 GB, free: 2.25 MB / 1.107 GB Notification: Performance of postOpt simplifyComplexFunction (simulation): time 8.836e-06/1.587, allocations: 128 / 1.43 GB, free: 2.25 MB / 1.107 GB Notification: Performance of postOpt solveSimpleEquations (simulation): time 0.001601/1.589, allocations: 306 kB / 1.431 GB, free: 1.953 MB / 1.107 GB Notification: Performance of postOpt tearingSystem (simulation): time 0.0003749/1.589, allocations: 156.6 kB / 1.431 GB, free: 1.797 MB / 1.107 GB Notification: Performance of postOpt inputDerivativesUsed (simulation): time 0.0001239/1.589, allocations: 43.97 kB / 1.431 GB, free: 1.754 MB / 1.107 GB Notification: Performance of postOpt calculateStrongComponentJacobians (simulation): time 0.001054/1.59, allocations: 1.384 MB / 1.432 GB, free: 328 kB / 1.107 GB Notification: Performance of postOpt calculateStateSetsJacobians (simulation): time 3.597e-06/1.59, allocations: 4 kB / 1.432 GB, free: 324 kB / 1.107 GB Notification: Performance of postOpt symbolicJacobian (simulation): time 0.008077/1.598, allocations: 3.326 MB / 1.436 GB, free: 12.96 MB / 1.123 GB Notification: Performance of postOpt removeConstants (simulation): time 0.002442/1.601, allocations: 0.7281 MB / 1.436 GB, free: 12.21 MB / 1.123 GB Notification: Performance of postOpt simplifyTimeIndepFuncCalls (simulation): time 0.001744/1.603, allocations: 28 kB / 1.436 GB, free: 12.18 MB / 1.123 GB Notification: Performance of postOpt simplifyAllExpressions (simulation): time 0.003163/1.606, allocations: 131.9 kB / 1.436 GB, free: 12.05 MB / 1.123 GB Notification: Performance of postOpt findZeroCrossings (simulation): time 0.0001744/1.606, allocations: 72.91 kB / 1.436 GB, free: 11.98 MB / 1.123 GB Notification: Performance of postOpt collapseArrayExpressions (simulation): time 0.0002058/1.606, allocations: 59.94 kB / 1.437 GB, free: 11.92 MB / 1.123 GB Notification: Performance of sorting global known variables: time 0.008333/1.615, allocations: 3.755 MB / 1.44 GB, free: 8.191 MB / 1.123 GB Notification: Performance of sort global known variables: time 3.41e-07/1.615, allocations: 0 / 1.44 GB, free: 8.191 MB / 1.123 GB Notification: Performance of remove unused functions: time 0.008363/1.623, allocations: 1.865 MB / 1.442 GB, free: 6.328 MB / 1.123 GB Notification: Model statistics after passing the back-end for simulation: * Number of independent subsystems: 5 * Number of states: 3 (pump_y.vol.dynBal.U,pump_dp.vol.dynBal.U,pump_m_flow.vol.dynBal.U) * Number of discrete variables: 0 () * Number of discrete states: 0 () * Number of clocked states: 0 () * Top-level inputs: 0 Notification: Strong component statistics for simulation (110): * Single equations (assignments): 100 * Array equations: 0 * Algorithm blocks: 0 * Record equations: 8 * When equations: 0 * If-equations: 0 * Equation systems (not torn): 1 * Torn equation systems: 1 * Mixed (continuous/discrete) equation systems: 0 Notification: Equation system details (not torn): * Constant Jacobian (size): 0 systems * Linear Jacobian (size,density): 0 systems * Non-linear Jacobian (size): 1 system {1} * Without analytic Jacobian (size): 0 systems 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): 1 system {(1,5)} Notification: Performance of Backend phase and start with SimCode phase: time 0.002785/1.626, allocations: 0.8889 MB / 1.443 GB, free: 5.488 MB / 1.123 GB Notification: Performance of simCode: created initialization part: time 0.01279/1.639, allocations: 5.805 MB / 1.449 GB, free: 15.6 MB / 1.139 GB Notification: Performance of simCode: created event and clocks part: time 2.033e-05/1.639, allocations: 4 kB / 1.449 GB, free: 15.6 MB / 1.139 GB Notification: Performance of simCode: created simulation system equations: time 0.003509/1.642, allocations: 0.869 MB / 1.449 GB, free: 14.73 MB / 1.139 GB Notification: Performance of simCode: created of all other equations (e.g. parameter, nominal, assert, etc): time 0.0155/1.658, allocations: 2.496 MB / 1.452 GB, free: 12.31 MB / 1.139 GB Notification: Performance of simCode: created linear, non-linear and system jacobian parts: time 0.0168/1.675, allocations: 7.867 MB / 1.46 GB, free: 4.406 MB / 1.139 GB Notification: Performance of simCode: some other stuff during SimCode phase: time 0.0041/1.679, allocations: 2.742 MB / 1.462 GB, free: 1.633 MB / 1.139 GB Notification: Performance of simCode: alias equations: time 0.0054/1.684, allocations: 1.18 MB / 1.463 GB, free: 456 kB / 1.139 GB Notification: Performance of simCode: all other stuff during SimCode phase: time 0.001275/1.685, allocations: 327.3 kB / 1.464 GB, free: 128 kB / 1.139 GB Notification: Performance of SimCode: time 1.222e-06/1.686, allocations: 0 / 1.464 GB, free: 128 kB / 1.139 GB Notification: Performance of Templates: time 0.1639/1.849, allocations: 98.04 MB / 1.559 GB, free: 15.45 MB / 1.248 GB make -j1 -f Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified.makefile (rm -f Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified.pipe ; mkfifo Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified.pipe ; head -c 1048576 < Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified.pipe >> ../files/Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified.sim & ./Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified -abortSlowSimulation -alarm=480 -emit_protected -lv LOG_STATS > Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified.pipe 2>&1) diffSimulationResults("Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified_res.mat","/mnt/ReferenceFiles/Buildings/csv/maint_10.0.x/Buildings_Fluid_Movers_Validation_PowerSimplified.csv","/var/lib/jenkins/ws/OpenModelicaLibraryTestingWork/OpenModelicaLibraryTesting/files/Buildings_10_Buildings.Fluid.Movers.Validation.PowerSimplified.diff",relTol=0.003,relTolDiffMinMax=0.003,rangeDelta=0.001) Reference file matches