Running: ./testmodel.py --libraries=/home/hudson/saved_omc/libraries/.openmodelica/libraries --ompython_omhome=/usr Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan.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 9.1.3-maint.9.1.x/package.mo", uses=false) Using package Buildings with version 9.1.3 (/home/hudson/saved_omc/libraries/.openmodelica/libraries/Buildings 9.1.3-maint.9.1.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.FMI.Validation.HeaterFan,tolerance=1e-06,outputFormat="mat",numberOfIntervals=5000,variableFilter="time|hea.com.vol.T|sou.T_in|sin.T_in|floMac.inlet.p|floMac.outlet.p|hea.inlet.p|hea.outlet.p|sou.outlet.p|sin.inlet.p",fileNamePrefix="Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan") translateModel(Buildings.Fluid.FMI.Validation.HeaterFan,tolerance=1e-06,outputFormat="mat",numberOfIntervals=5000,variableFilter="time|hea.com.vol.T|sou.T_in|sin.T_in|floMac.inlet.p|floMac.outlet.p|hea.inlet.p|hea.outlet.p|sou.outlet.p|sin.inlet.p",fileNamePrefix="Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan") Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/ModelicaServices 4.0.0+maint.om/package.mo): time 0.001571/0.001571, allocations: 105 kB / 15.98 MB, free: 6.77 MB / 14.72 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Complex 4.0.0+maint.om/package.mo): time 0.00185/0.00185, allocations: 194.2 kB / 16.91 MB, free: 6.551 MB / 14.72 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Modelica 4.0.0+maint.om/package.mo): time 1.54/1.54, allocations: 222.9 MB / 240.6 MB, free: 4.512 MB / 190.1 MB Notification: Performance of loadFile(/home/hudson/saved_omc/libraries/.openmodelica/libraries/Buildings 9.1.3-maint.9.1.x/package.mo): time 2.389/2.389, allocations: 390.2 MB / 0.665 GB, free: 0.4922 MB / 0.5137 GB Notification: Performance of FrontEnd - loaded program: time 0.002713/0.002714, allocations: 63.91 kB / 0.8127 GB, free: 14.77 MB / 0.67 GB Notification: Performance of FrontEnd - Absyn->SCode: time 0.7524/0.7552, allocations: 140.4 MB / 0.9498 GB, free: 9.086 MB / 0.7169 GB Notification: Performance of NFInst.instantiate(Buildings.Fluid.FMI.Validation.HeaterFan): time 1.013/1.768, allocations: 308.7 MB / 1.251 GB, free: 25.21 MB / 0.9981 GB Notification: Performance of NFInst.instExpressions: time 0.03473/1.803, allocations: 27.29 MB / 1.278 GB, free: 25.16 MB / 0.9981 GB Notification: Performance of NFInst.updateImplicitVariability: time 0.003855/1.807, allocations: 74.19 kB / 1.278 GB, free: 25.16 MB / 0.9981 GB Notification: Performance of NFTyping.typeComponents: time 0.004509/1.811, allocations: 1.422 MB / 1.279 GB, free: 25.13 MB / 0.9981 GB Notification: Performance of NFTyping.typeBindings: time 0.00875/1.82, allocations: 2.826 MB / 1.282 GB, free: 25.03 MB / 0.9981 GB Notification: Performance of NFTyping.typeClassSections: time 0.008347/1.828, allocations: 2.429 MB / 1.284 GB, free: 24.96 MB / 0.9981 GB Notification: Performance of NFFlatten.flatten: time 0.008865/1.837, allocations: 4.619 MB / 1.289 GB, free: 24.95 MB / 0.9981 GB Notification: Performance of NFFlatten.resolveConnections: time 0.004604/1.842, allocations: 2.041 MB / 1.291 GB, free: 24.71 MB / 0.9981 GB Notification: Performance of NFEvalConstants.evaluate: time 0.006272/1.848, allocations: 2.41 MB / 1.293 GB, free: 24.7 MB / 0.9981 GB Notification: Performance of NFSimplifyModel.simplify: time 0.004029/1.852, allocations: 1.537 MB / 1.295 GB, free: 24.7 MB / 0.9981 GB Notification: Performance of NFPackage.collectConstants: time 0.0008939/1.853, allocations: 248 kB / 1.295 GB, free: 24.7 MB / 0.9981 GB Notification: Performance of NFFlatten.collectFunctions: time 0.008568/1.862, allocations: 3.537 MB / 1.299 GB, free: 24.66 MB / 0.9981 GB Notification: Performance of NFScalarize.scalarize: time 0.001482/1.863, allocations: 0.6946 MB / 1.299 GB, free: 24.66 MB / 0.9981 GB Notification: Performance of NFVerifyModel.verify: time 0.003638/1.867, allocations: 1.201 MB / 1.3 GB, free: 24.66 MB / 0.9981 GB Notification: Performance of NFConvertDAE.convert: time 0.00706/1.874, allocations: 3.692 MB / 1.304 GB, free: 24.44 MB / 0.9981 GB Notification: Performance of FrontEnd - DAE generated: time 7.103e-06/1.874, allocations: 0 / 1.304 GB, free: 24.44 MB / 0.9981 GB Notification: Performance of FrontEnd: time 2.053e-06/1.874, allocations: 0.875 kB / 1.304 GB, free: 24.44 MB / 0.9981 GB Notification: Performance of Transformations before backend: time 0.000152/1.874, allocations: 0 / 1.304 GB, free: 24.44 MB / 0.9981 GB Notification: Model statistics after passing the front-end and creating the data structures used by the back-end: * Number of equations: 328 * Number of variables: 328 Notification: Performance of Generate backend data structure: time 0.007478/1.882, allocations: 2.498 MB / 1.306 GB, free: 23.2 MB / 0.9981 GB Notification: Performance of prepare preOptimizeDAE: time 4.18e-05/1.882, allocations: 11.06 kB / 1.306 GB, free: 23.2 MB / 0.9981 GB Notification: Performance of preOpt normalInlineFunction (simulation): time 0.0065/1.888, allocations: 0.8987 MB / 1.307 GB, free: 23.09 MB / 0.9981 GB Notification: Performance of preOpt evaluateParameters (simulation): time 0.004948/1.893, allocations: 2.061 MB / 1.309 GB, free: 22.63 MB / 0.9981 GB Notification: Performance of preOpt simplifyIfEquations (simulation): time 0.000721/1.894, allocations: 213.4 kB / 1.31 GB, free: 22.62 MB / 0.9981 GB Notification: Performance of preOpt expandDerOperator (simulation): time 0.0005176/1.895, allocations: 135.3 kB / 1.31 GB, free: 22.62 MB / 0.9981 GB Notification: Performance of preOpt clockPartitioning (simulation): time 0.004788/1.899, allocations: 1.676 MB / 1.311 GB, free: 22.46 MB / 0.9981 GB Notification: Performance of preOpt findStateOrder (simulation): time 4.024e-05/1.899, allocations: 5.781 kB / 1.311 GB, free: 22.46 MB / 0.9981 GB Notification: Performance of preOpt replaceEdgeChange (simulation): time 0.0002311/1.9, allocations: 58.11 kB / 1.311 GB, free: 22.46 MB / 0.9981 GB Notification: Performance of preOpt inlineArrayEqn (simulation): time 5.433e-05/1.9, allocations: 48.77 kB / 1.311 GB, free: 22.45 MB / 0.9981 GB Notification: Performance of preOpt removeEqualRHS (simulation): time 0.004383/1.904, allocations: 1.574 MB / 1.313 GB, free: 22.44 MB / 0.9981 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 0.01213/1.916, allocations: 7.444 MB / 1.32 GB, free: 18.97 MB / 0.9981 GB Notification: Performance of preOpt comSubExp (simulation): time 0.002541/1.919, allocations: 0.6975 MB / 1.321 GB, free: 18.93 MB / 0.9981 GB Notification: Performance of preOpt resolveLoops (simulation): time 0.0008598/1.92, allocations: 330.4 kB / 1.321 GB, free: 18.91 MB / 0.9981 GB Notification: Performance of preOpt evalFunc (simulation): time 0.000262/1.92, allocations: 194.4 kB / 1.321 GB, free: 18.72 MB / 0.9981 GB Notification: Performance of preOpt encapsulateWhenConditions (simulation): time 2.197e-05/1.92, allocations: 38.94 kB / 1.321 GB, free: 18.68 MB / 0.9981 GB Notification: Performance of preOpt simplifyInStream (simulation): time 0.0008907/1.921, allocations: 91.34 kB / 1.322 GB, free: 18.62 MB / 0.9981 GB Notification: Performance of pre-optimization done (n=37): time 5.02e-06/1.921, allocations: 0 / 1.322 GB, free: 18.62 MB / 0.9981 GB Notification: Performance of matching and sorting (n=37): time 0.003635/1.925, allocations: 1.407 MB / 1.323 GB, free: 18.07 MB / 0.9981 GB Notification: Performance of inlineWhenForInitialization (initialization): time 3.031e-05/1.925, allocations: 57.53 kB / 1.323 GB, free: 18 MB / 0.9981 GB Notification: Performance of selectInitializationVariablesDAE (initialization): time 0.003673/1.928, allocations: 1.854 MB / 1.325 GB, free: 17.77 MB / 0.9981 GB Notification: Performance of collectPreVariables (initialization): time 0.0001072/1.928, allocations: 35.55 kB / 1.325 GB, free: 17.74 MB / 0.9981 GB Notification: Performance of collectInitialEqns (initialization): time 0.0006421/1.929, allocations: 0.8212 MB / 1.326 GB, free: 17.5 MB / 0.9981 GB Notification: Performance of collectInitialBindings (initialization): time 0.00012/1.929, allocations: 129.8 kB / 1.326 GB, free: 17.41 MB / 0.9981 GB Notification: Performance of simplifyInitialFunctions (initialization): time 0.0003254/1.93, allocations: 149.7 kB / 1.326 GB, free: 17.39 MB / 0.9981 GB Notification: Performance of setup shared object (initialization): time 6.065e-05/1.93, allocations: 328.6 kB / 1.326 GB, free: 17.09 MB / 0.9981 GB Notification: Performance of preBalanceInitialSystem (initialization): time 0.001337/1.931, allocations: 447.1 kB / 1.327 GB, free: 17.07 MB / 0.9981 GB Notification: Performance of partitionIndependentBlocks (initialization): time 0.001412/1.932, allocations: 0.6652 MB / 1.327 GB, free: 16.77 MB / 0.9981 GB Notification: Performance of analyzeInitialSystem (initialization): time 0.00216/1.935, allocations: 0.9159 MB / 1.328 GB, free: 16.51 MB / 0.9981 GB Notification: Performance of solveInitialSystemEqSystem (initialization): time 1.07e-05/1.935, allocations: 2.719 kB / 1.328 GB, free: 16.51 MB / 0.9981 GB Notification: Performance of matching and sorting (n=74) (initialization): time 0.003591/1.938, allocations: 1.44 MB / 1.33 GB, free: 16.14 MB / 0.9981 GB Notification: Performance of prepare postOptimizeDAE: time 2.688e-05/1.938, allocations: 5.969 kB / 1.33 GB, free: 16.14 MB / 0.9981 GB Notification: Performance of postOpt simplifyComplexFunction (initialization): time 2.246e-05/1.938, allocations: 12.14 kB / 1.33 GB, free: 16.14 MB / 0.9981 GB Notification: Performance of postOpt tearingSystem (initialization): time 0.000231/1.938, allocations: 68.22 kB / 1.33 GB, free: 16.12 MB / 0.9981 GB Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.001212/1.94, allocations: 219.1 kB / 1.33 GB, free: 16.11 MB / 0.9981 GB Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 0.001652/1.941, allocations: 3.131 MB / 1.333 GB, free: 13.12 MB / 0.9981 GB Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.002489/1.944, allocations: 264.8 kB / 1.333 GB, free: 13.09 MB / 0.9981 GB Notification: Performance of postOpt collapseArrayExpressions (initialization): time 0.0001258/1.944, allocations: 38.42 kB / 1.333 GB, free: 13.09 MB / 0.9981 GB Notification: Performance of preBalanceInitialSystem (initialization_lambda0): time 0.001991/1.946, allocations: 0.7844 MB / 1.334 GB, free: 12.99 MB / 0.9981 GB Notification: Performance of partitionIndependentBlocks (initialization_lambda0): time 0.001358/1.947, allocations: 0.6255 MB / 1.335 GB, free: 12.7 MB / 0.9981 GB Notification: Performance of analyzeInitialSystem (initialization_lambda0): time 0.001879/1.949, allocations: 0.8595 MB / 1.335 GB, free: 12.43 MB / 0.9981 GB Notification: Performance of solveInitialSystemEqSystem (initialization_lambda0): time 8.265e-06/1.949, allocations: 3.656 kB / 1.335 GB, free: 12.43 MB / 0.9981 GB Notification: Performance of matching and sorting (n=74) (initialization_lambda0): time 0.003865/1.953, allocations: 1.374 MB / 1.337 GB, free: 12.07 MB / 0.9981 GB Notification: Performance of prepare postOptimizeDAE: time 2.52e-05/1.953, allocations: 7.969 kB / 1.337 GB, free: 12.07 MB / 0.9981 GB Notification: Performance of postOpt simplifyComplexFunction (initialization): time 1.505e-05/1.953, allocations: 6.188 kB / 1.337 GB, free: 12.07 MB / 0.9981 GB Notification: Performance of postOpt tearingSystem (initialization): time 0.0001932/1.953, allocations: 65.09 kB / 1.337 GB, free: 12.04 MB / 0.9981 GB Notification: Performance of postOpt solveSimpleEquations (initialization): time 0.00117/1.955, allocations: 210.9 kB / 1.337 GB, free: 12.04 MB / 0.9981 GB Notification: Performance of postOpt calculateStrongComponentJacobians (initialization): time 0.001945/1.957, allocations: 3.132 MB / 1.34 GB, free: 9.051 MB / 0.9981 GB Notification: Performance of postOpt simplifyAllExpressions (initialization): time 0.002616/1.959, allocations: 223.9 kB / 1.34 GB, free: 9.027 MB / 0.9981 GB Notification: Performance of postOpt collapseArrayExpressions (initialization): time 0.0001292/1.959, allocations: 38.45 kB / 1.34 GB, free: 9.023 MB / 0.9981 GB Notification: Model statistics after passing the back-end for initialization: * Number of independent subsystems: 28 * 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 (69): * Single equations (assignments): 66 * Array equations: 1 * Algorithm blocks: 0 * Record equations: 0 * When equations: 0 * If-equations: 0 * Equation systems (not torn): 0 * Torn equation systems: 2 * Mixed (continuous/discrete) equation systems: 0 Notification: Torn system details for strict tearing set: * Linear torn systems (#iteration vars, #inner vars, density): 2 systems {(1,2,100.0%), (1,2,100.0%)} * Non-linear torn systems (#iteration vars, #inner vars): 0 systems Notification: Performance of prepare postOptimizeDAE: time 0.0004081/1.96, allocations: 218.2 kB / 1.341 GB, free: 8.84 MB / 0.9981 GB Notification: Performance of postOpt lateInlineFunction (simulation): time 0.0006002/1.96, allocations: 163.3 kB / 1.341 GB, free: 8.754 MB / 0.9981 GB Notification: Performance of postOpt wrapFunctionCalls (simulation): time 0.002679/1.963, allocations: 0.9954 MB / 1.342 GB, free: 8.445 MB / 0.9981 GB Notification: Performance of postOpt inlineArrayEqn (simulation): time 6.943e-06/1.963, allocations: 2.375 kB / 1.342 GB, free: 8.445 MB / 0.9981 GB Notification: Performance of postOpt constantLinearSystem (simulation): time 5.971e-06/1.963, allocations: 6.719 kB / 1.342 GB, free: 8.445 MB / 0.9981 GB Notification: Performance of postOpt simplifysemiLinear (simulation): time 6.302e-06/1.963, allocations: 3.047 kB / 1.342 GB, free: 8.445 MB / 0.9981 GB Notification: Performance of postOpt removeSimpleEquations (simulation): time 0.004584/1.968, allocations: 2.175 MB / 1.344 GB, free: 7.859 MB / 0.9981 GB Notification: Performance of postOpt simplifyComplexFunction (simulation): time 5.36e-06/1.968, allocations: 1.562 kB / 1.344 GB, free: 7.859 MB / 0.9981 GB Notification: Performance of postOpt solveSimpleEquations (simulation): time 0.0007087/1.968, allocations: 110.2 kB / 1.344 GB, free: 7.852 MB / 0.9981 GB Notification: Performance of postOpt tearingSystem (simulation): time 0.0001335/1.969, allocations: 61.61 kB / 1.344 GB, free: 7.832 MB / 0.9981 GB Notification: Performance of postOpt inputDerivativesUsed (simulation): time 4.657e-05/1.969, allocations: 11.83 kB / 1.344 GB, free: 7.832 MB / 0.9981 GB Notification: Performance of postOpt calculateStrongComponentJacobians (simulation): time 0.001493/1.97, allocations: 3.134 MB / 1.347 GB, free: 4.852 MB / 0.9981 GB Notification: Performance of postOpt calculateStateSetsJacobians (simulation): time 2.775e-06/1.97, allocations: 2.719 kB / 1.347 GB, free: 4.852 MB / 0.9981 GB Notification: Performance of postOpt symbolicJacobian (simulation): time 0.002285/1.972, allocations: 1.059 MB / 1.348 GB, free: 4.355 MB / 0.9981 GB Notification: Performance of postOpt removeConstants (simulation): time 0.0007368/1.973, allocations: 318.3 kB / 1.348 GB, free: 4.176 MB / 0.9981 GB Notification: Performance of postOpt simplifyTimeIndepFuncCalls (simulation): time 0.0004283/1.974, allocations: 8.391 kB / 1.348 GB, free: 4.176 MB / 0.9981 GB Notification: Performance of postOpt simplifyAllExpressions (simulation): time 0.001538/1.975, allocations: 138.8 kB / 1.349 GB, free: 4.156 MB / 0.9981 GB Notification: Performance of postOpt findZeroCrossings (simulation): time 6.294e-05/1.975, allocations: 26.62 kB / 1.349 GB, free: 4.156 MB / 0.9981 GB Notification: Performance of postOpt collapseArrayExpressions (simulation): time 5.904e-05/1.975, allocations: 18.62 kB / 1.349 GB, free: 4.156 MB / 0.9981 GB Notification: Performance of sorting global known variables: time 0.002592/1.978, allocations: 1.321 MB / 1.35 GB, free: 4.004 MB / 0.9981 GB Notification: Performance of sort global known variables: time 4.61e-07/1.978, allocations: 2.531 kB / 1.35 GB, free: 4.004 MB / 0.9981 GB Notification: Performance of remove unused functions: time 0.002998/1.981, allocations: 0.7691 MB / 1.351 GB, free: 3.91 MB / 0.9981 GB Notification: Model statistics after passing the back-end for simulation: * Number of independent subsystems: 5 * 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 simulation (33): * Single equations (assignments): 31 * Array equations: 0 * Algorithm blocks: 0 * Record equations: 0 * When equations: 0 * If-equations: 0 * Equation systems (not torn): 0 * Torn equation systems: 2 * Mixed (continuous/discrete) equation systems: 0 Notification: Torn system details for strict tearing set: * Linear torn systems (#iteration vars, #inner vars, density): 2 systems {(1,2,100.0%), (1,2,100.0%)} * Non-linear torn systems (#iteration vars, #inner vars): 0 systems Notification: Performance of Backend phase and start with SimCode phase: time 0.0008021/1.982, allocations: 312.6 kB / 1.351 GB, free: 3.773 MB / 0.9981 GB Notification: Performance of simCode: created initialization part: time 0.004276/1.986, allocations: 1.798 MB / 1.353 GB, free: 3.285 MB / 0.9981 GB Notification: Performance of simCode: created event and clocks part: time 7.314e-06/1.986, allocations: 2.125 kB / 1.353 GB, free: 3.285 MB / 0.9981 GB Notification: Performance of simCode: created simulation system equations: time 0.0009619/1.987, allocations: 0.5253 MB / 1.353 GB, free: 3.055 MB / 0.9981 GB Notification: Performance of simCode: created of all other equations (e.g. parameter, nominal, assert, etc): time 0.004911/1.992, allocations: 1.025 MB / 1.354 GB, free: 2.855 MB / 0.9981 GB Notification: Performance of simCode: created linear, non-linear and system jacobian parts: time 0.005835/1.998, allocations: 3.359 MB / 1.357 GB, free: 1.188 MB / 0.9981 GB Notification: Performance of simCode: some other stuff during SimCode phase: time 0.001214/1.999, allocations: 1.345 MB / 1.359 GB, free: 468 kB / 0.9981 GB Notification: Performance of simCode: all other stuff during SimCode phase: time 0.0006167/2, allocations: 132.3 kB / 1.359 GB, free: 460 kB / 0.9981 GB Notification: Performance of SimCode: time 7.81e-07/2, allocations: 0 / 1.359 GB, free: 460 kB / 0.9981 GB Notification: Performance of Templates: time 0.06246/2.062, allocations: 48.75 MB / 1.406 GB, free: 7.805 MB / 1.045 GB make -j1 -f Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan.makefile (rm -f Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan.pipe ; mkfifo Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan.pipe ; head -c 1048576 < Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan.pipe >> ../files/Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan.sim & ./Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan -abortSlowSimulation -alarm=480 -emit_protected -lv LOG_STATS > Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan.pipe 2>&1) diffSimulationResults("Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan_res.mat","/mnt/ReferenceFiles/Buildings/csv/maint_9.1.x/Buildings_Fluid_FMI_Validation_HeaterFan.csv","/var/lib/jenkins1/ws/OpenModelicaLibraryTestingWork/OpenModelicaLibraryTesting/files/Buildings_9_Buildings.Fluid.FMI.Validation.HeaterFan.diff",relTol=0.003,relTolDiffMinMax=0.003,rangeDelta=0.001) Reference file matches