diff --git a/ProcessLib/SmallDeformation/Tests.cmake b/ProcessLib/SmallDeformation/Tests.cmake
index ce27a7c5e4ea2b7621135952673bb6dfa5b4a6a4..089190945330bf53b851c5b1371733049c7dc269 100644
--- a/ProcessLib/SmallDeformation/Tests.cmake
+++ b/ProcessLib/SmallDeformation/Tests.cmake
@@ -52,6 +52,9 @@ endif()
if (OGS_USE_MPI)
# OgsTest(WRAPPER mpirun -np 4 PROJECTFILE Mechanics/Linear/disc_with_hole.prj)
OgsTest(WRAPPER mpirun -np 2 PROJECTFILE Mechanics/InitialStates/soil_column_nonequilibrium_sigma_elementwise.prj)
+ OgsTest(PROJECTFILE Mechanics/Ehlers/cube_1e0_SNES.prj)
+ OgsTest(PROJECTFILE Mechanics/Linear/square_1e0_SNES.prj)
+ OgsTest(PROJECTFILE Mechanics/Linear/cube_1e0_SNES.prj)
endif()
if (OGS_USE_MFRONT)
diff --git a/Tests/Data/Mechanics/Ehlers/cube_1e0_SNES.prj b/Tests/Data/Mechanics/Ehlers/cube_1e0_SNES.prj
new file mode 100644
index 0000000000000000000000000000000000000000..6cb996ecada7e225c32534ce5e974e562c3d673f
--- /dev/null
+++ b/Tests/Data/Mechanics/Ehlers/cube_1e0_SNES.prj
@@ -0,0 +1,340 @@
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<OpenGeoSysProject>
+ <mesh>cube_1x1x1_hex_1e0.vtu</mesh>
+ <geometry>cube_1x1x1.gml</geometry>
+ <processes>
+ <process>
+ <name>SD</name>
+ <type>SMALL_DEFORMATION</type>
+ <integration_order>2</integration_order>
+ <constitutive_relation>
+ <type>Ehlers</type>
+ <shear_modulus>G</shear_modulus>
+ <bulk_modulus>K</bulk_modulus>
+ <kappa>kappa</kappa>
+ <beta>beta</beta>
+ <gamma>gamma</gamma>
+ <hardening_modulus>hard</hardening_modulus>
+ <alpha>alpha</alpha>
+ <delta>delta</delta>
+ <eps>epsilon</eps>
+ <m>m</m>
+ <alphap>alphap</alphap>
+ <deltap>deltap</deltap>
+ <epsp>epsilonp</epsp>
+ <mp>mp</mp>
+ <betap>betap</betap>
+ <gammap>gammap</gammap>
+ <tangent_type>Plastic</tangent_type>
+ <nonlinear_solver>
+ <maximum_iterations>100</maximum_iterations>
+ <residuum_tolerance>1e-14</residuum_tolerance>
+ <increment_tolerance>0</increment_tolerance>
+ </nonlinear_solver>
+ </constitutive_relation>
+ <solid_density>rho_sr</solid_density>
+ <specific_body_force>0 0 0</specific_body_force>
+ <process_variables>
+ <process_variable>displacement</process_variable>
+ </process_variables>
+ <secondary_variables>
+ <secondary_variable internal_name="sigma" output_name="sigma"/>
+ <secondary_variable internal_name="epsilon" output_name="epsilon"/>
+ </secondary_variables>
+ </process>
+ </processes>
+ <time_loop>
+ <processes>
+ <process ref="SD">
+ <nonlinear_solver>petsc_snes</nonlinear_solver>
+ <convergence_criterion>
+ <type>DeltaX</type>
+ <norm_type>NORM2</norm_type>
+ <abstol>1e-14</abstol>
+ </convergence_criterion>
+ <time_discretization>
+ <type>BackwardEuler</type>
+ </time_discretization>
+ <time_stepping>
+ <type>FixedTimeStepping</type>
+ <t_initial>0</t_initial>
+ <t_end>5.1</t_end>
+ <timesteps>
+ <pair>
+ <repeat>1</repeat>
+ <delta_t>0.05</delta_t>
+ </pair>
+ <pair>
+ <repeat>1000</repeat>
+ <delta_t>0.025</delta_t>
+ </pair>
+ </timesteps>
+ </time_stepping>
+ </process>
+ </processes>
+ <output>
+ <type>VTK</type>
+ <prefix>cube_1e0</prefix>
+ <timesteps>
+ <pair>
+ <repeat>10000000</repeat>
+ <each_steps>1</each_steps>
+ </pair>
+ </timesteps>
+ <variables>
+ <variable>displacement</variable>
+ <variable>sigma</variable>
+ <variable>epsilon</variable>
+ </variables>
+ <suffix>_ts_{:timestep}_t_{:time}</suffix>
+ </output>
+ </time_loop>
+ <parameters>
+ <parameter>
+ <name>G</name>
+ <type>Constant</type>
+ <value>150.</value>
+ </parameter>
+ <parameter>
+ <name>K</name>
+ <type>Constant</type>
+ <value>200.</value>
+ </parameter>
+ <parameter>
+ <name>kappa</name>
+ <type>Constant</type>
+ <value>0.1</value>
+ </parameter>
+ <parameter>
+ <name>beta</name>
+ <type>Constant</type>
+ <value>0.095</value>
+ </parameter>
+ <parameter>
+ <name>gamma</name>
+ <type>Constant</type>
+ <value>1.</value>
+ </parameter>
+ <parameter>
+ <name>hard</name>
+ <type>Constant</type>
+ <value>0.</value>
+ </parameter>
+ <parameter>
+ <name>alpha</name>
+ <type>Constant</type>
+ <value>0.01</value>
+ </parameter>
+ <parameter>
+ <name>delta</name>
+ <type>Constant</type>
+ <value>0.0078</value>
+ </parameter>
+ <parameter>
+ <name>epsilon</name>
+ <type>Constant</type>
+ <value>0.1</value>
+ </parameter>
+ <parameter>
+ <name>m</name>
+ <type>Constant</type>
+ <value>0.54</value>
+ </parameter>
+ <parameter>
+ <name>alphap</name>
+ <type>Constant</type>
+ <value>0.01</value>
+ </parameter>
+ <parameter>
+ <name>deltap</name>
+ <type>Constant</type>
+ <value>0.0078</value>
+ </parameter>
+ <parameter>
+ <name>epsilonp</name>
+ <type>Constant</type>
+ <value>0.1</value>
+ </parameter>
+ <parameter>
+ <name>mp</name>
+ <type>Constant</type>
+ <value>0.54</value>
+ </parameter>
+ <parameter>
+ <name>betap</name>
+ <type>Constant</type>
+ <value>0.0608</value>
+ </parameter>
+ <parameter>
+ <name>gammap</name>
+ <type>Constant</type>
+ <value>1.</value>
+ </parameter>
+ <parameter>
+ <name>rho_sr</name>
+ <type>Constant</type>
+ <value>1</value>
+ </parameter>
+ <parameter>
+ <name>displacement0</name>
+ <type>Constant</type>
+ <values>0 0 0</values>
+ </parameter>
+ <parameter>
+ <name>Dirichlet_left</name>
+ <type>Constant</type>
+ <value>0.</value>
+ </parameter>
+ <parameter>
+ <name>Dirichlet_bottom</name>
+ <type>Constant</type>
+ <value>0.</value>
+ </parameter>
+ <parameter>
+ <name>Dirichlet_front</name>
+ <type>Constant</type>
+ <value>0.</value>
+ </parameter>
+ <parameter>
+ <name>Dirichlet_top_spatial</name>
+ <type>Constant</type>
+ <value>1</value>
+ </parameter>
+ <parameter>
+ <name>Neumann_spatial</name>
+ <type>Constant</type>
+ <value>1</value>
+ </parameter>
+ <parameter>
+ <name>Dirichlet_top</name>
+ <type>CurveScaled</type>
+ <curve>Dirichlet_top_temporal</curve>
+ <parameter>Dirichlet_top_spatial</parameter>
+ </parameter>
+ <parameter>
+ <name>Neumann_force_right</name>
+ <type>CurveScaled</type>
+ <curve>Neumann_temporal_right</curve>
+ <parameter>Neumann_spatial</parameter>
+ </parameter>
+ <parameter>
+ <name>Neumann_force_top</name>
+ <type>CurveScaled</type>
+ <curve>Neumann_temporal_top</curve>
+ <parameter>Neumann_spatial</parameter>
+ </parameter>
+ </parameters>
+ <curves>
+ <curve>
+ <name>Dirichlet_top_temporal</name>
+ <coords>0.0 0.1 5.1</coords>
+ <values>0.0 0.0 -0.005</values>
+ </curve>
+ <curve>
+ <name>Neumann_temporal_right</name>
+ <coords>0.0 0.1 5.1</coords>
+ <values>0.0 -0.07 -0.02</values>
+ </curve>
+ <curve>
+ <name>Neumann_temporal_top</name>
+ <coords>0.0 0.1 5.1</coords>
+ <values>0 -0.07 -0.02</values>
+ </curve>
+ </curves>
+ <process_variables>
+ <process_variable>
+ <name>displacement</name>
+ <components>3</components>
+ <order>1</order>
+ <initial_condition>displacement0</initial_condition>
+ <boundary_conditions>
+ <!-- fixed boundaries -->
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>left</geometry>
+ <type>Dirichlet</type>
+ <component>0</component>
+ <parameter>Dirichlet_left</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>front</geometry>
+ <type>Dirichlet</type>
+ <component>1</component>
+ <parameter>Dirichlet_front</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>bottom</geometry>
+ <type>Dirichlet</type>
+ <component>2</component>
+ <parameter>Dirichlet_bottom</parameter>
+ </boundary_condition>
+ <!-- force -->
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>right</geometry>
+ <type>Neumann</type>
+ <component>0</component>
+ <parameter>Neumann_force_right</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>back</geometry>
+ <type>Dirichlet</type>
+ <component>1</component>
+ <parameter>Dirichlet_top</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>top</geometry>
+ <type>Neumann</type>
+ <component>2</component>
+ <parameter>Neumann_force_top</parameter>
+ </boundary_condition>
+ </boundary_conditions>
+ </process_variable>
+ </process_variables>
+ <nonlinear_solvers>
+ <nonlinear_solver>
+ <name>petsc_snes</name>
+ <type>PETScSNES</type>
+ <max_iter>50</max_iter>
+ <linear_solver>general_linear_solver</linear_solver>
+ </nonlinear_solver>
+ </nonlinear_solvers>
+ <linear_solvers>
+ <linear_solver>
+ <name>general_linear_solver</name>
+ <petsc>
+ <parameters>-snes_type newtonls -snes_rtol 1e-16 -ksp_type cg -pc_type bjacobi -ksp_rtol 1e-16</parameters>
+ </petsc>
+ </linear_solver>
+ </linear_solvers>
+ <test_definition>
+ <vtkdiff>
+ <file>cube_1e0_ts_101_t_2.550000.vtu</file>
+ <field>displacement</field>
+ <absolute_tolerance>1e-14</absolute_tolerance>
+ <relative_tolerance>0</relative_tolerance>
+ </vtkdiff>
+ <vtkdiff>
+ <file>cube_1e0_ts_101_t_2.550000.vtu</file>
+ <field>sigma</field>
+ <absolute_tolerance>1e-15</absolute_tolerance>
+ <relative_tolerance>0</relative_tolerance>
+ </vtkdiff>
+ <vtkdiff>
+ <file>cube_1e0_ts_203_t_5.100000.vtu</file>
+ <field>displacement</field>
+ <absolute_tolerance>1e-14</absolute_tolerance>
+ <relative_tolerance>0</relative_tolerance>
+ </vtkdiff>
+ <vtkdiff>
+ <file>cube_1e0_ts_203_t_5.100000.vtu</file>
+ <field>sigma</field>
+ <absolute_tolerance>2e-15</absolute_tolerance>
+ <relative_tolerance>0</relative_tolerance>
+ </vtkdiff>
+ </test_definition>
+</OpenGeoSysProject>
diff --git a/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_101_t_2_550000_0.vtu b/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_101_t_2_550000_0.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..2b438af075f2cd2d873b48dd62aecaee8a03f455
--- /dev/null
+++ b/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_101_t_2_550000_0.vtu
@@ -0,0 +1,27 @@
+<?xml version="1.0"?>
+<VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+ <UnstructuredGrid>
+ <Piece NumberOfPoints="8" NumberOfCells="1" >
+ <PointData>
+ <DataArray type="Float64" Name="displacement" NumberOfComponents="3" format="appended" RangeMin="0" RangeMax="0.0026676085653" offset="0" />
+ <DataArray type="Float64" Name="sigma" NumberOfComponents="6" format="appended" RangeMin="0.28704467504" RangeMax="0.28704467504" offset="104" />
+ <DataArray type="Float64" Name="epsilon" NumberOfComponents="6" format="appended" RangeMin="0.0026676085653" RangeMax="0.0026676085653" offset="340" />
+ </PointData>
+ <CellData>
+ </CellData>
+ <Points>
+ <DataArray type="Float64" Name="Points" NumberOfComponents="3" format="appended" RangeMin="0" RangeMax="1.7320508076" offset="544" />
+ </Points>
+ <Cells>
+ <DataArray type="Int64" Name="connectivity" format="appended" RangeMin="" RangeMax="" offset="608" />
+ <DataArray type="Int64" Name="offsets" format="appended" RangeMin="" RangeMax="" offset="672" />
+ <DataArray type="UInt8" Name="types" format="appended" RangeMin="" RangeMax="" offset="712" />
+ <DataArray type="Int64" Name="faces" format="appended" RangeMin="" RangeMax="" offset="748" />
+ <DataArray type="Int64" Name="faceoffsets" format="appended" RangeMin="" RangeMax="" offset="788" />
+ </Cells>
+ </Piece>
+ </UnstructuredGrid>
+ <AppendedData encoding="base64">
+ _AQAAAACAAADAAAAAOgAAAA==eJxjYMAO4vtPsM8s9rDHIc2QtJhxD6tQyn4YPxGqHl0cHcRA1cWimR+DxoeZAxOPQzMfJg4ATG4mZA==AQAAAACAAACAAQAAngAAAA==eJzT+/9++THv5fvrNOfqOzy/uF8Dyhed+9DQ91HEHgY0YAKVb4Kqt4TynS33B766VG6Drt4IKt8IVQ/Tz35Sp+7g7AAM9QlQ+Raoeisof7tYUOWDy9kY7rGByjdD1TtA+ZdCzy7NqLbDMF8OTb0MlJ/p7L/FsToFw3yY+2vQwueetxHL4Wh7DPUCaOEpC/NPQ7b6XDcrDPcAAJHIkuQ=AQAAAACAAACAAQAAhQAAAA==eJxTbTjBPrPYwz5mMeMeVqGU/epQvp+aTont7ae7GdCAHlQ+GapeB8rfLaMonpfCYoOu3hQqnwZVbwTlW83ccOFrznFrdPUGUPlUqHoY3weHe0xwqHfCYb4FVD4Dqt4cynfBYb4SVD4Kql4eyk8wcD/RKr0SZ/gkQdXD+Co43AMAF1loEQ==AQAAAACAAADAAAAAHAAAAA==eJxjYMAHPtjjlcaQh/GJ1YdLPy51mDQAp2EONQ==AQAAAACAAABAAAAAHgAAAA==eJxjYIAARijNDKWZoDQLlGaF0uxQmg1KAwAC8AAdAQAAAACAAAAIAAAACwAAAA==eJzjYIAAAABIAAk=AQAAAACAAAABAAAACQAAAA==eJzjAQAADQANAQAAAACAAAAIAAAACwAAAA==eJxjYIAAAAAIAAE=AQAAAACAAAAIAAAACwAAAA==eJxjZIAAAAAQAAI=
+ </AppendedData>
+</VTKFile>
diff --git a/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_101_t_5_100000_0.vtu b/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_101_t_5_100000_0.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..a0d73f72d2024becb7f290ac53b150c9727fce31
--- /dev/null
+++ b/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_101_t_5_100000_0.vtu
@@ -0,0 +1,60 @@
+<?xml version="1.0"?>
+<VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+ <UnstructuredGrid>
+ <Piece NumberOfPoints="8" NumberOfCells="1">
+ <PointData>
+ <DataArray type="Float64" Name="displacement" NumberOfComponents="3" format="binary" RangeMin="0" RangeMax="0.0058160307858">
+ AQAAAACAAADAAAAAMwAAAA==eJxjYMAOMqzUmCaZJtrjkGYoEFnn/rCqZD+6enRxXOaim4/Oh5mDrh4mngnlAwAVfyGm
+ </DataArray>
+ <DataArray type="Float64" Name="epsilon_xx" format="binary" RangeMin="0.002100738832" RangeMax="0.002100738832">
+ AQAAAACAAABAAAAAIQAAAA==eJxbVjtt0kTTRPslUHoZlF4FpVdA6dVQeg2aOgDTfR2Y
+ </DataArray>
+ <DataArray type="Float64" Name="epsilon_xy" format="binary" RangeMin="0" RangeMax="0">
+ AQAAAACAAABAAAAADAAAAA==eJxjYKAMAAAAQAAB
+ </DataArray>
+ <DataArray type="Float64" Name="epsilon_yy" format="binary" RangeMin="-0.005" RangeMax="-0.005">
+ AQAAAACAAABAAAAAHgAAAA==eJzLFVnn/rCqZH8hlC6A0llo4vlo/CIoDQAGLCA0
+ </DataArray>
+ <DataArray type="Float64" Name="epsilon_zz" format="binary" RangeMin="0.002100738832" RangeMax="0.002100738832">
+ AQAAAACAAABAAAAAHgAAAA==eJxbXTtt0kTTRPtlUHoFlF6Lxl8NpVeh0QDWBR2m
+ </DataArray>
+ <DataArray type="Float64" Name="sigma_xx" format="binary" RangeMin="-2.8228291448e-07" RangeMax="-2.8228291381e-07">
+ AQAAAACAAABAAAAAMwAAAA==eJwrk/iQNPXjpH0F9fVg+ua9S2Ba5u0SMK3vchFMn6k4BKalhOPAtMZ7mWQQDQDitSXs
+ </DataArray>
+ <DataArray type="Float64" Name="sigma_xy" format="binary" RangeMin="-9.7424738173e-18" RangeMax="6.1554594212e-17">
+ AQAAAACAAABAAAAASwAAAA==eJwBQAC//4qDstVptSc8rxihBPF2Zrx/Pfl8s4orPBL2dzf2hSC8vfvBv+O8Y7xs7ghp7b2RPFMvJVdECkG8B6FAKMpTRrwx3B+d
+ </DataArray>
+ <DataArray type="Float64" Name="sigma_yy" format="binary" RangeMin="-0.22776609819" RangeMax="-0.22776609819">
+ AQAAAACAAABAAAAAIwAAAA==eJy7aFnQXKB+dv9RKH0VSl+H0neg9EUovQ9K34bSACqsIQE=
+ </DataArray>
+ <DataArray type="Float64" Name="sigma_zz" format="binary" RangeMin="-2.8228291437e-07" RangeMax="-2.8228291366e-07">
+ AQAAAACAAABAAAAAMgAAAA==eJxzET6SNPXjpH1MtkFgWrB4GZg+vu4imA53+QumuY9OA9NdhkZget/692AaAHrAJSQ=
+ </DataArray>
+ </PointData>
+ <CellData>
+ </CellData>
+ <Points>
+ <DataArray type="Float64" Name="Points" NumberOfComponents="3" format="binary" RangeMin="0" RangeMax="1.7320508076">
+ AQAAAACAAADAAAAAHAAAAA==eJxjYMAHPtjjlcaQh/GJ1YdLPy51mDQAp2EONQ==
+ </DataArray>
+ </Points>
+ <Cells>
+ <DataArray type="Int64" Name="connectivity" format="binary" RangeMin="0" RangeMax="7">
+ AQAAAACAAABAAAAAHgAAAA==eJxjYIAARijNDKWZoDQLlGaF0uxQmg1KAwAC8AAd
+ </DataArray>
+ <DataArray type="Int64" Name="offsets" format="binary" RangeMin="8" RangeMax="8">
+ AQAAAACAAAAIAAAACwAAAA==eJzjYIAAAABIAAk=
+ </DataArray>
+ <DataArray type="UInt8" Name="types" format="binary" RangeMin="12" RangeMax="12">
+ AQAAAACAAAABAAAACQAAAA==eJzjAQAADQAN
+ </DataArray>
+ <DataArray type="Int64" Name="faces" format="binary" RangeMin="0" RangeMax="0">
+ AQAAAACAAAAIAAAACwAAAA==eJxjYIAAAAAIAAE=
+ </DataArray>
+ <DataArray type="Int64" Name="faceoffsets" format="binary" RangeMin="1" RangeMax="1">
+ AQAAAACAAAAIAAAACwAAAA==eJxjZIAAAAAQAAI=
+ </DataArray>
+ </Cells>
+ </Piece>
+ </UnstructuredGrid>
+</VTKFile>
diff --git a/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_203_t_5_100000_0.vtu b/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_203_t_5_100000_0.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..9901c70ccef11123f5b911b0004cfffdddc6f9a7
--- /dev/null
+++ b/Tests/Data/Mechanics/Ehlers/cube_1e0_ts_203_t_5_100000_0.vtu
@@ -0,0 +1,27 @@
+<?xml version="1.0"?>
+<VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+ <UnstructuredGrid>
+ <Piece NumberOfPoints="8" NumberOfCells="1" >
+ <PointData>
+ <DataArray type="Float64" Name="displacement" NumberOfComponents="3" format="appended" RangeMin="0" RangeMax="0.0057046735735" offset="0" />
+ <DataArray type="Float64" Name="sigma" NumberOfComponents="6" format="appended" RangeMin="0.25344987942" RangeMax="0.25344987942" offset="100" />
+ <DataArray type="Float64" Name="epsilon" NumberOfComponents="6" format="appended" RangeMin="0.0057046735735" RangeMax="0.0057046735735" offset="344" />
+ </PointData>
+ <CellData>
+ </CellData>
+ <Points>
+ <DataArray type="Float64" Name="Points" NumberOfComponents="3" format="appended" RangeMin="0" RangeMax="1.7320508076" offset="580" />
+ </Points>
+ <Cells>
+ <DataArray type="Int64" Name="connectivity" format="appended" RangeMin="" RangeMax="" offset="644" />
+ <DataArray type="Int64" Name="offsets" format="appended" RangeMin="" RangeMax="" offset="708" />
+ <DataArray type="UInt8" Name="types" format="appended" RangeMin="" RangeMax="" offset="748" />
+ <DataArray type="Int64" Name="faces" format="appended" RangeMin="" RangeMax="" offset="784" />
+ <DataArray type="Int64" Name="faceoffsets" format="appended" RangeMin="" RangeMax="" offset="824" />
+ </Cells>
+ </Piece>
+ </UnstructuredGrid>
+ <AppendedData encoding="base64">
+ _AQAAAACAAADAAAAAOQAAAA==eJxjYMAOfv3TObL0Yrw9DmmGapF17g+rSvbD+H+h6tHFcZn7F83872h8mDk/0NTDxH9C+QANeTgsAQAAAACAAACAAQAApQAAAA==eJxTD97g/rBqyn6V6/ETpspd2P8YyvcI/fja+1WeDQMaaAqByJtA1TNB+SHf0yusb9fvQVd/D2qeNlT9TCi/pzxnBmNZAoZ6F6h51lD1u6H88tDapKrz5RjuCYHKm0LV20D5wjcv/bmd34xh/pNgVPdvgvIFtepYdbsnYaivQvNvA5Q/N7a38aHqRAz3fIaapwdVD7PvtNRRzvaVKzDMBwAvUoqKAQAAAACAAACAAQAAnQAAAA==eJw78UznyNKL8fblIuvcH1aV7D8G5Z/4VyR8VuGpNQMauAKVr4eqvwDlz7h5ufuQCpMNuvqbUPk6qPrrUH5Nmr8+1+Qfu9HVX0JTD+N7q+mU2N4WxDD/BlS+Aaoe5r61PhEvqrYx70FXfwvN/TD36QmL7Zr3VgFD/RGofBFU/X4oXw2sXgzDPddg/kNz/4fpszPYVhpgmA8AlHyJZA==AQAAAACAAADAAAAAHAAAAA==eJxjYMAHPtjjlcaQh/GJ1YdLPy51mDQAp2EONQ==AQAAAACAAABAAAAAHgAAAA==eJxjYIAARijNDKWZoDQLlGaF0uxQmg1KAwAC8AAdAQAAAACAAAAIAAAACwAAAA==eJzjYIAAAABIAAk=AQAAAACAAAABAAAACQAAAA==eJzjAQAADQANAQAAAACAAAAIAAAACwAAAA==eJxjYIAAAAAIAAE=AQAAAACAAAAIAAAACwAAAA==eJxjZIAAAAAQAAI=
+ </AppendedData>
+</VTKFile>
diff --git a/Tests/Data/Mechanics/Linear/cube_1e0_SNES.prj b/Tests/Data/Mechanics/Linear/cube_1e0_SNES.prj
new file mode 100644
index 0000000000000000000000000000000000000000..dea66c1eb8a7e07c9c27c1685d77cb0b6b9b2339
--- /dev/null
+++ b/Tests/Data/Mechanics/Linear/cube_1e0_SNES.prj
@@ -0,0 +1,191 @@
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<OpenGeoSysProject>
+ <mesh>cube_1x1x1_hex_1e0.vtu</mesh>
+ <geometry>cube_1x1x1.gml</geometry>
+ <processes>
+ <process>
+ <name>SD</name>
+ <type>SMALL_DEFORMATION</type>
+ <integration_order>2</integration_order>
+ <constitutive_relation>
+ <type>LinearElasticIsotropic</type>
+ <youngs_modulus>E</youngs_modulus>
+ <poissons_ratio>nu</poissons_ratio>
+ </constitutive_relation>
+ <solid_density>rho_sr</solid_density>
+ <specific_body_force>0 0 0</specific_body_force>
+ <process_variables>
+ <process_variable>displacement</process_variable>
+ </process_variables>
+ <secondary_variables>
+ <secondary_variable internal_name="sigma" output_name="sigma"/>
+ <secondary_variable internal_name="epsilon" output_name="epsilon"/>
+ </secondary_variables>
+ </process>
+ </processes>
+ <time_loop>
+ <processes>
+ <process ref="SD">
+ <nonlinear_solver>petsc_snes</nonlinear_solver>
+ <convergence_criterion>
+ <type>DeltaX</type>
+ <norm_type>NORM2</norm_type>
+ <abstol>1e-15</abstol>
+ </convergence_criterion>
+ <time_discretization>
+ <type>BackwardEuler</type>
+ </time_discretization>
+ <time_stepping>
+ <type>FixedTimeStepping</type>
+ <t_initial>0</t_initial>
+ <t_end>1</t_end>
+ <timesteps>
+ <pair>
+ <repeat>4</repeat>
+ <delta_t>0.25</delta_t>
+ </pair>
+ </timesteps>
+ </time_stepping>
+ </process>
+ </processes>
+ <output>
+ <type>VTK</type>
+ <prefix>cube_1e0</prefix>
+ <timesteps>
+ <pair>
+ <repeat>1</repeat>
+ <each_steps>10000000</each_steps>
+ </pair>
+ </timesteps>
+ <variables>
+ <variable>displacement</variable>
+ <variable>sigma</variable>
+ <variable>epsilon</variable>
+ </variables>
+ <suffix>_ts_{:timestep}_t_{:time}</suffix>
+ </output>
+ </time_loop>
+ <parameters>
+ <parameter>
+ <name>E</name>
+ <type>Constant</type>
+ <value>1</value>
+ </parameter>
+ <parameter>
+ <name>nu</name>
+ <type>Constant</type>
+ <value>.3</value>
+ </parameter>
+ <parameter>
+ <name>rho_sr</name>
+ <type>Constant</type>
+ <value>1</value>
+ </parameter>
+ <parameter>
+ <name>displacement0</name>
+ <type>Constant</type>
+ <values>0 0 0</values>
+ </parameter>
+ <parameter>
+ <name>Dirichlet_left</name>
+ <type>Constant</type>
+ <value>0.</value>
+ </parameter>
+ <parameter>
+ <name>Dirichlet_bottom</name>
+ <type>Constant</type>
+ <value>0.</value>
+ </parameter>
+ <parameter>
+ <name>Dirichlet_front</name>
+ <type>Constant</type>
+ <value>0.</value>
+ </parameter>
+ <parameter>
+ <name>Neumann_force_top</name>
+ <type>Constant</type>
+ <value>0.01</value>
+ </parameter>
+ </parameters>
+ <process_variables>
+ <process_variable>
+ <name>displacement</name>
+ <components>3</components>
+ <order>1</order>
+ <initial_condition>displacement0</initial_condition>
+ <boundary_conditions>
+ <!-- fixed boundaries -->
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>left</geometry>
+ <type>Dirichlet</type>
+ <component>0</component>
+ <parameter>Dirichlet_left</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>front</geometry>
+ <type>Dirichlet</type>
+ <component>1</component>
+ <parameter>Dirichlet_front</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>bottom</geometry>
+ <type>Dirichlet</type>
+ <component>2</component>
+ <parameter>Dirichlet_bottom</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>cube_1x1x1_geometry</geometrical_set>
+ <geometry>top</geometry>
+ <type>Neumann</type>
+ <component>2</component>
+ <parameter>Neumann_force_top</parameter>
+ </boundary_condition>
+ </boundary_conditions>
+ </process_variable>
+ </process_variables>
+ <nonlinear_solvers>
+ <nonlinear_solver>
+ <name>petsc_snes</name>
+ <type>PETScSNES</type>
+ <max_iter>50</max_iter>
+ <linear_solver>general_linear_solver</linear_solver>
+ </nonlinear_solver>
+ </nonlinear_solvers>
+ <linear_solvers>
+ <linear_solver>
+ <name>general_linear_solver</name>
+ <petsc>
+ <parameters>-snes_type newtonls -ksp_type cg -pc_type bjacobi -ksp_rtol 1e-16 -ksp_max_it 10000</parameters>
+ </petsc>
+ </linear_solver>
+ </linear_solvers>
+ <test_definition>
+ <vtkdiff>
+ <file>cube_1e0_ts_4_t_1_000000.vtu</file>
+ <field>displacement</field>
+ <absolute_tolerance>1e-14</absolute_tolerance>
+ <relative_tolerance>1e-15</relative_tolerance>
+ </vtkdiff>
+ <vtkdiff>
+ <file>cube_1e0_ts_4_t_1_000000.vtu</file>
+ <field>NodalForces</field>
+ <absolute_tolerance>1e-14</absolute_tolerance>
+ <relative_tolerance>1e-15</relative_tolerance>
+ </vtkdiff>
+ <vtkdiff>
+ <file>cube_1e0_ts_4_t_1_000000.vtu</file>
+ <field>sigma</field>
+ <absolute_tolerance>1e-14</absolute_tolerance>
+ <relative_tolerance>1e-15</relative_tolerance>
+ </vtkdiff>
+ <vtkdiff>
+ <file>cube_1e0_ts_4_t_1_000000.vtu</file>
+ <field>epsilon</field>
+ <absolute_tolerance>1e-14</absolute_tolerance>
+ <relative_tolerance>1e-15</relative_tolerance>
+ </vtkdiff>
+ </test_definition>
+</OpenGeoSysProject>
diff --git a/Tests/Data/Mechanics/Linear/cube_1e0_ts_4_t_1_000000_0.vtu b/Tests/Data/Mechanics/Linear/cube_1e0_ts_4_t_1_000000_0.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..6b7576d86b6e86a487e99f8011921784689d2982
--- /dev/null
+++ b/Tests/Data/Mechanics/Linear/cube_1e0_ts_4_t_1_000000_0.vtu
@@ -0,0 +1,26 @@
+<?xml version="1.0"?>
+<VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+ <UnstructuredGrid>
+ <Piece NumberOfPoints="8" NumberOfCells="1" >
+ <PointData>
+ <DataArray type="Float64" Name="NodalForces" NumberOfComponents="3" format="appended" RangeMin="0.0025" RangeMax="0.0025" offset="0" />
+ <DataArray type="Float64" Name="displacement" NumberOfComponents="3" format="appended" RangeMin="0" RangeMax="0.010862780491" offset="252" />
+ <DataArray type="Float64" Name="sigma" NumberOfComponents="6" format="appended" RangeMin="0.01" RangeMax="0.01" offset="356" />
+ <DataArray type="Float64" Name="epsilon" NumberOfComponents="6" format="appended" RangeMin="0.010862780491" RangeMax="0.010862780491" offset="712" />
+ </PointData>
+ <CellData>
+ </CellData>
+ <Points>
+ <DataArray type="Float64" Name="Points" NumberOfComponents="3" format="appended" RangeMin="0" RangeMax="1.7320508076" offset="1116" />
+ </Points>
+ <Cells>
+ <DataArray type="Int64" Name="connectivity" format="appended" RangeMin="" RangeMax="" offset="1180" />
+ <DataArray type="Int64" Name="offsets" format="appended" RangeMin="" RangeMax="" offset="1244" />
+ <DataArray type="UInt8" Name="types" format="appended" RangeMin="" RangeMax="" offset="1284" />
+ </Cells>
+ </Piece>
+ </UnstructuredGrid>
+ <AppendedData encoding="base64">
+ _AQAAAACAAADAAAAAqgAAAA==eJz7nm+ykXnSR2sl1xezZG4x21SLrHN/WJWy/8HDz74/TXZa74xJvrfe7PXuKqj4K+H7D5tW/91tq5r9bkX5C2uY+udLglOmHfq4W2r1hs/7Zf/Cxb/s1mFXOXh3t1XChI7chw9310DE7bX/TegQyXq+e6f4WhElxXPWUPPty15aST45wmiT/C2uZHU96x6Y+InTleqLTjy33jRfxL3H7fNuqPn2AGVnY24=AQAAAACAAADAAAAAOgAAAA==eJxjYMAOftZl7SmZnLEfhzTDbzT5H1A+IX01IuvcH1a12KOrq4KKo9tfCRX/C+X/gtK1UHEAsJI05w==AQAAAACAAACAAQAA+QAAAA==eJy79mtf+IRYa5uJQRksbza52lSJrHN/WNVin/X5zdaP6hd2M6ABh9XR8w0X++6RKnusunWdzZ5yqPoEhqsOTwI2WqOrd3PlenbG1HnP9C37D8oLB+ypgapf1jB5z4+dKjbo6huemRrumhJko3bk+o8tDf42TVD1WjcXTfSUk8ZQHxPFxbDZx9/Gkivy0kSWAJsWqPqS7Db7M2IcGOqNZGUnTP3otGdP9PmMVg2XPXVQ9fMh7tmDrn6JmHh98OeAPcVK7duCrgTuyYGqf7r5qF2OnRaG+hk627mmS9jbqPE4G91ca27TAFXvuIJx7QkFHgz3AADIRHTbAQAAAACAAACAAQAAGwEAAA==eJz7Vpe1p2Ryxv7vULpSZJ37w6oW+weLfC13MVzdnfFpmh3nYsU939gnH6ydcGH3L6g6GF0OVf9B0iPkUNM2axmTK1wqR//sXutlE35S5ps1Qz1EHSOUroGqX9rbE334o5ZNRuiSxydlD+5+5mGS+fyi7J5/UHP/QOkmqPovN1fOq1mgaBOxq7TuyENJGxexWQaZzkJ7fkPV/UNT76k6NehaAL+N39UN99+oWuxRuWibe/GDx56/UHVMUPfUQdXPgbhnz8oFZ/V/1rvucWRliVJ/52TzEar+DZTOg6p/v8W4/yef4Z69by6rWR9ytTkjFK4U89gUbj7MPQ1Q9T/cSgqaPIRsJKTaa46quts07Pdwv/vinTUApF/FlQ==AQAAAACAAADAAAAAHAAAAA==eJxjYMAHPtjjlcaQh/GJ1YdLPy51mDQAp2EONQ==AQAAAACAAABAAAAAHgAAAA==eJxjYIAARijNDKWZoDQLlGaF0uxQmg1KAwAC8AAdAQAAAACAAAAIAAAACwAAAA==eJzjYIAAAABIAAk=AQAAAACAAAABAAAACQAAAA==eJzjAQAADQAN
+ </AppendedData>
+</VTKFile>
diff --git a/Tests/Data/Mechanics/Linear/square_1e0_SNES.prj b/Tests/Data/Mechanics/Linear/square_1e0_SNES.prj
new file mode 100644
index 0000000000000000000000000000000000000000..73a2ba31902dbda020da2287e0c9054c050d3621
--- /dev/null
+++ b/Tests/Data/Mechanics/Linear/square_1e0_SNES.prj
@@ -0,0 +1,159 @@
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<OpenGeoSysProject>
+ <mesh>square_1x1_quad_1e0.vtu</mesh>
+ <geometry>square_1x1.gml</geometry>
+ <processes>
+ <process>
+ <name>SD</name>
+ <type>SMALL_DEFORMATION</type>
+ <integration_order>2</integration_order>
+ <constitutive_relation>
+ <type>LinearElasticIsotropic</type>
+ <youngs_modulus>E</youngs_modulus>
+ <poissons_ratio>nu</poissons_ratio>
+ </constitutive_relation>
+ <solid_density>rho_sr</solid_density>
+ <specific_body_force>0 0</specific_body_force>
+ <process_variables>
+ <process_variable>displacement</process_variable>
+ </process_variables>
+ <secondary_variables>
+ <secondary_variable internal_name="sigma" output_name="sigma"/>
+ </secondary_variables>
+ </process>
+ </processes>
+ <time_loop>
+ <processes>
+ <process ref="SD">
+ <nonlinear_solver>petsc</nonlinear_solver>
+ <convergence_criterion>
+ <type>DeltaX</type>
+ <norm_type>NORM2</norm_type>
+ <abstol>1e-15</abstol>
+ </convergence_criterion>
+ <time_discretization>
+ <type>BackwardEuler</type>
+ </time_discretization>
+ <time_stepping>
+ <type>FixedTimeStepping</type>
+ <t_initial>0</t_initial>
+ <t_end>1</t_end>
+ <timesteps>
+ <pair>
+ <repeat>4</repeat>
+ <delta_t>0.25</delta_t>
+ </pair>
+ </timesteps>
+ </time_stepping>
+ </process>
+ </processes>
+ <output>
+ <type>VTK</type>
+ <prefix>square_1e0</prefix>
+ <timesteps>
+ <pair>
+ <repeat>1</repeat>
+ <each_steps>10000000</each_steps>
+ </pair>
+ </timesteps>
+ <variables>
+ <variable>displacement</variable>
+ <variable>sigma</variable>
+ </variables>
+ <suffix>_ts_{:timestep}_t_{:time}</suffix>
+ </output>
+ </time_loop>
+ <parameters>
+ <parameter>
+ <name>E</name>
+ <type>Constant</type>
+ <value>1</value>
+ </parameter>
+ <parameter>
+ <name>nu</name>
+ <type>Constant</type>
+ <value>.3</value>
+ </parameter>
+ <parameter>
+ <name>rho_sr</name>
+ <type>Constant</type>
+ <value>1</value>
+ </parameter>
+ <parameter>
+ <name>displacement0</name>
+ <type>Constant</type>
+ <values>0 0</values>
+ </parameter>
+ <parameter>
+ <name>dirichlet0</name>
+ <type>Constant</type>
+ <value>0</value>
+ </parameter>
+ <parameter>
+ <name>dirichlet1</name>
+ <type>Constant</type>
+ <value>0.05</value>
+ </parameter>
+ </parameters>
+ <process_variables>
+ <process_variable>
+ <name>displacement</name>
+ <components>2</components>
+ <order>1</order>
+ <initial_condition>displacement0</initial_condition>
+ <boundary_conditions>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>left</geometry>
+ <type>Dirichlet</type>
+ <component>0</component>
+ <parameter>dirichlet0</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>bottom</geometry>
+ <type>Dirichlet</type>
+ <component>1</component>
+ <parameter>dirichlet0</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>top</geometry>
+ <type>Dirichlet</type>
+ <component>1</component>
+ <parameter>dirichlet1</parameter>
+ </boundary_condition>
+ </boundary_conditions>
+ </process_variable>
+ </process_variables>
+ <nonlinear_solvers>
+ <nonlinear_solver>
+ <name>petsc</name>
+ <type>PETScSNES</type>
+ <max_iter>4</max_iter>
+ <linear_solver>general_linear_solver</linear_solver>
+ </nonlinear_solver>
+ </nonlinear_solvers>
+ <linear_solvers>
+ <linear_solver>
+ <name>general_linear_solver</name>
+ <petsc>
+ <parameters>-snes_type newtonls -ksp_type cg -pc_type bjacobi -ksp_rtol 1e-16 -ksp_max_it 10000</parameters>
+ </petsc>
+ </linear_solver>
+ </linear_solvers>
+ <test_definition>
+ <vtkdiff>
+ <file>square_1e0_ts_4_t_1_000000.vtu</file>
+ <field>displacement</field>
+ <absolute_tolerance>1e-16</absolute_tolerance>
+ <relative_tolerance>1e-16</relative_tolerance>
+ </vtkdiff>
+ <vtkdiff>
+ <file>square_1e0_ts_4_t_1_000000.vtu</file>
+ <field>sigma</field>
+ <absolute_tolerance>1e-16</absolute_tolerance>
+ <relative_tolerance>1e-16</relative_tolerance>
+ </vtkdiff>
+ </test_definition>
+</OpenGeoSysProject>
diff --git a/Tests/Data/Mechanics/Linear/square_1e0_ts_4_t_1_000000_0.vtu b/Tests/Data/Mechanics/Linear/square_1e0_ts_4_t_1_000000_0.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..56e701545f49b2d0a0e175fbe31d158d4f18f6cb
--- /dev/null
+++ b/Tests/Data/Mechanics/Linear/square_1e0_ts_4_t_1_000000_0.vtu
@@ -0,0 +1,39 @@
+<?xml version="1.0"?>
+<VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian" header_type="UInt32" compressor="vtkZLibDataCompressor">
+ <UnstructuredGrid>
+ <Piece NumberOfPoints="4" NumberOfCells="1">
+ <PointData>
+ <DataArray type="Float64" Name="NodalForces" NumberOfComponents="2" format="binary" RangeMin="0.027472527473" RangeMax="0.027472527473">
+ AQAAAACAAABAAAAALAAAAA==eJyTOvi/KXIpg43MIUUgmrNfCsLfA+Mvnvoo9SS/PEzeHsqHydsDAKCfG/U=
+ </DataArray>
+ <DataArray type="Float64" Name="displacement" NumberOfComponents="2" format="binary" RangeMin="0" RangeMax="0.054398379328">
+ AQAAAACAAABAAAAAIAAAAA==eJxjYEAFYvEfReM/Tt2PJswwayYIrLSHycP4AFfTET0=
+ </DataArray>
+ <DataArray type="Float64" Name="sigma" NumberOfComponents="4" format="binary" RangeMin="0.057364321478" RangeMax="0.057364321478">
+ AQAAAACAAACAAAAAQQAAAA==eJzjXHn06P0rMjZihxRlDimusefleyjA93CCPQMUCEDlRaDyPGjy0UuVWIufWe0RwiEfBZWXgcoLoskDAIPGJjc=
+ </DataArray>
+ </PointData>
+ <CellData>
+ <DataArray type="Int32" Name="MaterialIDs" format="binary" RangeMin="0" RangeMax="0">
+ AQAAAACAAAAEAAAADAAAAA==eJxjYGBgAAAABAAB
+ </DataArray>
+ </CellData>
+ <Points>
+ <DataArray type="Float64" Name="Points" NumberOfComponents="3" format="binary" RangeMin="0" RangeMax="1.4142135624">
+ AQAAAACAAABgAAAAFQAAAA==eJxjYMAHPtjjlcaQh/ER4gCW5AS9
+ </DataArray>
+ </Points>
+ <Cells>
+ <DataArray type="Int64" Name="connectivity" format="binary" RangeMin="0" RangeMax="3">
+ AQAAAACAAAAgAAAAEwAAAA==eJxjYIAARijNDKWZoDQAAHgABw==
+ </DataArray>
+ <DataArray type="Int64" Name="offsets" format="binary" RangeMin="4" RangeMax="4">
+ AQAAAACAAAAIAAAACwAAAA==eJxjYYAAAAAoAAU=
+ </DataArray>
+ <DataArray type="UInt8" Name="types" format="binary" RangeMin="9" RangeMax="9">
+ AQAAAACAAAABAAAACQAAAA==eJzjBAAACgAK
+ </DataArray>
+ </Cells>
+ </Piece>
+ </UnstructuredGrid>
+</VTKFile>