fond
Model Checking Contest 2020
10th edition, Paris, France, June 23, 2020
Execution of r227-oct2-159033546000003
Last Updated
Jun 28, 2020

About the Execution of ITS-Tools for SmartHome-PT-01

Execution Summary
Max Memory
Used (MB)
Time wait (ms) CPU Usage (ms) I/O Wait (ms) Computed Result Execution
Status
15729.500 4076.00 10414.00 60.60 FFTFFFFFFTTFFTTF normal

Execution Chart

We display below the execution chart for this examination (boot time has been removed).

Trace from the execution

Formatting '/data/fko/mcc2020-input.r227-oct2-159033546000003.qcow2', fmt=qcow2 size=4294967296 backing_file=/data/fko/mcc2020-input.qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
Waiting for the VM to be ready (probing ssh)
...........................................................................................................................................................................................................................................................................................................
=====================================================================
Generated by BenchKit 2-4028
Executing tool itstools
Input is SmartHome-PT-01, examination is CTLCardinality
Time confinement is 3600 seconds
Memory confinement is 16384 MBytes
Number of cores is 4
Run identifier is r227-oct2-159033546000003
=====================================================================

--------------------
preparation of the directory to be used:
/home/mcc/execution
total 196K
-rw-r--r-- 1 mcc users 3.3K May 14 03:41 CTLCardinality.txt
-rw-r--r-- 1 mcc users 19K May 14 03:41 CTLCardinality.xml
-rw-r--r-- 1 mcc users 2.3K May 13 21:16 CTLFireability.txt
-rw-r--r-- 1 mcc users 15K May 13 21:16 CTLFireability.xml
-rw-r--r-- 1 mcc users 3.5K May 14 10:05 LTLCardinality.txt
-rw-r--r-- 1 mcc users 28K May 14 10:05 LTLCardinality.xml
-rw-r--r-- 1 mcc users 1.8K May 14 10:05 LTLFireability.txt
-rw-r--r-- 1 mcc users 15K May 14 10:05 LTLFireability.xml
-rw-r--r-- 1 mcc users 1 May 12 20:42 NewModel
-rw-r--r-- 1 mcc users 3.2K May 13 14:58 ReachabilityCardinality.txt
-rw-r--r-- 1 mcc users 17K May 13 14:58 ReachabilityCardinality.xml
-rw-r--r-- 1 mcc users 2.8K May 13 10:15 ReachabilityFireability.txt
-rw-r--r-- 1 mcc users 19K May 13 10:15 ReachabilityFireability.xml
-rw-r--r-- 1 mcc users 1.6K May 13 16:53 UpperBounds.txt
-rw-r--r-- 1 mcc users 3.6K May 13 16:53 UpperBounds.xml
-rw-r--r-- 1 mcc users 6 May 12 20:42 equiv_col
-rw-r--r-- 1 mcc users 3 May 12 20:42 instance
-rw-r--r-- 1 mcc users 6 May 12 20:42 iscolored
-rw-r--r-- 1 mcc users 25K May 12 20:42 model.pnml

--------------------
content from stdout:

=== Data for post analysis generated by BenchKit (invocation template)

The expected result is a vector of booleans
BOOL_VECTOR

here is the order used to build the result vector(from text file)
FORMULA_NAME SmartHome-PT-01-CTLCardinality-00
FORMULA_NAME SmartHome-PT-01-CTLCardinality-01
FORMULA_NAME SmartHome-PT-01-CTLCardinality-02
FORMULA_NAME SmartHome-PT-01-CTLCardinality-03
FORMULA_NAME SmartHome-PT-01-CTLCardinality-04
FORMULA_NAME SmartHome-PT-01-CTLCardinality-05
FORMULA_NAME SmartHome-PT-01-CTLCardinality-06
FORMULA_NAME SmartHome-PT-01-CTLCardinality-07
FORMULA_NAME SmartHome-PT-01-CTLCardinality-08
FORMULA_NAME SmartHome-PT-01-CTLCardinality-09
FORMULA_NAME SmartHome-PT-01-CTLCardinality-10
FORMULA_NAME SmartHome-PT-01-CTLCardinality-11
FORMULA_NAME SmartHome-PT-01-CTLCardinality-12
FORMULA_NAME SmartHome-PT-01-CTLCardinality-13
FORMULA_NAME SmartHome-PT-01-CTLCardinality-14
FORMULA_NAME SmartHome-PT-01-CTLCardinality-15

=== Now, execution of the tool begins

BK_START 1590483636637

[2020-05-26 09:00:38] [INFO ] Running its-tools with arguments : [-pnfolder, /home/mcc/execution, -examination, CTLCardinality, -z3path, /home/mcc/BenchKit//z3/bin/z3, -yices2path, /home/mcc/BenchKit//yices/bin/yices, -its, -ltsminpath, /home/mcc/BenchKit//lts_install_dir/, -greatspnpath, /home/mcc/BenchKit//greatspn/, -order, META, -manyOrder, -smt, -timeout, 3600]
[2020-05-26 09:00:38] [INFO ] Parsing pnml file : /home/mcc/execution/model.pnml
[2020-05-26 09:00:38] [INFO ] Load time of PNML (sax parser for PT used): 35 ms
[2020-05-26 09:00:38] [INFO ] Transformed 38 places.
[2020-05-26 09:00:38] [INFO ] Transformed 113 transitions.
[2020-05-26 09:00:38] [INFO ] Found NUPN structural information;
[2020-05-26 09:00:38] [INFO ] Parsed PT model containing 38 places and 113 transitions in 71 ms.
Ensure Unique test removed 58 transitions
Reduce redundant transitions removed 58 transitions.
Parsed 16 properties from file /home/mcc/execution/CTLCardinality.xml in 16 ms.
Incomplete random walk after 100000 steps, including 0 resets, run finished after 162 ms. (steps per millisecond=617 ) properties seen :[0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0]
[2020-05-26 09:00:38] [INFO ] Flow matrix only has 34 transitions (discarded 21 similar events)
// Phase 1: matrix 34 rows 38 cols
[2020-05-26 09:00:38] [INFO ] Computed 15 place invariants in 2 ms
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using 14 positive place invariants in 16 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using 14 positive and 1 generalized place invariants in 2 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using state equation in 42 ms returned sat
[2020-05-26 09:00:38] [INFO ] Solution in real domain found non-integer solution.
[2020-05-26 09:00:38] [INFO ] [Nat]Absence check using 14 positive place invariants in 19 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Nat]Absence check using 14 positive and 1 generalized place invariants in 0 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:38] [INFO ] [Nat]Absence check using state equation in 14 ms returned unsat
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using 14 positive place invariants in 8 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using 14 positive and 1 generalized place invariants in 1 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using state equation in 104 ms returned sat
[2020-05-26 09:00:38] [INFO ] Solution in real domain found non-integer solution.
[2020-05-26 09:00:38] [INFO ] [Nat]Absence check using 14 positive place invariants in 9 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Nat]Absence check using 14 positive and 1 generalized place invariants in 2 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:38] [INFO ] [Nat]Absence check using state equation in 13 ms returned unsat
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using 14 positive place invariants in 13 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using 14 positive and 1 generalized place invariants in 1 ms returned sat
[2020-05-26 09:00:38] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:38] [INFO ] [Real]Absence check using state equation in 34 ms returned sat
[2020-05-26 09:00:38] [INFO ] Solution in real domain found non-integer solution.
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using 14 positive place invariants in 14 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using 14 positive and 1 generalized place invariants in 1 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using state equation in 40 ms returned sat
[2020-05-26 09:00:39] [INFO ] State equation strengthened by 21 read => feed constraints.
[2020-05-26 09:00:39] [INFO ] [Nat]Added 21 Read/Feed constraints in 15 ms returned sat
[2020-05-26 09:00:39] [INFO ] Computed and/alt/rep : 54/133/33 causal constraints in 7 ms.
[2020-05-26 09:00:39] [INFO ] Added : 32 causal constraints over 7 iterations in 128 ms. Result :sat
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using 14 positive place invariants in 78 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using 14 positive and 1 generalized place invariants in 1 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using state equation in 73 ms returned sat
[2020-05-26 09:00:39] [INFO ] Solution in real domain found non-integer solution.
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using 14 positive place invariants in 49 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using 14 positive and 1 generalized place invariants in 1 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using state equation in 25 ms returned unsat
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using 14 positive place invariants in 5 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using 14 positive and 1 generalized place invariants in 0 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using state equation in 11 ms returned sat
[2020-05-26 09:00:39] [INFO ] Solution in real domain found non-integer solution.
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using 14 positive place invariants in 15 ms returned unsat
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using 14 positive place invariants in 4 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using 14 positive and 1 generalized place invariants in 0 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:39] [INFO ] [Real]Absence check using state equation in 51 ms returned sat
[2020-05-26 09:00:39] [INFO ] Solution in real domain found non-integer solution.
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using 14 positive place invariants in 7 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using 14 positive and 1 generalized place invariants in 0 ms returned sat
[2020-05-26 09:00:39] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2020-05-26 09:00:39] [INFO ] [Nat]Absence check using state equation in 19 ms returned unsat
Successfully simplified 5 atomic propositions for a total of 5 simplifications.
[2020-05-26 09:00:39] [INFO ] Initial state reduction rules for CTL removed 13 formulas.
[2020-05-26 09:00:39] [INFO ] Flatten gal took : 54 ms
[2020-05-26 09:00:39] [INFO ] Initial state reduction rules for CTL removed 13 formulas.
[2020-05-26 09:00:39] [INFO ] Flatten gal took : 8 ms
FORMULA SmartHome-PT-01-CTLCardinality-15 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-14 TRUE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-13 TRUE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-12 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-11 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-08 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-07 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-06 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-05 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-04 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-02 TRUE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-01 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
FORMULA SmartHome-PT-01-CTLCardinality-00 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
[2020-05-26 09:00:39] [INFO ] Applying decomposition
[2020-05-26 09:00:39] [INFO ] Flatten gal took : 4 ms
Converted graph to binary with : CommandLine [args=[/home/mcc/BenchKit/itstools/plugins/fr.lip6.move.gal.louvain.binaries_1.0.0.202005100927/bin/convert-linux64, -i, /tmp/graph1391715705258925283.txt, -o, /tmp/graph1391715705258925283.bin, -w, /tmp/graph1391715705258925283.weights], workingDir=null]
Built communities with : CommandLine [args=[/home/mcc/BenchKit/itstools/plugins/fr.lip6.move.gal.louvain.binaries_1.0.0.202005100927/bin/louvain-linux64, /tmp/graph1391715705258925283.bin, -l, -1, -v, -w, /tmp/graph1391715705258925283.weights, -q, 0, -e, 0.001], workingDir=null]
[2020-05-26 09:00:40] [INFO ] Decomposing Gal with order
[2020-05-26 09:00:40] [INFO ] Rewriting arrays to variables to allow decomposition.
[2020-05-26 09:00:40] [INFO ] Removed a total of 22 redundant transitions.
[2020-05-26 09:00:40] [INFO ] Flatten gal took : 23 ms
[2020-05-26 09:00:40] [INFO ] Fuse similar labels procedure discarded/fused a total of 4 labels/synchronizations in 2 ms.
[2020-05-26 09:00:40] [INFO ] Time to serialize gal into /home/mcc/execution/CTLCardinality.pnml.gal : 1 ms
[2020-05-26 09:00:40] [INFO ] Time to serialize properties into /home/mcc/execution/CTLCardinality.ctl : 0 ms
Invoking ITS tools like this :CommandLine [args=[/home/mcc/BenchKit/itstools/plugins/fr.lip6.move.gal.itstools.binaries_1.0.0.202005100927/bin/its-ctl-linux64, --gc-threshold, 2000000, --quiet, -i, /home/mcc/execution/CTLCardinality.pnml.gal, -t, CGAL, -ctl, /home/mcc/execution/CTLCardinality.ctl], workingDir=/home/mcc/execution]

its-ctl command run as :

/home/mcc/BenchKit/itstools/plugins/fr.lip6.move.gal.itstools.binaries_1.0.0.202005100927/bin/its-ctl-linux64 --gc-threshold 2000000 --quiet -i /home/mcc/execution/CTLCardinality.pnml.gal -t CGAL -ctl /home/mcc/execution/CTLCardinality.ctl
No direction supplied, using forward translation only.
Parsed 3 CTL formulae.
built 18 ordering constraints for composite.
built 6 ordering constraints for composite.
built 8 ordering constraints for composite.
built 7 ordering constraints for composite.
built 6 ordering constraints for composite.
built 6 ordering constraints for composite.
built 6 ordering constraints for composite.
Model ,|S| ,Time ,Mem(kb) ,fin. SDD ,fin. DDD ,peak SDD ,peak DDD ,SDD Hom ,SDD cache peak ,DDD Hom ,DDD cachepeak ,SHom cache
reachable,43201,0.015224,4656,58,21,330,107,151,356,39,192,0


Converting to forward existential form...Done !
original formula: EF(AX(FALSE))
=> equivalent forward existential formula: [(FwdU(Init,TRUE) * !(EX(!(FALSE))))] != FALSE
Reverse transition relation is NOT exact ! Due to transitions t77, i2.u4.t75, i7.t79, Intersection with reachable at each step enabled. (destroyed/reverse/intersect/total) :0/50/3/53
(forward)formula 0,0,0.020489,4656,1,0,673,107,491,774,153,192,1902
FORMULA SmartHome-PT-01-CTLCardinality-03 FALSE TECHNIQUES DECISION_DIAGRAMS TOPOLOGICAL USE_NUPN
Formula is FALSE !

***************************************

original formula: AG(EF((((i4.u9.p22==0)||(i1.u2.p6==1))&&((i5.u11.p28==0)||(i4.u10.p25==1)))))
=> equivalent forward existential formula: [(FwdU(Init,TRUE) * !(E(TRUE U (((i4.u9.p22==0)||(i1.u2.p6==1))&&((i5.u11.p28==0)||(i4.u10.p25==1))))))] = FALSE
(forward)formula 1,1,0.022666,5096,1,0,695,107,638,802,165,192,2321
FORMULA SmartHome-PT-01-CTLCardinality-09 TRUE TECHNIQUES DECISION_DIAGRAMS TOPOLOGICAL USE_NUPN
Formula is TRUE !

***************************************

original formula: EX(TRUE)
=> equivalent forward existential formula: [(EY(Init) * TRUE)] != FALSE
(forward)formula 2,1,0.022919,5096,1,0,695,107,652,810,165,192,2371
FORMULA SmartHome-PT-01-CTLCardinality-10 TRUE TECHNIQUES DECISION_DIAGRAMS TOPOLOGICAL USE_NUPN
Formula is TRUE !

***************************************


BK_STOP 1590483640713

--------------------
content from stderr:

+ export BINDIR=/home/mcc/BenchKit/
+ BINDIR=/home/mcc/BenchKit/
++ pwd
+ export MODEL=/home/mcc/execution
+ MODEL=/home/mcc/execution
+ [[ CTLCardinality = StateSpace ]]
+ /home/mcc/BenchKit//runeclipse.sh /home/mcc/execution CTLCardinality -its -ltsminpath /home/mcc/BenchKit//lts_install_dir/ -greatspnpath /home/mcc/BenchKit//greatspn/ -order META -manyOrder -smt -timeout 3600
+ ulimit -s 65536
+ [[ -z '' ]]
+ export LTSMIN_MEM_SIZE=8589934592
+ LTSMIN_MEM_SIZE=8589934592
+ /home/mcc/BenchKit//itstools/its-tools -data /home/mcc/execution/workspace -pnfolder /home/mcc/execution -examination CTLCardinality -z3path /home/mcc/BenchKit//z3/bin/z3 -yices2path /home/mcc/BenchKit//yices/bin/yices -its -ltsminpath /home/mcc/BenchKit//lts_install_dir/ -greatspnpath /home/mcc/BenchKit//greatspn/ -order META -manyOrder -smt -timeout 3600 -vmargs -Dosgi.locking=none -Declipse.stateSaveDelayInterval=-1 -Dosgi.configuration.area=/tmp/.eclipse -Xss128m -Xms40m -Xmx16000m -Dfile.encoding=UTF-8 -Dosgi.requiredJavaVersion=1.6

Sequence of Actions to be Executed by the VM

This is useful if one wants to reexecute the tool in the VM from the submitted image disk.

set -x
# this is for BenchKit: configuration of major elements for the test
export BK_INPUT="SmartHome-PT-01"
export BK_EXAMINATION="CTLCardinality"
export BK_TOOL="itstools"
export BK_RESULT_DIR="/tmp/BK_RESULTS/OUTPUTS"
export BK_TIME_CONFINEMENT="3600"
export BK_MEMORY_CONFINEMENT="16384"

# this is specific to your benchmark or test

export BIN_DIR="$HOME/BenchKit/bin"

# remove the execution directoty if it exists (to avoid increse of .vmdk images)
if [ -d execution ] ; then
rm -rf execution
fi

# this is for BenchKit: explicit launching of the test
echo "====================================================================="
echo " Generated by BenchKit 2-4028"
echo " Executing tool itstools"
echo " Input is SmartHome-PT-01, examination is CTLCardinality"
echo " Time confinement is $BK_TIME_CONFINEMENT seconds"
echo " Memory confinement is 16384 MBytes"
echo " Number of cores is 4"
echo " Run identifier is r227-oct2-159033546000003"
echo "====================================================================="
echo
echo "--------------------"
echo "preparation of the directory to be used:"

tar xzf /home/mcc/BenchKit/INPUTS/SmartHome-PT-01.tgz
mv SmartHome-PT-01 execution
cd execution
if [ "CTLCardinality" = "ReachabilityDeadlock" ] || [ "CTLCardinality" = "UpperBounds" ] || [ "CTLCardinality" = "QuasiLiveness" ] || [ "CTLCardinality" = "StableMarking" ] || [ "CTLCardinality" = "Liveness" ] || [ "CTLCardinality" = "OneSafe" ] || [ "CTLCardinality" = "StateSpace" ]; then
rm -f GenericPropertiesVerdict.xml
fi
pwd
ls -lh

echo
echo "--------------------"
echo "content from stdout:"
echo
echo "=== Data for post analysis generated by BenchKit (invocation template)"
echo
if [ "CTLCardinality" = "UpperBounds" ] ; then
echo "The expected result is a vector of positive values"
echo NUM_VECTOR
elif [ "CTLCardinality" != "StateSpace" ] ; then
echo "The expected result is a vector of booleans"
echo BOOL_VECTOR
else
echo "no data necessary for post analysis"
fi
echo
if [ -f "CTLCardinality.txt" ] ; then
echo "here is the order used to build the result vector(from text file)"
for x in $(grep Property CTLCardinality.txt | cut -d ' ' -f 2 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ -f "CTLCardinality.xml" ] ; then # for cunf (txt files deleted;-)
echo echo "here is the order used to build the result vector(from xml file)"
for x in $(grep '' CTLCardinality.xml | cut -d '>' -f 2 | cut -d '<' -f 1 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ "CTLCardinality" = "ReachabilityDeadlock" ] || [ "CTLCardinality" = "QuasiLiveness" ] || [ "CTLCardinality" = "StableMarking" ] || [ "CTLCardinality" = "Liveness" ] || [ "CTLCardinality" = "OneSafe" ] ; then
echo "FORMULA_NAME CTLCardinality"
fi
echo
echo "=== Now, execution of the tool begins"
echo
echo -n "BK_START "
date -u +%s%3N
echo
timeout -s 9 $BK_TIME_CONFINEMENT bash -c "/home/mcc/BenchKit/BenchKit_head.sh 2> STDERR ; echo ; echo -n \"BK_STOP \" ; date -u +%s%3N"
if [ $? -eq 137 ] ; then
echo
echo "BK_TIME_CONFINEMENT_REACHED"
fi
echo
echo "--------------------"
echo "content from stderr:"
echo
cat STDERR ;