fond
Model Checking Contest 2021
11th edition, Paris, France, June 23, 2021
Execution of r083-tall-162048875000110
Last Updated
Jun 28, 2021

About the Execution of ITS-Tools for Diffusion2D-PT-D20N010

Execution Summary
Max Memory
Used (MB)
Time wait (ms) CPU Usage (ms) I/O Wait (ms) Computed Result Execution
Status
472.155 13788.00 24574.00 73.70 FTTTFTFFTTTTTFFF normal

Execution Chart

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

Trace from the execution

Formatting '/data/fkordon/mcc2021-input.r083-tall-162048875000110.qcow2', fmt=qcow2 size=4294967296 backing_file='/data/fkordon/mcc2021-input.qcow2' encryption=off cluster_size=65536 lazy_refcounts=off
Waiting for the VM to be ready (probing ssh)
...................
=====================================================================
Generated by BenchKit 2-4028
Executing tool itstools
Input is Diffusion2D-PT-D20N010, examination is ReachabilityCardinality
Time confinement is 3600 seconds
Memory confinement is 16384 MBytes
Number of cores is 4
Run identifier is r083-tall-162048875000110
=====================================================================

--------------------
preparation of the directory to be used:
/home/mcc/execution
total 1.5M
-rw-r--r-- 1 mcc users 19K May 5 16:58 CTLCardinality.txt
-rw-r--r-- 1 mcc users 124K May 5 16:58 CTLCardinality.xml
-rw-r--r-- 1 mcc users 14K May 5 16:58 CTLFireability.txt
-rw-r--r-- 1 mcc users 83K May 5 16:58 CTLFireability.xml
-rw-r--r-- 1 mcc users 4.2K May 6 14:48 GenericPropertiesDefinition.xml
-rw-r--r-- 1 mcc users 6.3K May 6 14:48 GenericPropertiesVerdict.xml
-rw-r--r-- 1 mcc users 3.9K Mar 28 16:02 LTLCardinality.txt
-rw-r--r-- 1 mcc users 24K Mar 28 16:02 LTLCardinality.xml
-rw-r--r-- 1 mcc users 2.5K Mar 28 16:02 LTLFireability.txt
-rw-r--r-- 1 mcc users 19K Mar 28 16:02 LTLFireability.xml
-rw-r--r-- 1 mcc users 3.6K Mar 23 10:19 ReachabilityCardinality.txt
-rw-r--r-- 1 mcc users 16K Mar 23 10:19 ReachabilityCardinality.xml
-rw-r--r-- 1 mcc users 3.3K Mar 22 17:57 ReachabilityFireability.txt
-rw-r--r-- 1 mcc users 17K Mar 22 17:57 ReachabilityFireability.xml
-rw-r--r-- 1 mcc users 1.8K Mar 22 09:11 UpperBounds.txt
-rw-r--r-- 1 mcc users 3.8K Mar 22 09:11 UpperBounds.xml
-rw-r--r-- 1 mcc users 6 May 5 16:51 equiv_col
-rw-r--r-- 1 mcc users 8 May 5 16:51 instance
-rw-r--r-- 1 mcc users 6 May 5 16:51 iscolored
-rw-r--r-- 1 mcc users 1.2M May 5 16:51 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 Diffusion2D-PT-D20N010-ReachabilityCardinality-00
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-01
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-02
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-03
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-04
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-05
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-06
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-07
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-08
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-09
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-10
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-11
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-12
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-13
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-14
FORMULA_NAME Diffusion2D-PT-D20N010-ReachabilityCardinality-15

=== Now, execution of the tool begins

BK_START 1620542455186

Running Version 0
[2021-05-09 06:40:56] [INFO ] Running its-tools with arguments : [-pnfolder, /home/mcc/execution, -examination, ReachabilityCardinality, -spotpath, /home/mcc/BenchKit/bin//..//ltlfilt, -z3path, /home/mcc/BenchKit/bin//..//z3/bin/z3, -yices2path, /home/mcc/BenchKit/bin//..//yices/bin/yices, -its, -ltsmin, -greatspnpath, /home/mcc/BenchKit/bin//..//greatspn/, -order, META, -manyOrder, -smt, -timeout, 3600]
[2021-05-09 06:40:56] [INFO ] Parsing pnml file : /home/mcc/execution/model.pnml
[2021-05-09 06:40:56] [INFO ] Load time of PNML (sax parser for PT used): 127 ms
[2021-05-09 06:40:56] [INFO ] Transformed 400 places.
[2021-05-09 06:40:56] [INFO ] Transformed 2964 transitions.
[2021-05-09 06:40:56] [INFO ] Parsed PT model containing 400 places and 2964 transitions in 175 ms.
Parsed 16 properties from file /home/mcc/execution/ReachabilityCardinality.xml in 8 ms.
Working with output stream class java.io.PrintStream
Incomplete random walk after 10002 steps, including 2 resets, run finished after 36 ms. (steps per millisecond=277 ) properties (out of 16) seen :7
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-14 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-13 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-11 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-10 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-05 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-04 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-00 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 11 ms. (steps per millisecond=909 ) properties (out of 9) seen :0
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 15 ms. (steps per millisecond=666 ) properties (out of 9) seen :0
Incomplete Best-First random walk after 10000 steps, including 2 resets, run finished after 16 ms. (steps per millisecond=625 ) properties (out of 9) seen :0
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 10 ms. (steps per millisecond=1000 ) properties (out of 9) seen :0
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 11 ms. (steps per millisecond=909 ) properties (out of 9) seen :0
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 11 ms. (steps per millisecond=909 ) properties (out of 9) seen :0
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 11 ms. (steps per millisecond=909 ) properties (out of 9) seen :0
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 13 ms. (steps per millisecond=769 ) properties (out of 9) seen :0
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 10 ms. (steps per millisecond=1000 ) properties (out of 9) seen :0
Running SMT prover for 9 properties.
// Phase 1: matrix 2964 rows 400 cols
[2021-05-09 06:40:57] [INFO ] Computed 1 place invariants in 45 ms
[2021-05-09 06:40:57] [INFO ] [Real]Absence check using 1 positive place invariants in 6 ms returned sat
[2021-05-09 06:40:57] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:40:57] [INFO ] [Real]Absence check using state equation in 418 ms returned sat
[2021-05-09 06:40:58] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 213 ms.
Attempting to minimize the solution found.
Minimization took 11 ms.
[2021-05-09 06:40:58] [INFO ] [Real]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:40:58] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:40:58] [INFO ] [Real]Absence check using state equation in 427 ms returned sat
[2021-05-09 06:40:58] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 156 ms.
Attempting to minimize the solution found.
Minimization took 3 ms.
[2021-05-09 06:40:59] [INFO ] [Real]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:40:59] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:40:59] [INFO ] [Real]Absence check using state equation in 376 ms returned sat
[2021-05-09 06:40:59] [INFO ] Solution in real domain found non-integer solution.
[2021-05-09 06:40:59] [INFO ] [Nat]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:40:59] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2021-05-09 06:40:59] [INFO ] [Nat]Absence check using state equation in 372 ms returned sat
[2021-05-09 06:41:00] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 170 ms.
Attempting to minimize the solution found.
Minimization took 3 ms.
[2021-05-09 06:41:00] [INFO ] [Real]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:00] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:00] [INFO ] [Real]Absence check using state equation in 384 ms returned sat
[2021-05-09 06:41:00] [INFO ] Solution in real domain found non-integer solution.
[2021-05-09 06:41:00] [INFO ] [Nat]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:00] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:01] [INFO ] [Nat]Absence check using state equation in 390 ms returned sat
[2021-05-09 06:41:01] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 149 ms.
Attempting to minimize the solution found.
Minimization took 10 ms.
[2021-05-09 06:41:01] [INFO ] [Real]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:01] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:01] [INFO ] [Real]Absence check using state equation in 379 ms returned sat
[2021-05-09 06:41:01] [INFO ] Solution in real domain found non-integer solution.
[2021-05-09 06:41:01] [INFO ] [Nat]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:01] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:02] [INFO ] [Nat]Absence check using state equation in 365 ms returned sat
[2021-05-09 06:41:02] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 153 ms.
Attempting to minimize the solution found.
Minimization took 3 ms.
[2021-05-09 06:41:02] [INFO ] [Real]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:02] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:03] [INFO ] [Real]Absence check using state equation in 372 ms returned sat
[2021-05-09 06:41:03] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 140 ms.
Attempting to minimize the solution found.
Minimization took 3 ms.
[2021-05-09 06:41:03] [INFO ] [Real]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:03] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:03] [INFO ] [Real]Absence check using state equation in 398 ms returned sat
[2021-05-09 06:41:03] [INFO ] Solution in real domain found non-integer solution.
[2021-05-09 06:41:03] [INFO ] [Nat]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:03] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:04] [INFO ] [Nat]Absence check using state equation in 373 ms returned sat
[2021-05-09 06:41:04] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 133 ms.
Attempting to minimize the solution found.
Minimization took 3 ms.
[2021-05-09 06:41:04] [INFO ] [Real]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:04] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:04] [INFO ] [Real]Absence check using state equation in 401 ms returned sat
[2021-05-09 06:41:05] [INFO ] Solution in real domain found non-integer solution.
[2021-05-09 06:41:05] [INFO ] [Nat]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:05] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:05] [INFO ] [Nat]Absence check using state equation in 394 ms returned sat
[2021-05-09 06:41:05] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 148 ms.
Attempting to minimize the solution found.
Minimization took 3 ms.
[2021-05-09 06:41:05] [INFO ] [Real]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:05] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:06] [INFO ] [Real]Absence check using state equation in 375 ms returned sat
[2021-05-09 06:41:06] [INFO ] Solution in real domain found non-integer solution.
[2021-05-09 06:41:06] [INFO ] [Nat]Absence check using 1 positive place invariants in 4 ms returned sat
[2021-05-09 06:41:06] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2021-05-09 06:41:06] [INFO ] [Nat]Absence check using state equation in 381 ms returned sat
[2021-05-09 06:41:06] [INFO ] Computed and/alt/rep : 2956/22508/2956 causal constraints (skipped 0 transitions) in 133 ms.
Attempting to minimize the solution found.
Minimization took 3 ms.
Incomplete Parikh walk after 52900 steps, including 159 resets, run finished after 289 ms. (steps per millisecond=183 ) properties (out of 9) seen :2 could not realise parikh vector
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-06 FALSE TECHNIQUES TOPOLOGICAL PARIKH_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-01 TRUE TECHNIQUES TOPOLOGICAL PARIKH_WALK
Incomplete Parikh walk after 129400 steps, including 155 resets, run finished after 454 ms. (steps per millisecond=285 ) properties (out of 7) seen :5 could not realise parikh vector
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-15 FALSE TECHNIQUES TOPOLOGICAL PARIKH_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-09 TRUE TECHNIQUES TOPOLOGICAL PARIKH_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-07 FALSE TECHNIQUES TOPOLOGICAL PARIKH_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-03 TRUE TECHNIQUES TOPOLOGICAL PARIKH_WALK
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-02 TRUE TECHNIQUES TOPOLOGICAL PARIKH_WALK
Incomplete Parikh walk after 20200 steps, including 116 resets, run finished after 73 ms. (steps per millisecond=276 ) properties (out of 2) seen :0 could not realise parikh vector
Incomplete Parikh walk after 38500 steps, including 206 resets, run finished after 152 ms. (steps per millisecond=253 ) properties (out of 2) seen :0 could not realise parikh vector
Incomplete Parikh walk after 22100 steps, including 126 resets, run finished after 77 ms. (steps per millisecond=287 ) properties (out of 2) seen :0 could not realise parikh vector
Incomplete Parikh walk after 38200 steps, including 147 resets, run finished after 129 ms. (steps per millisecond=296 ) properties (out of 2) seen :1 could not realise parikh vector
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-08 TRUE TECHNIQUES TOPOLOGICAL PARIKH_WALK
Finished Parikh walk after 37277 steps, including 72 resets, run visited all 1 properties in 128 ms. (steps per millisecond=291 )
FORMULA Diffusion2D-PT-D20N010-ReachabilityCardinality-12 TRUE TECHNIQUES TOPOLOGICAL PARIKH_WALK
All properties solved without resorting to model-checking.

BK_STOP 1620542468974

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

+ export BINDIR=/home/mcc/BenchKit/bin//../
+ BINDIR=/home/mcc/BenchKit/bin//../
++ pwd
+ export MODEL=/home/mcc/execution
+ MODEL=/home/mcc/execution
+ [[ ReachabilityCardinality = StateSpace ]]
+ /home/mcc/BenchKit/bin//..//runeclipse.sh /home/mcc/execution ReachabilityCardinality -its -ltsmin -greatspnpath /home/mcc/BenchKit/bin//..//greatspn/ -order META -manyOrder -smt -timeout 3600
+ ulimit -s 65536
+ [[ -z '' ]]
+ export LTSMIN_MEM_SIZE=8589934592
+ LTSMIN_MEM_SIZE=8589934592
++ cut -d . -f 9
++ ls /home/mcc/BenchKit/bin//..//itstools/plugins/fr.lip6.move.gal.application.pnmcc_1.0.0.202104292328.jar
+ VERSION=0
+ echo 'Running Version 0'
+ /home/mcc/BenchKit/bin//..//itstools/its-tools -data /home/mcc/execution/workspace -pnfolder /home/mcc/execution -examination ReachabilityCardinality -spotpath /home/mcc/BenchKit/bin//..//ltlfilt -z3path /home/mcc/BenchKit/bin//..//z3/bin/z3 -yices2path /home/mcc/BenchKit/bin//..//yices/bin/yices -its -ltsmin -greatspnpath /home/mcc/BenchKit/bin//..//greatspn/ -order META -manyOrder -smt -timeout 3600 -vmargs -Dosgi.locking=none -Declipse.stateSaveDelayInterval=-1 -Dosgi.configuration.area=/tmp/.eclipse -Xss128m -Xms40m -Xmx16000m

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="Diffusion2D-PT-D20N010"
export BK_EXAMINATION="ReachabilityCardinality"
export BK_TOOL="itstools"
export BK_RESULT_DIR="/tmp/BK_RESULTS/OUTPUTS"
export BK_TIME_CONFINEMENT="3600"
export BK_MEMORY_CONFINEMENT="16384"
export BK_BIN_PATH="/home/mcc/BenchKit/bin/"

# 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 Diffusion2D-PT-D20N010, examination is ReachabilityCardinality"
echo " Time confinement is $BK_TIME_CONFINEMENT seconds"
echo " Memory confinement is 16384 MBytes"
echo " Number of cores is 4"
echo " Run identifier is r083-tall-162048875000110"
echo "====================================================================="
echo
echo "--------------------"
echo "preparation of the directory to be used:"

tar xzf /home/mcc/BenchKit/INPUTS/Diffusion2D-PT-D20N010.tgz
mv Diffusion2D-PT-D20N010 execution
cd execution
if [ "ReachabilityCardinality" = "ReachabilityDeadlock" ] || [ "ReachabilityCardinality" = "UpperBounds" ] || [ "ReachabilityCardinality" = "QuasiLiveness" ] || [ "ReachabilityCardinality" = "StableMarking" ] || [ "ReachabilityCardinality" = "Liveness" ] || [ "ReachabilityCardinality" = "OneSafe" ] || [ "ReachabilityCardinality" = "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 [ "ReachabilityCardinality" = "UpperBounds" ] ; then
echo "The expected result is a vector of positive values"
echo NUM_VECTOR
elif [ "ReachabilityCardinality" != "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 "ReachabilityCardinality.txt" ] ; then
echo "here is the order used to build the result vector(from text file)"
for x in $(grep Property ReachabilityCardinality.txt | cut -d ' ' -f 2 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ -f "ReachabilityCardinality.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 '' ReachabilityCardinality.xml | cut -d '>' -f 2 | cut -d '<' -f 1 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ "ReachabilityCardinality" = "ReachabilityDeadlock" ] || [ "ReachabilityCardinality" = "QuasiLiveness" ] || [ "ReachabilityCardinality" = "StableMarking" ] || [ "ReachabilityCardinality" = "Liveness" ] || [ "ReachabilityCardinality" = "OneSafe" ] ; then
echo "FORMULA_NAME ReachabilityCardinality"
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 ;