Execution Chart

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

Trace from the execution

Formatting '/data/fkordon/mcc2024-input.r225-tall-171649613700268.qcow2', fmt=qcow2 size=4294967296 backing_file=/data/fkordon/mcc2024-input.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
Waiting for the VM to be ready (probing ssh)
...............
=====================================================================
Generated by BenchKit 2-5568
Executing tool lola
Input is LamportFastMutEx-PT-3, examination is LTLFireability
Time confinement is 3600 seconds
Memory confinement is 16384 MBytes
Number of cores is 4
Run identifier is r225-tall-171649613700268
=====================================================================

--------------------
preparation of the directory to be used:
/home/mcc/execution
total 864K
-rw-r--r-- 1 mcc users 14K Apr 13 07:43 CTLCardinality.txt
-rw-r--r-- 1 mcc users 100K Apr 13 07:43 CTLCardinality.xml
-rw-r--r-- 1 mcc users 12K Apr 13 07:40 CTLFireability.txt
-rw-r--r-- 1 mcc users 69K Apr 13 07:40 CTLFireability.xml
-rw-r--r-- 1 mcc users 4.2K May 18 16:42 GenericPropertiesDefinition.xml
-rw-r--r-- 1 mcc users 6.6K May 18 16:42 GenericPropertiesVerdict.xml
-rw-r--r-- 1 mcc users 6.2K Apr 22 14:51 LTLCardinality.txt
-rw-r--r-- 1 mcc users 33K Apr 22 14:51 LTLCardinality.xml
-rw-r--r-- 1 mcc users 5.7K Apr 22 14:51 LTLFireability.txt
-rw-r--r-- 1 mcc users 30K Apr 22 14:51 LTLFireability.xml
-rw-r--r-- 1 mcc users 20K Apr 13 07:49 ReachabilityCardinality.txt
-rw-r--r-- 1 mcc users 136K Apr 13 07:49 ReachabilityCardinality.xml
-rw-r--r-- 1 mcc users 42K Apr 13 07:47 ReachabilityFireability.txt
-rw-r--r-- 1 mcc users 257K Apr 13 07:47 ReachabilityFireability.xml
-rw-r--r-- 1 mcc users 2.2K Apr 22 14:51 UpperBounds.txt
-rw-r--r-- 1 mcc users 5.0K Apr 22 14:51 UpperBounds.xml
-rw-r--r-- 1 mcc users 5 May 18 16:42 equiv_col
-rw-r--r-- 1 mcc users 2 May 18 16:42 instance
-rw-r--r-- 1 mcc users 6 May 18 16:42 iscolored
-rw-r--r-- 1 mcc users 77K May 18 16:42 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 LamportFastMutEx-PT-3-LTLFireability-00
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-01
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-02
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-03
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-04
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-05
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-06
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-07
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-08
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-09
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-10
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-11
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-12
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-13
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-14
FORMULA_NAME LamportFastMutEx-PT-3-LTLFireability-15

=== Now, execution of the tool begins

BK_START 1717053745198

FORMULA LamportFastMutEx-PT-3-LTLFireability-12 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-09 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-03 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-14 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-10 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-06 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-15 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-11 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-02 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-05 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-04 TRUE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-13 TRUE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-01 TRUE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-08 TRUE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-07 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
FORMULA LamportFastMutEx-PT-3-LTLFireability-00 FALSE TECHNIQUES COLLATERAL_PROCESSING EXPLICIT TOPOLOGICAL STATE_COMPRESSION STUBBORN_SETS USE_NUPN UNFOLDING_TO_PT
[lola] FINAL RESULTS
[lola]  FINISHED FORMULA: CATEGORY VALUE PRODUCED BY
[lola] LamportFastMutEx-PT-3-LTLFireability-00: LTL false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-01: F true state space / EG
[lola] LamportFastMutEx-PT-3-LTLFireability-02: CONJ false findpath
[lola] LamportFastMutEx-PT-3-LTLFireability-03: LTL false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-04: LTL true LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-05: CONJ false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-06: CONJ false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-07: LTL false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-08: LTL true LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-09: LTL false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-10: LTL false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-11: LTL false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-12: LTL false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-13: F true state space / EG
[lola] LamportFastMutEx-PT-3-LTLFireability-14: LTL false LTL model checker
[lola] LamportFastMutEx-PT-3-LTLFireability-15: LTL false LTL model checker
[lola]
[lola] Time elapsed: 0 secs. Pages in use: 1

BK_STOP 1717053745568

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

[lola][I] LoLA will run for 3600 seconds at most (--timelimit)
[lola][W] unknown unit in memory specification: using default
[lola][I] MEM LIMIT 5
[lola][I] NET
[lola][I] reading net from model.pnml
[lola][I] input: PNML file (--pnmlnet)
[lola][I] reading pnml
[lola][I] PNML file contains place/transition net
[lola][I] closed net file model.pnml
[lola][I] finished parsing
[lola][I] Reading formula.
[lola][I] Using XML format (--xmlformula)
[lola][I] reading XML formula
[lola][I] reading formula from LTLFireability.xml
[lola][I] Rule S: 42 transitions removed,29 places removed
[lola][I] LAUNCH task # 53 (type EXCL) for 52 LamportFastMutEx-PT-3-LTLFireability-12
[lola][I] time limit : 124 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 53 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-12
[lola][I] result : false
[lola][I] markings : 22
[lola][I] fired transitions : 22
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 44 (type EXCL) for 43 LamportFastMutEx-PT-3-LTLFireability-09
[lola][I] time limit : 144 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 44 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-09
[lola][I] result : false
[lola][I] markings : 85
[lola][I] fired transitions : 98
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 9 (type CNST) for 6 LamportFastMutEx-PT-3-LTLFireability-02
[lola][I] time limit : 0 sec
[lola][I] memory limit: 0 pages
[lola][I] FINISHED task # 9 (type CNST) for LamportFastMutEx-PT-3-LTLFireability-02
[lola][I] result : true
[lola][I] LAUNCH task # 18 (type EXCL) for 17 LamportFastMutEx-PT-3-LTLFireability-03
[lola][I] time limit : 200 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 18 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-03
[lola][I] result : false
[lola][I] markings : 61
[lola][I] fired transitions : 66
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 59 (type EXCL) for 58 LamportFastMutEx-PT-3-LTLFireability-14
[lola][I] time limit : 211 sec
[lola][I] memory limit: 2000 pages
[lola][I] LAUNCH task # 76 (type EQUN) for 6 LamportFastMutEx-PT-3-LTLFireability-02
[lola][I] time limit : 32000000 sec
[lola][I] memory limit: 5 pages
[lola][I] LAUNCH task # 69 (type FNDP) for 6 LamportFastMutEx-PT-3-LTLFireability-02
[lola][I] time limit : 32000000 sec
[lola][I] memory limit: 5 pages
[lola][I] LAUNCH task # 70 (type EQUN) for 6 LamportFastMutEx-PT-3-LTLFireability-02
[lola][I] time limit : 32000000 sec
[lola][I] memory limit: 5 pages
[lola][I] FINISHED task # 59 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-14
[lola][I] result : false
[lola][I] markings : 22
[lola][I] fired transitions : 22
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 47 (type EXCL) for 46 LamportFastMutEx-PT-3-LTLFireability-10
[lola][I] time limit : 225 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 47 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-10
[lola][I] result : false
[lola][I] markings : 22
[lola][I] fired transitions : 22
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 35 (type EXCL) for 30 LamportFastMutEx-PT-3-LTLFireability-06
[lola][I] time limit : 240 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 35 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-06
[lola][I] result : false
[lola][I] markings : 22
[lola][I] fired transitions : 22
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 62 (type EXCL) for 61 LamportFastMutEx-PT-3-LTLFireability-15
[lola][I] time limit : 276 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 62 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-15
[lola][I] result : false
[lola][I] markings : 22
[lola][I] fired transitions : 22
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 50 (type EXCL) for 49 LamportFastMutEx-PT-3-LTLFireability-11
[lola][I] time limit : 327 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 50 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-11
[lola][I] result : false
[lola][I] markings : 22
[lola][I] fired transitions : 22
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 28 (type EXCL) for 23 LamportFastMutEx-PT-3-LTLFireability-05
[lola][I] time limit : 360 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 69 (type FNDP) for LamportFastMutEx-PT-3-LTLFireability-02
[lola][I] result : true
[lola][I] tried executions : 1
[lola][I] time used : 0
[lola][I] memory pages used : 0
[lola][W] CANCELED task # 70 (type EQUN) for LamportFastMutEx-PT-3-LTLFireability-02 (obsolete)
[lola][W] CANCELED task # 76 (type EQUN) for LamportFastMutEx-PT-3-LTLFireability-02 (obsolete)
[lola][I] LAUNCH task # 86 (type EQUN) for 3 LamportFastMutEx-PT-3-LTLFireability-01
[lola][I] time limit : 32000000 sec
[lola][I] memory limit: 5 pages
[lola][I] LAUNCH task # 81 (type EQUN) for 55 LamportFastMutEx-PT-3-LTLFireability-13
[lola][I] time limit : 32000000 sec
[lola][I] memory limit: 5 pages
[lola][I] FINISHED task # 28 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-05
[lola][I] result : false
[lola][I] markings : 22
[lola][I] fired transitions : 22
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 21 (type EXCL) for 20 LamportFastMutEx-PT-3-LTLFireability-04
[lola][I] time limit : 600 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 21 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-04
[lola][I] result : true
[lola][I] markings : 1
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 78 (type EXCL) for 55 LamportFastMutEx-PT-3-LTLFireability-13
[lola][I] time limit : 720 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 78 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-13
[lola][I] result : false
[lola][I] markings : 1
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][W] CANCELED task # 81 (type EQUN) for LamportFastMutEx-PT-3-LTLFireability-13 (obsolete)
[lola][I] LAUNCH task # 83 (type EXCL) for 3 LamportFastMutEx-PT-3-LTLFireability-01
[lola][I] time limit : 900 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 83 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-01
[lola][I] result : false
[lola][I] markings : 1
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][W] CANCELED task # 86 (type EQUN) for LamportFastMutEx-PT-3-LTLFireability-01 (obsolete)
[lola][I] LAUNCH task # 41 (type EXCL) for 40 LamportFastMutEx-PT-3-LTLFireability-08
[lola][I] time limit : 1200 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 81 (type EQUN) for LamportFastMutEx-PT-3-LTLFireability-13
[lola][I] result : unknown
[lola][I] FINISHED task # 76 (type EQUN) for LamportFastMutEx-PT-3-LTLFireability-02
[lola][I] result : true
[lola][I] FINISHED task # 86 (type EQUN) for LamportFastMutEx-PT-3-LTLFireability-01
[lola][I] result : true
[lola][I] FINISHED task # 70 (type EQUN) for LamportFastMutEx-PT-3-LTLFireability-02
[lola][I] result : unknown
[lola][I] FINISHED task # 41 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-08
[lola][I] result : true
[lola][I] markings : 14449
[lola][I] fired transitions : 34141
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 38 (type EXCL) for 37 LamportFastMutEx-PT-3-LTLFireability-07
[lola][I] time limit : 1800 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 38 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-07
[lola][I] result : false
[lola][I] markings : 23
[lola][I] fired transitions : 24
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] LAUNCH task # 1 (type EXCL) for 0 LamportFastMutEx-PT-3-LTLFireability-00
[lola][I] time limit : 3600 sec
[lola][I] memory limit: 2000 pages
[lola][I] FINISHED task # 1 (type EXCL) for LamportFastMutEx-PT-3-LTLFireability-00
[lola][I] result : false
[lola][I] markings : 10
[lola][I] fired transitions : 10
[lola][I] time used : 0
[lola][I] memory pages used : 1
[lola][I] Portfolio finished: no open formulas

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="LamportFastMutEx-PT-3"
export BK_EXAMINATION="LTLFireability"
export BK_TOOL="lola"
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 2-5568"
echo " Executing tool lola"
echo " Input is LamportFastMutEx-PT-3, examination is LTLFireability"
echo " Time confinement is $BK_TIME_CONFINEMENT seconds"
echo " Memory confinement is 16384 MBytes"
echo " Number of cores is 4"
echo " Run identifier is r225-tall-171649613700268"
echo "====================================================================="
echo
echo "--------------------"
echo "preparation of the directory to be used:"

tar xzf /home/mcc/BenchKit/INPUTS/LamportFastMutEx-PT-3.tgz
mv LamportFastMutEx-PT-3 execution
cd execution
if [ "LTLFireability" = "ReachabilityDeadlock" ] || [ "LTLFireability" = "UpperBounds" ] || [ "LTLFireability" = "QuasiLiveness" ] || [ "LTLFireability" = "StableMarking" ] || [ "LTLFireability" = "Liveness" ] || [ "LTLFireability" = "OneSafe" ] || [ "LTLFireability" = "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 [ "LTLFireability" = "UpperBounds" ] ; then
echo "The expected result is a vector of positive values"
echo NUM_VECTOR
elif [ "LTLFireability" != "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 "LTLFireability.txt" ] ; then
echo "here is the order used to build the result vector(from text file)"
for x in $(grep Property LTLFireability.txt | cut -d ' ' -f 2 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ -f "LTLFireability.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 '' LTLFireability.xml | cut -d '>' -f 2 | cut -d '<' -f 1 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ "LTLFireability" = "ReachabilityDeadlock" ] || [ "LTLFireability" = "QuasiLiveness" ] || [ "LTLFireability" = "StableMarking" ] || [ "LTLFireability" = "Liveness" ] || [ "LTLFireability" = "OneSafe" ] ; then
echo "FORMULA_NAME LTLFireability"
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 ;