#8 h_vmem enforcement misbehavior in single node smp

[Anonymous]

I set h_vmem limits for a simple smp single execution node configuration.
The queued script launches 4 indipendent processing each of which allocates 1MB/10ms until killed by sge_shepherd.

[Anonymous]

allocates memory at fixed rate, until killed

[Anonymous]

sorry for the incomplete submission..

Using GE 6.2u5, installed from debian squeeze packages following
http://helms-deep.cable.nu/~rwh/blog/?p=159

I set up a very simple single node configuration, with 1 queue and with h_vmem limit enforced.
The attached testmem.c is compiled with gcc and run with the script
===== runme.sh ====================================
#!/bin/sh
# nome in coda
#$ -N provamarc
#
# shell di esecuzione
#$ -S /bin/sh
#
# Make sure that the .e and .o file arrive in the
# working directory
#$ -cwd
#
#Merge the standard out and standard error to one file
#$ -j y

./a.out > ./out.0.txt &
./a.out > ./out.1.txt &
./a.out > ./out.2.txt &
./a.out > ./out.3.txt
===================================================

Hence we have 4 independent processes per submission run, and 4 output files to chech at which allocation level (roughly) the process is killed.

I submit (non concurrently) the following scripts with the commands
1) qsub -pe smp 4 -l h_vmem=3.9G ./runme.sh
2) qsub -pe smp 4 -l h_vmem=4G ./runme.sh
3) qsub -pe smp 2 -l h_vmem=7.8G ./runme.sh
4) qsub -pe smp 2 -l h_vmem=8G ./runme.sh

sge_shepherd is expected to kill the processes as the SUM of the virtual memory used by the processes reaches the [slots]*[h_vmem] limit.

Such behavior is respected in runs 1), 3), but not in 2), 4), where the processes are killed only when they TAKEN SINGULARLY reach the [slots]*[h_vmem] limit.

In cases 2) 4), at the time the 4 process are killed the machine has already allocated 4*16Gb of memory.

It seems such behavior is consistent below and above the (roughly) 4Gb per process limit.

Just check if the behavior can be reproduced.

[Anonymous]

script, non-inlined version

[Anonymous]

testmem.c has been compiled with gcc version 4.4.5, and the machine has a 64bit debian squeeze OS, and 96Gb (plenty) of ram, 12 slots (cores).