12–NVMe-oF Configuration with RDMA
Optimizing Performance
196
AH0054601-00 B
.IRQ Affinity (multi_rss-affin.sh)
The following script sets the IRQ affinity.
#!/bin/bash
#RSS affinity setup script
#input: the device name (ethX)
#OFFSET=0 0/1 0/1/2 0/1/2/3
#FACTOR=1 2 3 4
OFFSET=0
FACTOR=1
LASTCPU='cat /proc/cpuinfo | grep processor | tail -n1 | cut -d":" -f2'
MAXCPUID='echo 2 $LASTCPU ^ p | dc'
OFFSET='echo 2 $OFFSET ^ p | dc'
FACTOR='echo 2 $FACTOR ^ p | dc'
CPUID=1
for eth in $*; do
NUM='grep $eth /proc/interrupts | wc -l'
NUM_FP=$((${NUM}))
INT='grep -m 1 $eth /proc/interrupts | cut -d ":" -f 1'
echo "$eth: ${NUM} (${NUM_FP} fast path) starting irq ${INT}"
CPUID=$((CPUID*OFFSET))
for ((A=1; A<=${NUM_FP}; A=${A}+1)) ; do
INT='grep -m $A $eth /proc/interrupts | tail -1 | cut -d ":" -f 1'
SMP='echo $CPUID 16 o p | dc'
echo ${INT} smp affinity set to ${SMP}
echo $((${SMP})) > /proc/irq/$((${INT}))/smp_affinity
CPUID=$((CPUID*FACTOR))
if [ ${CPUID} -gt ${MAXCPUID} ]; then
CPUID=1
CPUID=$((CPUID*OFFSET))
fi
done
done
