D
–
Troubleshooting
Performance Issues
IB0054606-02 A
D-11
This method is not the first choice because, on some systems, there may be two
rows of
ib_qib
output, and you will not know which one of the two numbers to
choose. However, if you cannot find
$my_irq
listed under
/proc/irq
(Method 1), this type of system most likely has only one line for
ib_qib
listed in
/proc/interrupts
, so you can use Method 2.
Here is an example:
#
cat
/sys/class/infiniband/ipath*/device/
irq
98
#
ls /proc/irq
0 10
11 13 15 233
4 50 7 8 90
1 106
12 14 2 3
5 58 66 74 9
(Note that you cannot find 98.)
#
cat /proc/interrupts|grep ib_qib|awk \
’{print $1}’|sed -e ’s/://’
106
#
echo 01 > /proc/irq/106/smp_affinity
Using the
echo
command immediately changes the processor affinity of an IRQ.
You can look at the stats in
/proc/interrupts
while the adapter is active to
observe which CPU is fielding
ib_qib
interrupts.
Immediately change the processor affinity of an IRQ
To immediately change the processor affinity of an IRQ, execute a command
similar to the following, as a root user:
echo 01 > /proc/irq/$my_irq/smp_affinity
The contents of the
smp_affinity
file may not reflect the expected values, even
though the affinity change has taken place. If the driver is reloaded, the affinity
assignment will revert to the default, so you will need to reset it to the desired
value. Look at the stats in
/proc/interrupts
while the adapter is active to see
which CPU is fielding
ib_qib
interrupts.
NOTE
The contents of the
smp_affinity
file may not reflect the expected
values, even though the affinity change has taken place.
If the driver is reloaded, the affinity assignment will revert to the default,
so you will need to reset it to the desired value.
Summary of Contents for OFED+ Host
Page 1: ...IB0054606 02 A OFED Host Software Release 1 5 4 User Guide...
Page 14: ...xiv IB0054606 02 A OFED Host Software Release 1 5 4 User Guide...
Page 22: ...1 Introduction Interoperability 1 4 IB0054606 02 A...
Page 96: ...4 Running MPI on QLogic Adapters Debugging MPI Programs 4 24 IB0054606 02 A...
Page 140: ...6 SHMEM Description and Configuration SHMEM Benchmark Programs 6 32 IB0054606 02 A...
Page 148: ...8 Dispersive Routing 8 4 IB0054606 02 A...
Page 164: ...9 gPXE HTTP Boot Setup 9 16 IB0054606 02 A...
Page 176: ...A Benchmark Programs Benchmark 3 Messaging Rate Microbenchmarks A 12 IB0054606 02 A...
Page 202: ...B SRP Configuration OFED SRP Configuration B 26 IB0054606 02 A Notes...
Page 206: ...C Integration with a Batch Queuing System Clean up PSM Shared Memory Files C 4 IB0054606 02 A...
Page 238: ...E ULP Troubleshooting Troubleshooting SRP Issues E 20 IB0054606 02 A...
Page 242: ...F Write Combining Verify Write Combining is Working F 4 IB0054606 02 A Notes...
Page 280: ...G Commands and Files Summary of Configuration Files G 38 IB0054606 02 A...
Page 283: ......
