performance degradation on BlueField-2 5.15.0-1044-bluefield
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux-bluefield (Ubuntu) |
New
|
Undecided
|
Unassigned |
Bug Description
* Explain the bug(s)
We run a simple CPU-only xor application.
test.c
------
int main(void) {
long i;
int count = 0;
for (i=0; i< 10000000000; i++) {
}
return 0;
}
tested on BlueField-2 and found consistent performance degradation.
* Performance
install from debian kernel packages:
/auto/sw/
$ gcc test.c; time ./a.out
kernel 5.15.0-
kernel 5.15.0-
kernel 5.15.0-
kernel 5.15.0-
* Performance-2
However, If we download the kernel source and compile, then we don't see the difference
/boot/vmlinuz-
/boot/vmlinuz-
also test other versions
bf-1024
bf-1030
bf-1044
bf-1049
1024, 1030, 1044, 1049 all shows the same performance, 49 sec
root@c- 237-155- 120-p88- 00-0-bf2: /boot# diff config- 5.15.0- 1043-bluefield config- 5.15.0- 1044-bluefield 1043-bluefield Kernel Configuration 1044-bluefield Kernel Configuration VERSION_ SIGNATURE= "Ubuntu 5.15.0- 1043.45- bluefield 5.15.149" VERSION_ SIGNATURE= "Ubuntu 5.15.0- 1044.46- bluefield 5.15.152" NET_SCH_ CBQ=m NET_SCH_ ATM=m NET_SCH_ DSMARK= m
3c3
< # Linux/arm64 5.15.0-
---
> # Linux/arm64 5.15.0-
37c37
< CONFIG_
---
> CONFIG_
1663d1662
< CONFIG_
1666d1664
< CONFIG_
1678d1675
< CONFIG_
2154a2152
> # CONFIG_PCI_EPF_VNTB is not set