On Wed, Apr 12, 2017 at 09:33:28AM +0800, kernel test robot wrote:
>
> Greeting,
>
> FYI, we noticed a -4.3% regression of fsmark.files_per_sec due to commit:
>
>
> commit: 13c024422cbb6dcc513667be9a2613b0f0de781a ("irq/affinity: Assign all
> CPUs a vector")
> url:
> https://github.com/0day-ci/linux/commits/Keith-Busch/irq-affinity-Assign-all-CPUs-a-vector/20170401-035036
>
>
> in testcase: fsmark
> on test machine: 72 threads Intel(R) Xeon(R) CPU E5-2699 v3 @ 2.30GHz with
> 128G memory
> with following parameters:
>
> iterations: 8
> disk: 1SSD
> nr_threads: 4
> fs: btrfs
> filesize: 9B
> test_size: 16G
> sync_method: fsyncBeforeClose
> nr_directories: 16d
> nr_files_per_directory: 256fpd
> cpufreq_governor: performance
>
> test-description: The fsmark is a file system benchmark to test synchronous
> write workloads, for example, mail servers workload.
> test-url: https://sourceforge.net/projects/fsmark/
>
>
> Details are as below:
> -------------------------------------------------------------------------------------------------->
This wasn't supposed to change anything if all the nodes have the same
number of CPU's. I've reached out to the 0-day team to get a little more
information on the before/after smp affinity settings to see how this
algorithm messed up the spread on this system.
