Re: [mm/page_alloc] f26b3fa046: netperf.Throughput_Mbps -18.0% regression #forregzbot

[Thorsten Leemhuis <regressions@leemhuis.info>]

TWIMC: this mail is primarily send for documentation purposes and for
regzbot, my Linux kernel regression tracking bot. These mails usually
contain '#forregzbot' in the subject, to make them easy to spot and filter.

On 20.04.22 03:35, kernel test robot wrote:
> 
> (please be noted we reported
> "[mm/page_alloc]  39907a939a:  netperf.Throughput_Mbps -18.1% regression"
> on
> https://lore.kernel.org/all/20220228155733.GF1643@xsang-OptiPlex-9020/
> while the commit is on branch.
> now we still observe similar regression when it's on mainline, and we also
> observe a 13.2% improvement on another netperf subtest.
> so report again for information)
> 
> Greeting,
> 
> FYI, we noticed a -18.0% regression of netperf.Throughput_Mbps due to commit:
> 
> 
> commit: f26b3fa046116a7dedcaafe30083402113941451 ("mm/page_alloc: limit number of high-order pages on PCP during bulk free")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> 
> in testcase: netperf
> on test machine: 128 threads 2 sockets Intel(R) Xeon(R) Platinum 8358 CPU @ 2.60GHz with 128G memory
> with following parameters:
> 
> 	ip: ipv4
> 	runtime: 300s
> 	nr_threads: 1
> 	cluster: cs-localhost
> 	test: UDP_STREAM
> 	cpufreq_governor: performance
> 	ucode: 0xd000331
> 
> test-description: Netperf is a benchmark that can be use to measure various aspect of networking performance.
> test-url: http://www.netperf.org/netperf/
> [...]

This regression is discussed quite a bit currently, so let's better add
it to the tracking:

#regzbot ^introduced 39907a939a
#regzbot title mm: [mm/page_alloc]  f26b3fa046:  netperf.Throughput_Mbps
-18.0% regression
#regzbot ignore-activity

Ciao, Thorsten