Re: [LKP] [btrfs] 302167c50b: fio.write_bw_MBps -12.4% regression

From: Huang\, Ying
Date: Fri May 24 2019 - 03:49:20 EST


"Huang, Ying" <ying.huang@xxxxxxxxx> writes:

> "Huang, Ying" <ying.huang@xxxxxxxxx> writes:
>
>> Hi, Josef,
>>
>> kernel test robot <rong.a.chen@xxxxxxxxx> writes:
>>
>>> Greeting,
>>>
>>> FYI, we noticed a -12.4% regression of fio.write_bw_MBps due to commit:
>>>
>>>
>>> commit: 302167c50b32e7fccc98994a91d40ddbbab04e52 ("btrfs: don't end
>>> the transaction for delayed refs in throttle")
>>> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git pending-fixes
>>>
>>> in testcase: fio-basic
>>> on test machine: 88 threads Intel(R) Xeon(R) CPU E5-2699 v4 @ 2.20GHz with 64G memory
>>> with following parameters:
>>>
>>> runtime: 300s
>>> nr_task: 8t
>>> disk: 1SSD
>>> fs: btrfs
>>> rw: randwrite
>>> bs: 4k
>>> ioengine: sync
>>> test_size: 400g
>>> cpufreq_governor: performance
>>> ucode: 0xb00002e
>>>
>>> test-description: Fio is a tool that will spawn a number of threads
>>> or processes doing a particular type of I/O action as specified by
>>> the user.
>>> test-url: https://github.com/axboe/fio
>>>
>>>
>>
>> Do you have time to take a look at this regression?
>
> Ping

Ping again.

Best Regards,
Huang, Ying