Re: refactoring basebackup.c

Hi,

I have repeated the experiment with 8K block size and found that the
results are not varying much after applying the patch.
Please find the details below.

*Backup type*: local backup using pg_basebackup
*Data size*: Around 200GB (200 tables - each table around 1.05 GB)
*TAR_SEND_SIZE value*: 8kb

*Server details:*
RAM: 500 GB CPU details: Architecture: x86_64 CPU op-mode(s): 32-bit,
64-bit Byte Order: Little Endian CPU(s): 128 Filesystem: ext4

*Results:*

Iteration WIthout refactor
patch WIth refactor
patch
1st run real 10m19.001s
user 1m37.895s
sys 8m33.008s real 9m45.291s
user 1m23.192s
sys 8m14.993s
2nd run real 9m33.970s
user 1m19.490s
sys 8m6.062s real 9m30.560s
user 1m22.124s
sys 8m0.979s
3rd run real 9m19.327s
user 1m21.772s
sys 7m50.613s real 8m59.241s
user 1m19.001s
sys 7m32.645s
4th run real 9m56.873s
user 1m22.370s
sys 8m27.054s real 9m52.290s
user 1m22.175s
sys 8m23.052s
5th run real 9m45.343s
user 1m23.113s
sys 8m15.418s real 9m49.633s
user 1m23.122s
sys 8m19.240s

Later I connected with Suraj to validate the experiment details and found
that the setup and steps followed are exactly the same in this
experiment when compared with the previous experiment.

Thanks,
Dipesh

On Thu, May 14, 2020 at 7:50 AM Suraj Kharage <
suraj(dot)kharage(at)enterprisedb(dot)com> wrote:

> Hi,
>
> On Wed, May 13, 2020 at 7:49 PM Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>
>>
>> So the patch came out slightly faster at 8kB and slightly slower in the
>> other tests. That's kinda strange. I wonder if it's just noise. How much do
>> the results vary run to run?
>>
> It is not varying much except for 8kB run. Please see below details for
> both runs of each scenario.
>
> 8kb 32kb (default value) 128kB 1024kB
> WIthout refactor
> patch 1st run real 10m50.924s
> user 1m29.774s
> sys 9m13.058s real 8m36.245s
> user 1m8.471s
> sys 7m21.520s real 7m8.690s
> user 0m54.840s
> sys 6m1.725s real 18m16.898s
> user 1m39.105s
> sys 9m42.803s
> 2nd run real 10m22.718s
> user 1m23.629s
> sys 8m51.410s real 8m44.455s
> user 1m7.896s
> sys 7m28.909s real 6m54.299s
> user 0m55.690s
> sys 5m46.502s real 18m3.511s
> user 1m38.197s
> sys 9m36.517s
> WIth refactor
> patch 1st run real 10m11.350s
> user 1m25.038s
> sys 8m39.226s real 8m56.226s
> user 1m9.774s
> sys 7m41.032s real 7m26.678s
> user 0m54.833s
> sys 6m20.057s real 19m5.218s
> user 1m44.122s
> sys 10m17.623s
> 2nd run real 11m30.500s
> user 1m45.221s
> sys 9m37.815s real 9m4.103s
> user 1m6.893s
> sys 7m49.393s real 7m26.713s
> user 0m54.868s
> sys 6m19.652s real 18m17.230s
> user 1m42.749s
> sys 9m53.704s
>
>
> --
> --
>
> Thanks & Regards,
> Suraj kharage,
> EnterpriseDB Corporation,
> The Postgres Database Company.
>