mdbox + zlib performing less than just mdbox

Aki Tuomi aki.tuomi at open-xchange.com
Mon Jan 14 17:38:05 EET 2019


mdbox format is a cross between mbox and sdbox.

The idea is that it keeps up to mdbox_rotate_size sized mbox files which contain mails. Using zlib here will not help, because zlib is not applied to the full mdbox file, but individual mails within.

Also not sure why you think that adding compression would make things faster? =)

I am not fully sure how cephfs works but you might get better results with sdbox format.

Aki

> On 14 January 2019 at 17:30 Marc Roos <M.Roos at f1-outsourcing.eu> wrote:
> 
> 
> 
> I have test environment to determine what would be best settings. I have 
> been told that enabling zlib compression would be good to save iops on 
> storage. But doing the test now, I get worse results. 
> 
> [@test2 ~]# pr -m -t mail04-mdbox-vdb-append-64kb-6.log 
> mail04-mdbox-vdb-append-64kb-8.log |less
> Logi Sele Appe                      Logi Sele Appe
> 100% 100% 100%                      100% 100% 100%
>    1    1    6   1/  1                 1    1    6   1/  1
>    0    0    9   1/  1                 0    0    8   1/  1
>    0    0    7   1/  1                 0    0    8   1/  1
>    0    0   10   1/  1                 0    0    9   1/  1
>    0    0    7   1/  1                 0    0    6   1/  1
>    0    0    8   1/  1                 0    0    8   1/  1
>    0    0    9   1/  1                 0    0    8   1/  1
>    0    0   10   1/  1                 0    0    8   1/  1
>    0    0    9   1/  1                 0    0    7   1/  1
>    0    0   11   1/  1                 0    0    7   1/  1
>   29    3 1093 ms/cmd avg             43    2 1232 ms/cmd avg
> Logi Sele Appe                      Logi Sele Appe
> 100% 100% 100%                      100% 100% 100%
>    0    0   10   1/  1                 0    0    9   1/  1
>    0    0    9   1/  1                 0    0    7   1/  1
>    0    0   10   1/  1                 0    0    7   1/  1
>    0    0    9   1/  1                 0    0    6   1/  1
>    0    0   11   1/  1                 0    0    8   1/  1
>    0    0    9   1/  1                 0    0    7   1/  1
>    0    0    8   1/  1                 0    0    6   1/  1
>    0    0   11   1/  1                 0    0    7   1/  1
>    0    0    9   1/  1                 0    0    5   1/  1
>    0    0    9   1/  1                 0    0    9   1/  1
>    0    0 1063 ms/cmd avg              0    0 1413 ms/cmd avg
> Logi Sele Appe                      Logi Sele Appe
> 100% 100% 100%                      100% 100% 100%
>    0    0    8   1/  1                 0    0    8   1/  1
>    0    0   10   1/  1                 0    0    8   1/  1
>    0    0    7   1/  1                 0    0    8   1/  1
>    0    0   10   1/  1                 0    0    6   1/  1
>    0    0   10   1/  1                 0    0    7   1/  1
>    0    0   11   1/  1                 0    0    8   1/  1
>    0    0    7   1/  1                 0    0    8   1/  1
>    0    0   11   1/  1                 0    0    6   1/  1
>    0    0    8   1/  1                 0    0    7   1/  1
>    0    0   10   1/  1                 0    0    8   1/  1
>    0    0 1077 ms/cmd avg              0    0 1382 ms/cmd avg
> Logi Sele Appe                      Logi Sele Appe
> 100% 100% 100%                      100% 100% 100%
>    0    0    7   1/  1                 0    0    6   1/  1
>    0    0    9   1/  1                 0    0    4   1/  1
>    0    0    6   1/  1                 0    0    7   1/  1
>    0    0    9   1/  1                 0    0    7   1/  1
>    0    0    8   1/  1                 0    0    7   1/  1
>    0    0   10   1/  1                 0    0    5   1/  1
>    0    0    9   1/  1                 0    0    8   1/  1
>    0    0    7   1/  1                 0    0    6   1/  1
>    0    0    9   1/  1                 0    0    6   1/  1
>    0    0    7   1/  1                 0    0    8   1/  1
>    0    0 1246 ms/cmd avg              0    0 1524 ms/cmd avg
> ...
> ...
> ...
> Logi Sele Appe                      Logi Sele Appe
> 100% 100% 100%                      100% 100% 100%
>    0    0    8   1/  1                 0    0    5   1/  1
>    0    0    6   1/  1                 0    0    4   1/  1
>    0    0    6   1/  1                 0    0    4   1/  1
>    0    0    7   1/  1                 0    0    4   1/  1
>    0    0    5   1/  1                 0    0    5   1/  1
>    0    0    5   1/  1                 0    0    4   1/  1
>    0    0    6   1/  1                 0    0    4   1/  1
>    0    0    7   1/  1                 0    0    5   1/  1
>    0    0    6   1/  1                 0    0    4   1/  1
>    0    0    7   1/  1                 0    0    5   1/  1
>    0    0 1596 ms/cmd avg              0    0 2308 ms/cmd avg
> Logi Sele Appe                      Logi Sele Appe
> 100% 100% 100%                      100% 100% 100%
>    0    0    7   1/  1                 0    0    4   1/  1
>    0    0 1583 ms/cmd avg              0    0    4   1/  1
>                                        0    0 2331 ms/cmd avg
> Totals:
> Logi Sele Appe                      Totals:
> 100% 100% 100%                      Logi Sele Appe
>    1    1 1978                      100% 100% 100%
>                                        1    1 1145
> 
> 
> 
> 
> 
> 
>


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