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@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