Oh, it's not working as intended though the ssd-primary rule is officially listed on ceph documentation. I should file a feature request or bugzilla for it?
Regards,
Horace Ng
Horace Ng
From: "Paul Emmerich" <paul.emmerich@xxxxxxxx>
To: "horace" <horace@xxxxxxxxx>
Cc: "ceph-users" <ceph-users@xxxxxxxxxxxxxx>
Sent: Wednesday, May 23, 2018 8:37:07 PM
Subject: Re: SSD-primary crush rule doesn't work as intended
To: "horace" <horace@xxxxxxxxx>
Cc: "ceph-users" <ceph-users@xxxxxxxxxxxxxx>
Sent: Wednesday, May 23, 2018 8:37:07 PM
Subject: Re: SSD-primary crush rule doesn't work as intended
You can't mix HDDs and SSDs in a server if you want to use such a rule.
The new selection step after "emit" can't know what server was selected previously.
Paul
2018-05-23 11:02 GMT+02:00 Horace <horace@xxxxxxxxx>:
Add to the info, I have a slightly modified rule to take advantage of the new storage class.
rule ssd-hybrid {
id 2
type replicated
min_size 1
max_size 10
step take default class ssd
step chooseleaf firstn 1 type host
step emit
step take default class hdd
step chooseleaf firstn -1 type host
step emit
}
Regards,
Horace Ng
----- Original Message -----
From: "horace" <horace@xxxxxxxxx>
To: "ceph-users" <ceph-users@xxxxxxxxxxxxxx>
Sent: Wednesday, May 23, 2018 3:56:20 PM
Subject: SSD-primary crush rule doesn't work as intended
I've set up the rule according to the doc, but some of the PGs are still being assigned to the same host.
http://docs.ceph.com/docs/master/rados/operations/crush-map-edits/
rule ssd-primary {
ruleset 5
type replicated
min_size 5
max_size 10
step take ssd
step chooseleaf firstn 1 type host
step emit
step take platter
step chooseleaf firstn -1 type host
step emit
}
Crush tree:
[root@ceph0 ~]# ceph osd crush tree
ID CLASS WEIGHT TYPE NAME
-1 58.63989 root default
-2 19.55095 host ceph0
0 hdd 2.73000 osd.0
1 hdd 2.73000 osd.1
2 hdd 2.73000 osd.2
3 hdd 2.73000 osd.3
12 hdd 4.54999 osd.12
15 hdd 3.71999 osd.15
18 ssd 0.20000 osd.18
19 ssd 0.16100 osd.19
-3 19.55095 host ceph1
4 hdd 2.73000 osd.4
5 hdd 2.73000 osd.5
6 hdd 2.73000 osd.6
7 hdd 2.73000 osd.7
13 hdd 4.54999 osd.13
16 hdd 3.71999 osd.16
20 ssd 0.16100 osd.20
21 ssd 0.20000 osd.21
-4 19.53799 host ceph2
8 hdd 2.73000 osd.8
9 hdd 2.73000 osd.9
10 hdd 2.73000 osd.10
11 hdd 2.73000 osd.11
14 hdd 3.71999 osd.14
17 hdd 4.54999 osd.17
22 ssd 0.18700 osd.22
23 ssd 0.16100 osd.23
#ceph pg ls-by-pool ssd-hybrid
27.8 1051 0 0 0 0 4399733760 1581 1581 active+clean 2018-05-23 06:20:56.088216 27957'185553 27959:368828 [23,1,11] 23 [23,1,11] 23 27953'182582 2018-05-23 06:20:56.088172 27843'162478 2018-05-20 18:28:20.118632
With osd.23 and osd.11 being assigned on the same host.
Regards,
Horace Ng
_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
--
--
Paul Emmerich
Looking for help with your Ceph cluster? Contact us at https://croit.io
croit GmbH
Freseniusstr. 31h
81247 München
www.croit.io
Tel: +49 89 1896585 90
Paul Emmerich
Looking for help with your Ceph cluster? Contact us at https://croit.io
croit GmbH
Freseniusstr. 31h
81247 München
www.croit.io
Tel: +49 89 1896585 90
_______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com