Ceph

at the moment the output of "ceph df" does not take the crush ruleset into account to calculate the usage in percent of a pool.

example:

ceph df

GLOBAL:
SIZE AVAIL RAW USED %RAW USED
178T 137T 41811G 22.88
POOLS:
NAME ID USED %USED MAX AVAIL OBJECTS
test1 2 12896M 0.01 302G 645177
test2 3 559G 0.92 469G 143632
test3 4 20116G 22.01 51009G 5189436
test4 5 12299k 0 11172G 30

we look at pool "test2":
[..]
pool 3 'test2' replicated size 3 min_size 1 crush_ruleset 0

crushmap:
[..]
rule replicated_ruleset {
ruleset 0
type replicated
min_size 1
max_size 10
step take data
step chooseleaf firstn 0 type host
step emit
}

tree:
[..]
-1 3.27594 root data
-2 0.54599 host storage1
0 0.27299 osd.0 up 1.00000 1.00000
1 0.27299 osd.1 up 1.00000 1.00000
-3 0.54599 host storage2
2 0.27299 osd.2 up 1.00000 1.00000
3 0.27299 osd.3 up 1.00000 1.00000
-4 0.54599 host storage3
4 0.27299 osd.4 up 1.00000 1.00000
5 0.27299 osd.5 up 1.00000 1.00000
-5 0.54599 host storage4
6 0.27299 osd.6 up 1.00000 1.00000
7 0.27299 osd.7 up 1.00000 1.00000
-6 0.54599 host storage5
8 0.27299 osd.8 up 1.00000 1.00000
9 0.27299 osd.9 up 1.00000 1.00000
-7 0.54599 host storage6
10 0.27299 osd.10 up 1.00000 1.00000
11 0.27299 osd.11 up 1.00000 1.00000

ceph osd df
[..]
0 0.27299 1.00000 279G 131G 148G 46.97 2.05 119
1 0.27299 1.00000 279G 161G 117G 57.98 2.53 149
2 0.27299 1.00000 279G 117G 161G 42.21 1.84 107
3 0.27299 1.00000 279G 138G 140G 49.73 2.17 127
4 0.27299 1.00000 279G 135G 143G 48.50 2.12 124
5 0.27299 1.00000 279G 119G 159G 42.87 1.87 109
6 0.27299 1.00000 279G 145G 134G 51.99 2.27 133
7 0.27299 1.00000 279G 138G 141G 49.43 2.16 126
8 0.27299 1.00000 279G 143G 135G 51.48 2.25 131
9 0.27299 1.00000 279G 142G 137G 50.87 2.22 130
10 0.27299 1.00000 279G 152G 126G 54.61 2.39 139
11 0.27299 1.00000 279G 154G 124G 55.30 2.42 142

the OSDs for the pool are filled up about 50%
the usage shown by ceph df for the pool is 0.92%