메뉴 닫기

ceph pg 값 산출 계산(ceph 문서)

pg값을 막연하게 하나하나 주먹구구식으로 설정값을 찾다가 어떤 특정 패턴을 찾아 계산을 하면서 테스트를 진행해왔다.
그러던 중 계산기를 ceph 공개문서에서 찾았을때… 약간의 허무함?
아래의 내용은 ceph 공개문서에서 발췌한 내용으로 공개된 참고사항임을 먼저 말한다.
주의
다음의 내용을 바탕으로 값을 산출한다 하여도 절대값이 될 수 없음을 알고 있어야 한다.
시스템의 구성은 설계자 마다 다른 이유도 있으며, 그에 따라 값은 사용자에 맞게 변경해주어야 한다.
아래의 내용들은 평균적으로 산출되는 값이기 때문이다.
하지만 실제 사용하는 값들과 동떨어지지는 않으니 참고할 만한 공개 문서이다.

CEPH PGS PER POOL CALCULATOR

Instructions
Confirm your understanding of the fields by reading through the Key below.
Select a “Ceph Use Case” from the drop down menu.
Adjust the values in the “Green” shaded fields below, or click the highlighted values in the “Key” section below.
Tip: Headers can be clicked to change the value throughout the table.
You will see the Suggested PG Count update based on your inputs.
Click the “Add Pool” button to create a new line for a new pool.
Click the icon to delete the specific Pool.
For more details on the logic used and some important details, see the area below the table.
Once all values have been adjusted, click the “Generate Commands” button to get the pool creation commands.

Key

Pool Name Name of the pool in question. Typical pool names are included below.
Size Number of replicas the pool will have. Default value of 3 is pre-filled.
NOTE:For Erasure Coded Pools, select a ‘Size’ value equal to the sum of k + m.
The ‘Generate Commands’ button will not generate Erasure Coded pool commands,
so these will be up to you to create and configure properly.
OSD # Number of OSDs which this Pool will have PGs in. Typically, this is the entire Cluster OSD count, but could be less based on CRUSH rules.
(e.g. Separate SSD and SATA disk sets)
%Data This value represents the approximate percentage of data which will be contained in this pool for that specific OSD set.
Examples are pre-filled below for guidance.
Target PGs per OSD This value should be populated based on the following guidance:
100 If the cluster OSD count is not expected to increase in the foreseeable future.
200 If the cluster OSD count is expected to increase (up to double the size) in the foreseeable future.
300 If the cluster OSD count is expected to increase between 2x and 3x in the foreseeable future.

이상의 자동 계산기는 다음 링크를 참조 바란다.

http://ceph.com/pgcalc/

Subscribe
Notify of
guest
0 Comments
Inline Feedbacks
View all comments
0
Would love your thoughts, please comment.x
()
x