Chapter 36. ISA erasure code plugin
The isa plugin is encapsulates the ISA library. It only runs on Intel processors.
To create a new jerasure erasure code profile:
ceph osd erasure-code-profile set <name> \
plugin=isa \
technique=<reed_sol_van|cauchy> \
[k=<data-chunks>] \
[m=<coding-chunks>] \
[ruleset-root=<root>] \
[ruleset-failure-domain=<bucket-type>] \
[directory=<directory>] \
[--force]Where:
k=<data chunks>
- Description
- Each object is split in data-chunks parts, each stored on a different OSD.
- Type
- Integer
- Required
- No.
- Default
- 7
m=<coding-chunks>
- Description
- Compute coding chunks for each object and store them on different OSDs. The number of coding chunks is also the number of OSDs that can be down without losing data.
- Type
- Integer
- Required
- No.
- Default
- 3
technique=<reed_sol_van or cauchy>
- Description
- The ISA plugin comes in two Reed Solomon forms. If reed_sol_van is set, it is Vandermonde, if cauchy is set, it is Cauchy.
- Type
- String
- Required
- No.
- Default
- reed_sol_van
ruleset-root=<root>
- Description
- The name of the crush bucket used for the first step of the ruleset. For intance step take default.
- Type
- String
- Required
- No.
- Default
- default
ruleset-failure-domain=<bucket-type>
- Description
- Ensure that no two chunks are in a bucket with the same failure domain. For instance, if the failure domain is host no two chunks will be stored on the same host. It is used to create a ruleset step such as step chooseleaf host.
- Type
- String
- Required
- No.
- Default
- host
directory=<directory>
- Description
- Set the directory name from which the erasure code plugin is loaded.
- Type
- String
- Required
- No.
- Default
- /usr/lib/ceph/erasure-code
--force
- Description
- Override an existing profile by the same name.
- Type
- String
- Required
- No.
