questions about erasure coded pool and rados

[yue longguang]

1. why erasure coded pool does not work with rbd?
2. i used rados command to put a file into erasue coded pool,then rm
it. why the file remains on osd's backend fs all the time?
3. what is the best use case with erasure coded pool?

4. command of 'rados ls' is to list objects, where are the object-name stored?
5.when a rbd file is put on erasure coded pool, where is the
infomation(rbd name) of the rbd stored?

thanks
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[Owen Synge]

An erasure encoded pool cannot be accessed directly using rbd. For this
reason we need a cache pool and an erasure pool. This not only allows
supporting rbd but increases performance.


http://karan-mj.blogspot.de/2014/04/erasure-coding-in-ceph.html
http://docs.ceph.com/docs/master/rados/operations/pools/
http://ceph.com/docs/master/rados/operations/cache-tiering/

Good luck

Owen

Post by yue longguang
1. why erasure coded pool does not work with rbd?
2. i used rados command to put a file into erasue coded pool,then rm
it. why the file remains on osd's backend fs all the time?
3. what is the best use case with erasure coded pool?
4. command of 'rados ls' is to list objects, where are the object-name stored?
5.when a rbd file is put on erasure coded pool, where is the
infomation(rbd name) of the rbd stored?
thanks
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More majordomo info at http://vger.kernel.org/majordomo-info.html

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[Loic Dachary]

Hi,

Post by yue longguang
1. why erasure coded pool does not work with rbd?
2. i used rados command to put a file into erasue coded pool,then rm
it. why the file remains on osd's backend fs all the time?

They will go away at some point but they are not removed from the file system immediately. There is however no risk that they re-appear in ceph ;-)

Cheers

Post by yue longguang
3. what is the best use case with erasure coded pool?
4. command of 'rados ls' is to list objects, where are the object-name stored?
5.when a rbd file is put on erasure coded pool, where is the
infomation(rbd name) of the rbd stored?
thanks
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To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
More majordomo info at http://vger.kernel.org/majordomo-info.html