Monthly Archives: June 2013

Ceph Placement Groups peering

The Peering state machine ( based on the Boost Statechart Library ) is in charge of making sure the OSDs supporting the placement groups are available, as described in the high level description of the peering process. It will then … Continue reading

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GLOCK is my favorite Cloud stack

GLOCK stands for GNU, Linux, OpenStack, Ceph and KVM. GNU is the free Operating System that guarantees my freedom and independance, Linux is versatile enough to accommodate for the heterogeneous hardware I’m using, OpenStack allows me to cooperatively run a … Continue reading

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Ceph disk requirements will be lower : a new backend is coming

When evaluating Ceph to run a new storage service, the replication factor only matters after the hardware provisionned from the start is almost full. It may happen months after the first user starts to store data. In the meantime a … Continue reading

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Merging Ceph placement group logs

Ceph stores objects in pools which are divided in placement groups. When an object is created, modified or deleted, the placement group logs the operation. If an OSD supporting the placement group is temporarily unavailable, the logs are used for … Continue reading

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Using the largest OpenStack tenant to define an architecture that scales out

The service offering of public cloud providers is designed to match many potential customers. It would be impossible to design the underlying architecture ( hardware and software ) to accommodate the casual individual as well as the need of the … Continue reading

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