Constructor for horizontally scalable storages.

Active "Work In Progress" - we already validated the concept and are working on a prototype. Goals:

• First OST prototype
• libRawStor extensive logic
• QEMU VM successful start and operation
• FIO backend implemented

• View our roadmap

(Some terms are borrowed from Lustre; an attentive reader may notice some similarities):

• **T (example - OST) - Target (shard)
• **S (example - OSS) - Server (node) with shards of this role

Components (roles):

• Object storage target (OST)
  • directly responsible for storing data (parts of objects)
  • per disk/partition
  • does not handle redundancy
• Metadata storage target (MDT)
  • stores mapping "part of object->OST"
  • in the case of block storage, it is largely static, used mainly for initial allocation
• Management server (MGS) (optional)
  • entry point with basic information about SDS (lists of MDS/OSS and so on)
• Client library
  • a library implementing a basic client for SDS
  • higher-level "facades" should be built on top of it, such as the QEMU driver, S3 gateway, and so on
  • what distinguishes rawstor from other solutions is that the responsibility for redundancy and data preparation lies expicitly on the client
  • if service operations in SDS (such as recovering redundancy when a server/disk fails) are needed, such logic should be based on the client library with one difference being that it can be run in another mode closer to the data

• first and initial example of OST server implementation

• first and initial example of client library implementation

• Principal architecture
• Protocol design

• see rawstor branch

• see rawstor branch