Patent ID: 8447894

Claim:
A server of an elastic computing cloud system which implements data storage based on storage services associated with block devices, comprising a block device driver apparatus and at least one block device service apparatus, wherein: the block device driver apparatus is configured to: place a received data write/read request in a waiting queue that is maintained in advance for a block device service apparatus in response to receiving the data write/read request corresponding to the block device service apparatus, fetch a data write/read request from the waiting queue and transfer the fetched request to a pending queue that is maintained in advance for the block device service apparatus, send a data write/read request in the pending queue to the block device service apparatus for processing, delete the sent data write/read request from the pending queue in response to receiving a processing result from the block device service apparatus for the data write/read request received, stop sending data write/read requests in the pending queue to the block device service apparatus for processing in response to determining that the block device service apparatus will perform a service upgrade, and transfer the data write/read requests in the pending queue back to the waiting queue in response to determining that a service upgrade will be performed or has been completed; and the block device service apparatus is configured to perform operations of reading and writing corresponding to requested data for a block device storage resource pool based on the data write/read request sent from the block device driver apparatus.