Efficient flash memory-based object store

A method for durably storing data blocks maintained in a volatile cache on a solid state device, comprising:

• instantiating a plurality of threads that are each configured to perform work according to one of a plurality of stages,
• wherein the plurality of stages include:
• a first stage in which a thread identifies, in the volatile cache of a server that issues write requests to an object store maintained on one or more solid state devices, a first set of data blocks to write to a double-write buffer cache in non-volatile dynamic random access memory (DRAM),
• a second stage in which a thread writes a second set of data blocks from the volatile cache to the double-write buffer,
• a third stage in which a thread writes data from the double-write buffer to the one or more solid state devices, and
• wherein the plurality of threads include at least two threads that are both operating in different stages of the plurality of stages.

A distributed object store, comprising:

• one or more processors on one or more machines;
• and
• a machine readable medium storing one or more sequences of instructions, which when executed by the one or more processors, cause:
• maintaining the distributed object store on the plurality of solid state devices, wherein the distributed object store stores objects using a transaction model that ensures compliance with atomicity, concurrency, isolation, and durability (ACID) properties;
• the distributed object store providing parallel flushing in a write cache maintained on each of the plurality of solid state devices;
• and
• the distributed object store maintaining one or more double-write buffers, for the distributed object store, at a location other than the plurality of solid state devices.

A machine readable storage medium storing one or more sequences of instructions for durably storing data blocks maintained in a volatile cache on a solid state device, wherein execution of the one or more sequences of instruction cause:

• instantiating a plurality of threads that are each configured to perform work according to one of a plurality of stages,
• wherein the plurality of stages include:
• a first stage in which a thread identifies, in the volatile cache of a server that issues write requests to an object store maintained on one or more solid state devices, a first set of data blocks to write to a double-write buffer cache in non-volatile dynamic random access memory (DRAM),
• a second stage in which a thread writes a second set of data blocks from the volatile cache to the double-write buffer,
• a third stage in which a thread writes data from the double-write buffer to the one or more solid state devices, and
• wherein the plurality of threads include at least two threads that are both operating in different stages of the plurality of stages.