Adaptive power conservation in storage clusters

摘要

Each node and volume in a storage cluster makes a decision whether to reduce power consumption based on lack of requests from client applications and nodes over a time period. Node configuration parameters determine how long to wait until idling a node or volume, and how long to wait while idle before performing integrity checks. A bid value is calculated by each node and reflects how much it will cost for that node to write a file, read a file, or keep a copy. A node with the lowest bid wins, and nodes that are idle have a premium added to each bid to ensure that idle nodes are kept idle. In an archive mode, writes bids are reversed, nodes with less capacity submit lower bids, fuller nodes fill up faster and are then idled, while empty or near empty nodes may remain idle before winning a write bid.

主权项

1. A method of reading a computer file from a storage cluster having a plurality of computer nodes, said method comprising:
receiving at a first computer node of said storage cluster, a request from an external client application to retrieve said computer file from said storage cluster, each of said computer nodes of said storage cluster being in an idle state; sending a multicast message from said first computer node to said computer nodes in said storage cluster requesting a bid for reading said computer file; choosing one of said plurality of computer nodes based upon responses to said multicast message from said computer nodes, said computer file residing on said chosen computer node while said chosen computer node is in an idle state, said responses not requiring a disk access of said computer nodes; transitioning said chosen computer node and a disk volume of said chosen computer node that includes said computer file to an active state; maintaining computer nodes of said storage cluster that are not chosen in said idle state; and returning said computer file from said disk volume of said chosen computer node to said external client application.