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Selection of Workstations

All workstations, that participate in remote memory paging are registered in a common file. These workstations are known as remote memory servers, while the workstations that run applications which use remote memory for swapping are called clients. Depending on its workload, a workstation may act as a server, or as a client, or as both, but only during a short transition interval. Along with the names, the load of the servers is also provided, so that prospective clients can locate the least loaded server.

All server workstations run a remote memory server that handles requests for page ins, page outs, as well as swap space allocation. When a client wants to swap out memory it picks the most promising server, asks for a number of page frames and starts sending requests to it. When a server runs out of memory, it denies further swap space allocation requests. When native memory-demanding processes start on a server workstation, the server's memory is swapped out to disk. Future requests will be serviced from the disk, and a note will be sent to the client, advising it to move its pages to another server, or its local disk.

Evangelos Markatos
Fri Mar 24 14:41:51 EET 1995