Techniques for managing processor resource for a multi-processor server executing multiple operating systems
A multiprocessor server system executes a plurality of multiprocessor or single-processor operating systems each using a plurality of storage adapters and a plurality of network adapters. Each operating system maintains load information about all its processors and shares the information with other operating systems. Upon changes in the processor load of the operating systems, processors are dynamically reassigned among operating systems to improve performance if the maximum load of the storage adapters and network adapters of the reassignment target operating system is not already reached. Processor reassignment includes shutting down and restarting dynamically operating systems to allow the reassignment of the processors used by single-processor operating systems. Furthermore, the process scheduler of multi-processor operating systems keeps some processors idle under light processor load conditions in order to allow the immediate reassignment of processors to heavily loaded operating systems.
1. A multiprocessor computer system, comprising:
a plurality of processors;
a plurality of storage system adapters coupled to a storage system;
a plurality of network adapters coupled to a network; and
a memory storing a plurality of operating systems each of which is executed using a subset of the plurality of processors, and wherein
each of the plurality of processors, storage system adapters and network adapters are assigned to one of the plurality of operating systems,
the operating systems specify at least one of the plurality of processors assigned to the operating systems that are in a low load condition and maintain the specified processors idle,
the plurality of operating systems share information indicating a current load of each of the plurality of processors, the plurality of storage system adapters, and the plurality of the network adapters,
each operating system to which at least one idle processor is assigned activates one of its idle processors when the average load of its active processors increases and activates one of its idle processors when the load of its storage adapters and the load of its network adapters do not exceed their maximum, and
one of the plurality of the operating systems reassigns to itself one of the plurality of processors that is idle and assigned to another operating system when the load of the processors assigned to the one operating system increases.
2. The multiprocessor computer system according to claim 1 , wherein the operating system executes processor reassignment when the load of its storage adapters and the load of its network adapters do not exceed their maximum.
3. A multiprocessor computer system, comprising:
a plurality of processors;
a plurality of storage system adapters coupled to a storage system;
a plurality of network adapters coupled to a network; and
a memory storing at least one multiprocessor operating system executed using a subset of the plurality of processors and at least one single-processor operating system executed using ode of the plurality of processors, and wherein
each of the plurality of processors, storage system adapters and network adapters are assigned to one of the at least one multiprocessor operating system or the at least one single-processor operating system,
the at least one multiprocessor operating system specifies at least one of the plurality of processors assigned to the multiprocessor operating system that is in a low load condition and maintains the specified processor idle,
the at least one multiprocessor operating system and the at least one single-processor operating system share information of a current load of each of the plurality of processors, the plurality of storage system adapters, and the plurality of the network adapters, and
the at least one multiprocessor operating system stops the execution of an idle single-processor operating system when its processor load increases above a threshold and reassigns to itself the processor, storage adapters, and network adapters assigned to the stopped single-processor operating system.
4. The multiprocessor computer system according to claim 3 ; wherein the multiprocessor operating system reassigns to itself the processor, storage adapters and network adapters of an idle single-processor operating system when the load of its storage adapters and network adapters do not exceed their maximum.
5. The multiprocessor computer system according to claim 3 ; wherein a multiprocessor operating system idles one of its processors if the load of its active processors decreases below a low threshold, and restarts a stopped single-processor operating system using the idled processor.