Maintaining a system state cache

摘要

Methods, apparatuses and computer software products implement embodiments of the present invention that include storing, to a module memory in each of a plurality of modules having multiple sub-modules, a record containing record entries corresponding respectively to the sub-modules. Upon detecting changes in respective states of the sub-modules of a given module, the corresponding record entries are set in response to the detected changes in the states of the sub-modules of the given module. A cache containing cache entries corresponding respectively to the sub-modules in the plurality of the modules is stored to a controller memory, and the record in each of the modules is polled. Upon detecting that a given record entry of the given module has been set, from the current state information with respect to the given sub-module is requested and received, and a corresponding cache entry is updated in the cache with the current state information.

主权项

1. A network switch, comprising:
a plurality of switching cores, each of the switching cores comprising:
multiple input/output ports for network communication;a switching-core memory configured to store a record containing multiple record entries corresponding respectively to the multiple ports; anda switching-core processor configured to:
(i) detect changes in respective states of the ports of the switching core, and, in response to the detected changes, set the corresponding record entries and transmit respective event reports indicating the changes, and(ii) receive a request for current state information with respect to one of the ports of the switching core, and, in response to the request, transmit the current state information; and a controller comprising:
a controller memory configured to store a cache containing cache entries corresponding respectively to the ports in the plurality of the switching cores; anda controller processor configured to:
(a) periodically poll the record in each of the switching cores, and upon detecting that a given record entry, corresponding to a given port of a given switching core, has been set, transmit the request for current state information with respect to the given port, receive the current state information from the switching-core processor of the given switching core, and update a corresponding cache entry in the cache with the current state information, and(b) receive the event reports indicating the changes in respective states of the ports, and, in response to the event reports, update the cache with respect to the changes.