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Consider "updated" and "current" as two copies of routing table, where "current" table is the one used at the moment and "updated" is table of candidate routes to be published in the next publish event. This method prevents protocols to fill memory with buffered updates while "main" process is doing "publish", instead protocols sends the newest update directly to "main" process which then copies new update in "updated" table. A bit more complicated is OSPF, it does calculation in its own process and just sends the final result to the "main".
All currently used tasks and their allocated private/shared memory can be monitored using command:
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