Abstract: A method, product and apparatus for distributing retained messages information in a clustered publish/subscribe system. The method comprising obtaining a set of Retained Message Filters (RMFs) comprising a RMF for each server in the cluster, wherein the RMF representing a set of topics for which retained messages are retained by the server, the RMF being configured to approximate whether the server retains a retained message that matches a subscription; responsive to receiving a subscription request from a client, applying the set of RMFs to the subscription to obtain an indication of a set of servers that potentially retain retained messages that match the subscription; triggering each server in the set of servers to perform retrieval of retained messages that match the subscription; and sending to the client the retained messages retrieved from the servers in the set of servers.

Abstract: A publish-subscribe data messaging system in which wildcard subscriptions are represented in an approximate membership set or filter, such as a Bloom filter, for distribution to brokers together with formatting rules associated with the wildcard subscriptions, where a broker receiving a publication topic of a data publication for distribution to other brokers uses the formatting rules provided by any given broker to create wildcard versions of the publication topic for matching with the wildcard subscriptions that are represented in the approximate membership sets or filters provided by the given brokers, where, if a match exists, the data publication is forwarded to the given broker.

Abstract: Enhancing performance in a multicasting system. Flow rates in a multicasting system are monitored as system characteristics change. The multicasting system is operated based on a first mapping between data flows and multicasting groups. Data is disseminated by way of the mapping to subscribers to one or more of the data flows. The flow rate thresholds of satisfied flows are decreased to minimize the difference between the flow rate thresholds and respective target transmission rates of the satisfied flows, as the system's feasible data transmission workload is maintained with respect to subscriber reception rate capacities. The flow rate thresholds of unsatisfied flows are increased to minimize the difference between the flow rate threshold and respective target transmission rates for the unsatisfied flows and to limit occurrences of data transmission delays or losses, as the system's feasible data transmission workload is maintained with respect to subscriber reception rate capacities.

Abstract: A computer-implemented method includes sending one or more network packets. Each of the one or more network packets includes a network packet header. The computer implemented method further includes receiving a negative acknowledgement list comprising the network packets not received. The computer-implemented method further includes, responsive to the receiving of a negative acknowledgment list: For each network packet of the negative acknowledgment list, transforming the network packet header into a modified packet header to yield a modified packet. The computer-implemented method further includes combining each modified packet into a modified packet list. The computer-implemented method further includes generating one or more repair packets. Each of the one or more repair packets further include a repair packet header and a portion of the modified packet list. The computer-implemented method further includes sending the one or more repair packets.

Abstract: A computer-implemented method includes sending one or more network packets. Each of the one or more network packets includes a network packet header. The computer implemented method further includes receiving a negative acknowledgement list comprising the network packets not received. The computer-implemented method further includes, responsive to the receiving of a negative acknowledgment list: For each network packet of the negative acknowledgment list, transforming the network packet header into a modified packet header to yield a modified packet. The computer-implemented method further includes combining each modified packet into a modified packet list. The computer-implemented method further includes generating one or more repair packets. Each of the one or more repair packets further include a repair packet header and a portion of the modified packet list. The computer-implemented method further includes sending the one or more repair packets.

Abstract: A method comprising obtaining a Bloom filter array, wherein a size of a first Bloom filter is smaller than a size of a second Bloom filter and modifying at least a portion of the plurality of Bloom filters to create a modified Bloom filter array comprising a modified plurality of Bloom filters each of which having a same size, wherein the same size is greater than the size of the first Bloom filter, wherein said modifying comprises: duplicating the first Bloom filter to create a modified first Bloom filter comprising two or more concatenated copies of the first Bloom filter. The method may also include performing lookup in the Bloom filter array by computing a hash value of a key and accessing a bit in the hash value location in each Bloom filter of the modified Bloom filter array to determine lookup outcome in each Bloom filter.

Abstract: Method, system and product for efficient size reduction of a Bloom filter. The method includes: creating an interleaved Bloom filter based on a Bloom filter, wherein the interleaved Bloom filter is defined so as to have non-sequential cells of the Bloom filter be positioned sequentially, wherein the interleaved Bloom filter interleaves segments of the Bloom filter, wherein a size of the segments is based on an interleaving factor. A reduced size Bloom filter having a number cells below the number of cells of the Bloom filter is computed. The computation includes computing a value of a cell in the reduced size Bloom filter based on two or more values of cells in the interleaved Bloom filter.

Abstract: A method, product and apparatus for distributing retained messages information in a clustered publish/subscribe system. The method comprising obtaining a set of Retained Message Filters (RMFs) comprising a RMF for each server in the cluster, wherein the RMF representing a set of topics for which retained messages are retained by the server, the RMF being configured to approximate whether the server retains a retained message that matches a subscription; responsive to receiving a subscription request from a client, applying the set of RMFs to the subscription to obtain an indication of a set of servers that potentially retain retained messages that match the subscription; triggering each server in the set of servers to perform retrieval of retained messages that match the subscription; and sending to the client the retained messages retrieved from the servers in the set of servers.

Abstract: A computer-implemented method includes sending one or more network packets. Each of the one or more network packets includes a network packet header. The computer implemented method further includes receiving a negative acknowledgement list comprising the network packets not received. The computer-implemented method further includes, responsive to the receiving of a negative acknowledgment list: For each network packet of the negative acknowledgment list, transforming the network packet header into a modified packet header to yield a modified packet. The computer-implemented method further includes combining each modified packet into a modified packet list. The computer-implemented method further includes generating one or more repair packets. Each of the one or more repair packets further include a repair packet header and a portion of the modified packet list. The computer-implemented method further includes sending the one or more repair packets.

Abstract: A publish-subscribe data messaging system in which wildcard subscriptions are represented in an approximate membership set or filter, such as a Bloom filter, for distribution to brokers together with formatting rules associated with the wildcard subscriptions, where a broker receiving a publication topic of a data publication for distribution to other brokers uses the formatting rules provided by any given broker to create wildcard versions of the publication topic for matching with the wildcard subscriptions that are represented in the approximate membership sets or filters provided by the given brokers, where, if a match exists, the data publication is forwarded to the given broker.

Abstract: A process, a computer program product, and a computer system for redelivering a subset of messages in a packet to a receiver application are provided. The present invention enables the partially received packet to be delivered to the application layer (LLM) and allow LLM to decide whether it has to request for full packet retransmission or partial retransmission of the packet. The present invention allows the LLM of the receiver to generate a PNACK (partial negative-acknowledgement) based on the subset of the messages consumed from within the partial packet. The present invention allows the LLM of the transmitter to process the PNACK, to regenerate a new packet from the original packet to contain only a subset of the messages, and to send this new packet to the receiver who has generated the PNACK.

Abstract: A process, a computer program product, and a computer system for redelivering a subset of messages in a packet to a receiver application are provided. The present invention enables the partially received packet to be delivered to the application layer (LLM) and allow LLM to decide whether it has to request for full packet retransmission or partial retransmission of the packet. The present invention allows the LLM of the receiver to generate a PNACK (partial negative-acknowledgement) based on the subset of the messages consumed from within the partial packet. The present invention allows the LLM of the transmitter to process the PNACK, to regenerate a new packet from the original packet to contain only a subset of the messages, and to send this new packet to the receiver who has generated the PNACK.

Abstract: A process, a computer program product, and a computer system for redelivering a subset of messages in a packet to a receiver application are provided. The present invention enables the partially received packet to be delivered to the application layer (LLM) and allow LLM to decide whether it has to request for full packet retransmission or partial retransmission of the packet. The present invention allows the LLM of the receiver to generate a PNACK (partial negative-acknowledgement) based on the subset of the messages consumed from within the partial packet. The present invention allows the LLM of the transmitter to process the PNACK, to regenerate a new packet from the original packet to contain only a subset of the messages, and to send this new packet to the receiver who has generated the PNACK.

Abstract: A process, a computer program product, and a computer system for redelivering a subset of messages in a packet to a receiver application are provided. The present invention enables the partially received packet to be delivered to the application layer (LLM) and allow LLM to decide whether it has to request for full packet retransmission or partial retransmission of the packet. The present invention allows the LLM of the receiver to generate a PNACK (partial negative-acknowledgement) based on the subset of the messages consumed from within the partial packet. The present invention allows the LLM of the transmitter to process the PNACK, to regenerate a new packet from the original packet to contain only a subset of the messages, and to send this new packet to the receiver who has generated the PNACK.

Abstract: A method comprising using at least one hardware processor for managing persistent messaging data in a volatile memory, writing the persistent messaging data to a first section of a Fast Persistent Memory (FPM), responsive to the first section of the FPM approaching a full state, offloading the persistent messaging data from the first section of the FPM to a hard disk device (HDD), and erasing the persistent messaging data from the first section of the FPM, recording, in a second section of the FPM, an identifier of said offloading, responsive to receiving a request to erase or modify at least some of the persistent messaging data in the HDD, updating the identifier of the offloading in the second section of the FPM while leaving the persistent messaging data in the HDD intact, and responsive to a server failure, selectively reading at least some of the persistent messaging data from the HDD to the volatile memory, wherein the selective reading is based on the identifier of the offloading in the second section

Abstract: A method comprising managing persistent messaging data in a volatile memory of a primary instance of a multi-node server, wherein the persistent messaging data is stored in a Hard Disk Device (HDD) and a Fast Persistent Memory (FPM) of the primary instance, repeatedly replicating the persistent messaging data to a corresponding HDD and a corresponding FPM of at least one standby instance of the multi-node server, repeatedly copying the persistent messaging data stored in the FPM or the HDD of the at least one standby instance to a Recovery Memory Region (RMR) in a volatile memory of the at least one standby instance, and responsive to a failure of the primary instance, initiating a failover procedure by the standby instance, wherein the failover procedure comprises reading at least some of the persistent messaging data from the RMR in lieu of the HDD of the at least one standby instance.

Abstract: Enhancing performance in a multicasting system. Flow rates in a multicasting system are monitored as system characteristics change. The multicasting system is operated based on a first mapping between data flows and multicasting groups. Data is disseminated by way of the mapping to subscribers to one or more of the data flows. The flow rate thresholds of satisfied flows are decreased to minimize the difference between the flow rate thresholds and respective target transmission rates of the satisfied flows, as the system's feasible data transmission workload is maintained with respect to subscriber reception rate capacities. The flow rate thresholds of unsatisfied flows are increased to minimize the difference between the flow rate threshold and respective target transmission rates for the unsatisfied flows and to limit occurrences of data transmission delays or losses, as the system's feasible data transmission workload is maintained with respect to subscriber reception rate capacities.

Abstract: A method comprising managing persistent messaging data in a volatile memory of a primary instance of a multi-node server, wherein the persistent messaging data is stored in a Hard Disk Device (HDD) and a Fast Persistent Memory (FPM) of the primary instance, repeatedly replicating the persistent messaging data to a corresponding HDD and a corresponding FPM of at least one standby instance of the multi-node server, repeatedly copying the persistent messaging data stored in the FPM or the HDD of the at least one standby instance to a Recovery Memory Region (RMR) in a volatile memory of the at least one standby instance, and responsive to a failure of the primary instance, initiating a failover procedure by the standby instance, wherein the failover procedure comprises reading at least some of the persistent messaging data from the RMR in lieu of the HDD of the at least one standby instance.

Abstract: A method comprising using at least one hardware processor for managing persistent messaging data in a volatile memory, writing the persistent messaging data to a first section of a Fast Persistent Memory (FPM), responsive to the first section of the FPM approaching a full state, offloading the persistent messaging data from the first section of the FPM to a hard disk device (HDD), and erasing the persistent messaging data from the first section of the FPM, recording, in a second section of the FPM, an identifier of said offloading, responsive to receiving a request to erase or modify at least some of the persistent messaging data in the HDD, updating the identifier of the offloading in the second section of the FPM while leaving the persistent messaging data in the HDD intact, and responsive to a server failure, selectively reading at least some of the persistent messaging data from the HDD to the volatile memory, wherein the selective reading is based on the identifier of the offloading in the second section

Abstract: Enhancing performance in a multicasting system comprising monitoring filtering costs in a multicasting system as system characteristics change over time, wherein the multicasting system is operating based on a first mapping, between a plurality of data flows and multicasting groups, to disseminate data to users that subscribe to one or more of the data flows; computing a second mapping in response to determining that overhead associated with filtering of unwanted flows at the user level has exceeded a threshold; and transitioning the multicasting system from using the first mapping to using the second mapping, in response to determining that the second mapping is feasible as applicable to one or more constraints associated with the multicasting system.