Abstract: A computer-implemented method for preventing the occurrence of performance tickets in a computing system comprising a plurality of virtual machines hosted by a host computing system. The method comprising the steps of: monitoring a resource usage parameter associated with the workload of a virtual machine in order to obtain historic resource usage information; determining information regarding certain dependencies within the historic resource usage information; selecting partial information from the historic resource usage information based on said determined information regarding certain dependencies; estimating the future workload of the virtual machines based on said selected partial information; and resizing the computational resources of one or more virtual machines based on the estimated future workload such that a usage threshold of a computational resource is below a given threshold in order to avoid the generation of a performance ticket.

Abstract: A method for coordinating cache and memory reservation in a computerized system includes identifying at least one running application, recognizing the at least one application as a latency-critical application, monitoring information associated with a current cache access rate and a required memory bandwidth of the at least one application, allocating a cache partition, a size of the cache partition corresponds to the cache access rate and the required memory bandwidth of the at least one application, defining a threshold value including a number of cache misses per time unit, determining a reduction of cache misses per time unit, in response to the reduction of cache misses per time unit being above the threshold value, retaining the cache partition, assigning a priority of scheduling memory request including a medium priority level, and assigning a memory channel to the at least one application to avoid memory channel contention.

Abstract: A computing system comprises one or more multicore processor(s) comprising a set of multiple processing units each operable at a variable frequency, and a main memory operable at a variable frequency. A feedback controller is configured to control the frequency of each processing unit of the set and the frequency of the main memory dependent on a measure representative of a current performance of an application running on one or more of the multiple processing units of the set.

Abstract: The present invention is notably directed to systems and methods for detecting resource contention on a computerized system collocation of computer processes. Most basically, such methods comprise: monitoring data produced by each computer process of a set of computer processes co-located on the computerized system; detecting in the monitored data a change in a behavior of data produced by a given computer process of the set of computer processes; and throttling other computer processes of the set than said given computer process to detect potential resource contention at said given computer process. Such systems and methods advantageously apply to co-located virtual machines.

Abstract: A plurality of requests are received for computing processing. At least some of the plurality of requests are replicated. The requests are replicated based on a fractional replication factor. Each received request and each replicated request are transmitted to a computer resource for processing. At least some embodiments provide the capability for meeting tail latency targets with improved performance and reduced cost.

Abstract: A device is described. The device includes a daughterboard having a first distinct side and a second distinct side. A first connector on the first distinct side is attached to a first baseboard. A second connector on the second distinct side is attached to a second baseboard. A method for attaching a daughterboard to a second device is described. Connectors are included on opposing distinct sides of the daughterboard. The second device includes baseboards mechanically secured in parallel by lead screw actuators. As part of the method, the lead screw actuators are actuated so as to move the baseboards away from each other. A first connector is attached to one of the baseboards. The lead screw actuators are again actuated so as to move the baseboards toward each other until a second connector is brought into attachment with the other of the baseboards.

Abstract: A computer-implemented method for preventing the occurrence of performance tickets in a computing system comprising a plurality of virtual machines hosted by a host computing system. The method comprising the steps of: monitoring a resource usage parameter associated with the workload of a virtual machine in order to obtain historic resource usage information; determining information regarding certain dependencies within the historic resource usage information; selecting partial information from the historic resource usage information based on said determined information regarding certain dependencies; estimating the future workload of the virtual machines based on said selected partial information; and resizing the computational resources of one or more virtual machines based on the estimated future workload such that a usage threshold of a computational resource is below a given threshold in order to avoid the generation of a performance ticket.

Abstract: Congestion management for data traffic in a virtual domain identifies a congestion source and sends a message to the source to adjust data traffic rates. The source may be a virtual machine hosted by a physical server with one or more virtual servers incorporated. A congestion manager may identify the source and send the message to the source without affecting other data sources hosted by the physical server or the virtual servers. In some embodiments, information about the congestion source may be encapsulated in a packet payload readable only by the congestion source so only the congestion source receives the instruction to adjust the transmission rate.

Abstract: A virtual network is implemented on a physical network. A virtual network data packet is tunneled through the physical network via encapsulation within a physical network data packet and via transmission of the physical network data packet through the physical network. A network congestion notification capability of the virtual network is preserved and modified during transmission of virtual network data through the physical network and vice-versa. Congestion notification metadata can be copied from a header of a virtual network data packet to a header of a physical network data packet when the virtual network data packet is encapsulated into the physical network data packet. Congestion notification metadata can be copied from a header of a physical network data packet to a header of a virtual network data packet when the virtual network data packet is decapsulated from the physical network data packet.

Abstract: In one embodiment, a system includes a hardware processor and logic integrated with and/or executable by the processor, the logic being adapted to receive a traffic flow having a plurality of packets, classify the traffic flow into a traffic class based on a characteristic of the traffic flow, the traffic class being selected from a plurality of traffic classes, store an identifier of the selected traffic class to one or more of the packets, and transmit the traffic flow according to its destination based on a priority of its selected traffic class. In more embodiments, additional systems, methods, and computer program products for prioritizing traffic flow handling are described.

Abstract: Embodiments include pre-processing work items to be processed by computerized processing elements. Aspects include accessing a performance index, which relates to (dynamic) processing performances of work items as processed by the computerized processing elements. Aspects also include determining a time interval (during which the receiver may group queued work items into a block, according to the accessed performance index. Aspects further includes setting a timer to the determined time interval, to allow the receiver to group work items being queued until that time interval has elapsed, according to the timer set. As a result, a block of grouped work items will be obtained, which can then be passed to a scheduler for subsequent processing by computerized processing elements.

Abstract: Congestion management for data traffic in a virtual domain identifies a congestion source and sends a message to the source to adjust data traffic rates. The source may be a virtual machine hosted by a physical server with one or more virtual servers incorporated. A congestion manager may identify the source and send the message to the source without affecting other data sources hosted by the physical server or the virtual servers. In some embodiments, information about the congestion source may be encapsulated in a packet payload readable only by the congestion source so only the congestion source receives the instruction to adjust the transmission rate.

Abstract: The present invention is notably directed to systems and methods for detecting resource contention on a computerized system collocation of computer processes. Most basically, such methods comprise: monitoring data produced by each computer process of a set of computer processes co-located on the computerized system; detecting in the monitored data a change in a behavior of data produced by a given computer process of the set of computer processes; and throttling other computer processes of the set than said given computer process to detect potential resource contention at said given computer process. Such systems and methods advantageously apply to co-located virtual machines.

Abstract: The sizing of virtual machines is optimized based on projected performance metrics. All virtual machine configuration resources are normalized by a processing device. The normalized resources for the virtual machine configurations are then stored in a catalogue. An application is then profiled to obtain resource demand estimates for each virtual machine configuration and a base performance is calculated for the application. The base performance is used to predict performance estimates on all virtual machine configurations in the catalogue. Accordingly, a virtual machine configuration having a lowest response time is selected.

Abstract: A computing system comprises one or more multicore processor(s) comprising a set of multiple processing units each operable at a variable frequency, and a main memory operable at a variable frequency. A feedback controller is configured to control the frequency of each processing unit of the set and the frequency of the main memory dependent on a measure representative of a current performance of an application running on one or more of the multiple processing units of the set.

Abstract: A virtual network is implemented on a physical network. A virtual network data packet is tunneled through the physical network via encapsulation within a physical network data packet and via transmission of the physical network data packet through the physical network. A network congestion notification capability of the virtual network is preserved and modified during transmission of virtual network data through the physical network and vice-versa. Congestion notification metadata can be copied from a header of a virtual network data packet to a header of a physical network data packet when the virtual network data packet is encapsulated into the physical network data packet. Congestion notification metadata can be copied from a header of a physical network data packet to a header of a virtual network data packet when the virtual network data packet is decapsulated from the physical network data packet.

Abstract: A device is described. The device includes a daughterboard having a first distinct side and a second distinct side. A first connector on the first distinct side is attached to a first baseboard. A second connector on the second distinct side is attached to a second baseboard. A method for attaching a daughterboard to a second device is described. Connectors are included on opposing distinct sides of the daughterboard. The second device includes baseboards mechanically secured in parallel by lead screw actuators. As part of the method, the lead screw actuators are actuated so as to move the baseboards away from each other. A first connector is attached to one of the baseboards. The lead screw actuators are again actuated so as to move the baseboards toward each other until a second connector is brought into attachment with the other of the baseboards.

Abstract: Flow control of data packets in a network may be enabled to at least one side of a virtual switching interface to provide a lossless environment. In some embodiments, wherever two buffer queues are in communication with at least one buffer queue being connected to a virtual switching interface, flow control may be used to determine if a threshold has been exceeded in one of the buffer queues. When exceeded, the transmission of data packets may cease to one of the buffer queues to prevent packet dropping and loss of data.

Abstract: The sizing of virtual machines is optimized based on projected performance metrics. All virtual machine configuration resources are normalized by a processing device. The normalized resources for the virtual machine configurations are then stored in a catalog. An application is then profiled to obtain resource demand estimates for each virtual machine configuration and a base performance is calculated for the application. The base performance is used to predict performance estimates on all virtual machine configurations in the catalog. Accordingly, a virtual machine configuration having a lowest response time is selected.

Abstract: According to one embodiment, a method for handling congestion in a network includes determining that there is congestion on a first device in a network, setting a congestion indicator in a header of a packet to indicate an amount of congestion at the first device, sending the packet to all devices that send traffic to the first device, receiving the packet having the multi-bit indicator in a header thereof at a device that sends traffic to the first device, and reducing a congestion window by a factor of between about 5% and about 50% based on a severity of the congestion indicated by the multi-bit indicator, wherein the congestion window is reduced by a greater factor when the congestion is indicated as being more severe. Other systems and methods for handling congestion in a network are described according to more embodiments.