Abstract: The congestion notification system of some embodiments sends congestion notification messages from lower layer (e.g., closer to a network) components to higher layer (e.g., closer to a packet sender) components. When the higher layer components receive the congestion notification messages, the higher layer components reduce the sending rate of packets (in some cases the rate is reduced to zero) to allow the lower layer components to lower congestion (i.e., create more space in their queues by sending more data packets along the series of components). In some embodiments, the higher layer components resume full speed sending of packets after a threshold time elapses without further notification of congestion. In other embodiments, the higher layer components resume full speed sending of packets after receiving a message indicating reduced congestion in the lower layers.

Abstract: Some embodiments provide a method for reducing congestion in a network stack that includes a series of components that send data packets through the network stack to a network. At a first component of the network stack, the method receives a data packet from a second component of the network stack. The method identifies a usage indicator value for a flow to which the data packet belongs. The usage indicator value is based on a comparison of a size of the flow to a size of a queue for a third component of the network stack. The method determines whether to send the data packet based on a comparison of the usage indicator value to a threshold usage value. The method sends the data packet to a next component of the network stack only when the usage indicator value is less than the threshold usage value.

Abstract: The congestion notification system of some embodiments sends congestion notification messages from lower layer (e.g., closer to a network) components to higher layer (e.g., closer to a packet sender) components. When the higher layer components receive the congestion notification messages, the higher layer components reduce the sending rate of packets (in some cases the rate is reduced to zero) to allow the lower layer components to lower congestion (i.e., create more space in their queues by sending more data packets along the series of components). In some embodiments, the higher layer components resume full speed sending of packets after a threshold time elapses without further notification of congestion. In other embodiments, the higher layer components resume full speed sending of packets after receiving a message indicating reduced congestion in the lower layers.

Abstract: Some embodiments provide a method for reducing congestion in a network stack that includes a series of components that send data packets through the network stack to a network. At a first component of the network stack, the method receives a data packet from a second component of the network stack. The method identifies a usage indicator value for a flow to which the data packet belongs. The usage indicator value is based on a comparison of a size of the flow to a size of a queue for a third component of the network stack. The method determines whether to send the data packet based on a comparison of the usage indicator value to a threshold usage value. The method sends the data packet to a next component of the network stack only when the usage indicator value is less than the threshold usage value.

Abstract: The congestion notification system of some embodiments sends congestion notification messages from lower layer (e.g., closer to a network) components to higher layer (e.g., closer to a packet sender) components. When the higher layer components receive the congestion notification messages, the higher layer components reduce the sending rate of packets (in some cases the rate is reduced to zero) to allow the lower layer components to lower congestion (i.e., create more space in their queues by sending more data packets along the series of components). In some embodiments, the higher layer components resume full speed sending of packets after a threshold time elapses without further notification of congestion. In other embodiments, the higher layer components resume full speed sending of packets after receiving a message indicating reduced congestion in the lower layers.

Abstract: Some embodiments provide a method for reducing congestion in a network stack that includes a series of components that send data packets through the network stack to a network. At a first component of the network stack, the method receives a data packet from a second component of the network stack. The method identifies a usage indicator value for a flow to which the data packet belongs. The usage indicator value is based on a comparison of a size of the flow to a size of a queue for a third component of the network stack. The method determines whether to send the data packet based on a comparison of the usage indicator value to a threshold usage value. The method sends the data packet to a next component of the network stack only when the usage indicator value is less than the threshold usage value.

Abstract: Some embodiments provide a method for reducing congestion in a network stack that includes a series of components that send data packets through the network stack to a network. At a first component of the network stack, the method receives a data packet from a second component of the network stack. The method identifies a usage indicator value for a flow to which the data packet belongs. The usage indicator value is based on a comparison of a size of the flow to a size of a queue for a third component of the network stack. The method determines whether to send the data packet based on a comparison of the usage indicator value to a threshold usage value. The method sends the data packet to a next component of the network stack only when the usage indicator value is less than the threshold usage value.

Abstract: The congestion notification system of some embodiments sends congestion notification messages from lower layer (e.g., closer to a network) components to higher layer (e.g., closer to a packet sender) components. When the higher layer components receive the congestion notification messages, the higher layer components reduce the sending rate of packets (in some cases the rate is reduced to zero) to allow the lower layer components to lower congestion (i.e., create more space in their queues by sending more data packets along the series of components). In some embodiments, the higher layer components resume full speed sending of packets after a threshold time elapses without further notification of congestion. In other embodiments, the higher layer components resume full speed sending of packets after receiving a message indicating reduced congestion in the lower layers.