Remote or “cloud” computing typically utilizes a collection of remote servers in datacenters to provide computing, data storage, electronic communications, or other cloud services. The remote servers can be interconnected by computer networks to form one or more computing clusters. During operation, multiple remote servers or computing clusters can cooperate to provide a distributed computing environment that facilitates execution of user applications to provide cloud services.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
Servers in datacenters typically include a main processor with multiple “cores” that can operate independently, in parallel, or in other suitable manners to execute instructions. To facilitate communications with one another or with external devices, individual servers can also include a network interface controller (“NIC”) for interfacing with a computer network. A NIC typically includes hardware circuitry and/or firmware configured to enable communications between servers by transmitting/receiving data (e.g., as packets) via a network medium according to Ethernet, Fibre Channel, Wi-Fi, or other suitable physical and/or data link layer standards.
During operation, one or more cores of a processor in a server can cooperate with the NIC to facilitate communications to/from software components executing on the server. Example software components can include virtual machines, applications executing on the virtual machines, a hypervisor for hosting the virtual machines, or other suitable types of components. To facilitate communications to/from the software components, the one or more cores can execute suitable network processing operations to enforce communications security, perform network virtualization, translate network addresses, maintain a communication flow state, or perform other suitable functions.
One challenge for improving throughput to the software components on a server is to overcome limited processing capacities of the cores. During operation, executing network processing operations can overload the cores and thus render the cores as communications bottlenecks. A single core is typically used for executing network processing operations for a particular communication flow in order to maintain a proper communication flow state such as a proper sequence of transmitted packets. As available throughput of the NIC increases, a single core can become inadequate for executing network processing operations to accommodate operations of the NIC. As such, processing capabilities of the cores can limit transmission rates of data to/from software components on the server.
Embodiments of the disclosed technology can address certain aspects of the foregoing challenge by implementing hardware/software hybrid network processing load balancing in a server having a NIC operatively coupled to multiple cores. For example, the NIC can be configured to implement a hardware two-stage network processing load balancing by having electronic circuitry configured to provide (i) a first stage with a port selector configured to select a virtual port; and (ii) a serially coupled second stage with a receive side scaling (“RSS”) engine configured to further distribute network processing loads. Examples of such hardware electronic circuitry can include an application-specific integrated circuit (“ASIC”), a field programmable gate array (“FPGA”) with suitable firmware, or other suitable hardware components. A virtual port in a NIC is a virtual network interface corresponding to a hypervisor, a virtual machine, or other components hosted on a server. A virtual port can include one or more virtual channels (e.g., as queues) configured to receive and temporarily store packets associated with one or more communication flows (e.g., TCP/UDP flows). A communication flow can include an exchange of data (e.g., via a series of packets) during a communication session between two applications on servers.
At the first stage, the port selector can be configured to distribute incoming packets to a particular virtual port of the NIC based on a general destination of the incoming packets (e.g., a virtual machine). In one example, the port selector can be configured to filter the incoming packets based on a media access control address (“MAC” address) or a combination of a MAC address and a virtual network tag included in headers of the packets. The filtered packets associated with a particular MAC address are then assigned to a virtual port associated with a virtual machine on the server. In other implementations, the port selector can be configured to filter the incoming packets based on a virtual machine identifier, a virtual machine IP address, or other suitable identifiers.
At the second stage, the RSS engine can be configured to further distribute the incoming packets assigned to a virtual port to multiple queues in the virtual port based on a particular destination of the packets (e.g., one or more applications executing on the virtual machine). For example, in one implementation, the RSS engine can be configured to calculate a first hash value (e.g., 32 bits) based on a source IP address, a destination IP address, a source port, a destination port, and/or other suitable Transmission Control Protocol (“TCP”) parameters (referred to as “characteristic of communication”) of the packets. The RSS engine can then assign the packets to a queue in the virtual port based on one or more bits of the calculated first hash value by consulting a first indirection table associated with the virtual port. The first indirection table contains assignments of individual queues based on the one or more bits of the first hash value. The assigned queue can then receive and temporarily store the packets.
The server can also include a software implemented RSS switch operatively coupled to the hardware implemented RSS engine in the NIC. The software implemented RSS switch can be configured to further distribute processing loads of packets from a single queue of a virtual port in the NIC to multiple cores of the server. In certain embodiments, the RSS switch can be provided by executing suitable instructions with a single core of the server (e.g., the first core). In other embodiments, the RSS switch can be provided by executing suitable instructions in other suitable manners. In one implementation, the RSS switch can include a software implemented hash module configured to calculate a second hash value of the packets based on at least a part of the characteristic of communication of the packets. The RSS switch can also include an assignment module configured to assign network processing loads associated with the packets to a particular core in the server based on one or more bits of the calculated second hash value by consulting a second indirection table containing assignments of individual cores corresponding to one or more bits of the second hash value. With the identified core, the NIC can then cooperate with the identified core to forward the packets to the particular destination on the server.
Several embodiments of the disclosed technology can improve network data throughput to applications, virtual machines, or other software components on a server when compared to other communication techniques. In certain computing systems, RSS operations can be implemented as a software component, for example, a module of an operating system executed by a core on the server. However, using a generic main processor for performing RSS operations such as hash calculations can be highly inefficient. For instance, in one test, a server having software implemented RSS engine could only achieve about 26 Gbit/s of network data transmission when the NIC has a capacity of 40 Gbit/s. The software implemented RSS engine can also suffer from performance jitters or variances when the core experiences operational delays and other undesirable effects. By offloading execution of a portion of the RSS operations to the hardware implemented RSS engine in the NIC, data throughput in the server can be significantly improved. For instance, in another test, a server having a hardware implemented RSS engine achieved close to 40 Gbit/s of network data transmission when the NIC has a capacity of 40 Gbit/s.
Various embodiments of computing systems, devices, components, modules, routines, and processes related to hybrid network processing load balancing in computing devices and systems are described below. In the following description, example software codes, values, and other specific details are included to provide a thorough understanding of various embodiments of the present technology. A person skilled in the relevant art will also understand that the technology may have additional embodiments. The technology may also be practiced without several of the details of the embodiments described below with reference to
As used herein, the term a “computing system” generally refers to an interconnected computer network having a plurality of network devices that interconnect a plurality of servers or hosts to one another or to external networks (e.g., the Internet). The term “network device” generally refers to a physical network device, examples of which include routers, switches, hubs, bridges, load balancers, security gateways, or firewalls. A “host” generally refers to a computing device configured to implement, for instance, one or more virtual machines or other suitable virtualized components. For example, a host can include a server having a hypervisor configured to support one or more virtual machines or other suitable types of virtual components.
A computer network can be conceptually divided into an overlay network implemented over an underlay network. An “overlay network” generally refers to an abstracted network implemented over and operating on top of an underlay network. The underlay network can include multiple physical network devices interconnected with one another. An overlay network can include one or more virtual networks. A “virtual network” generally refers to an abstraction of a portion of the underlay network in the overlay network. A virtual network can include one or more virtual end points referred to as “tenant sites” individually used by a user or “tenant” to access the virtual network and associated computing, storage, or other suitable resources. A tenant site can have one or more tenant end points (“TEPs”), for example, virtual machines. The virtual networks can interconnect multiple TEPs on different hosts. Virtual network devices in the overlay network can be connected to one another by virtual links individually corresponding to one or more network routes along one or more physical network devices in the underlay network.
Also used herein, a “packet” generally refers to a formatted unit of data carried by a packet-switched or other suitable types of network. A packet typically include both control information and user data referred to as payload. Control information can provide data for transmitting or delivering a payload. For example, control information can include source and destination network addresses, error detection codes (e.g., CRC codes), sequencing information, and/or other suitable data. Typically, control information can be contained in packet headers that precede the payload and trailers that follow the payload. An example header is described below with reference to
A “virtual port” generally refers to a virtual network interface on a NIC that corresponds to a hypervisor, a virtual machine, or other components hosted on a computing device. A virtual port can include one or more virtual channels (e.g., as queues) that can be assigned to packets associated with a single communication flow. Each queue can be affinitized with a single core of a main processor in the server. The term “affinitize” generally refers to an assignment, designation, or association for establishing a relationship between a queue in a virtual port with a single core in the main processor in the server.
Servers in datacenters typically include a main processor with multiple cores to execute instructions independently, cooperatively, or in other suitable manners. The servers can also include a NIC for interfacing with a computer network. The NIC can facilitate, for example, transmission and reception of packets via a network medium according to Ethernet, Fibre Channel, Wi-Fi, or other suitable standards. During operation, one or more cores in a server can cooperate with the NIC to facilitate communications via the computer network. The core can execute instructions to enforce communications security, perform network virtualization, translate network addresses, maintaining a communication flow state, or perform other suitable functions.
One challenge for improving throughput to virtual machines or applications executing in the virtual machines on a server is that the cores can be overloaded with executing the network processing operations or loads and become communications bottlenecks. Typically, a single core is used for executing network processing loads for a communication flow to maintain a proper communication flow state, e.g., a proper sequence of transmitted packets. As available throughput of the NIC increases, a single core can have inadequate processing capability to execute the network processing loads to accommodate the throughput of the NIC. As such, processing capabilities of the cores can limit transmission rates of network data to/from applications, virtual machines, or other software components executing on the servers.
Several embodiments of the disclosed technology can address certain aspects of the foregoing challenge by implementing hardware/software hybrid network processing load balancing in a server having a NIC operatively coupled to multiple cores in a server. In certain embodiments, the NIC can be configured to implement two-stage hardware network processing load balancing by having (i) a first stage with a port selector and, in series with the first stage, (ii) a second stage with a receive side scaling (“RSS”) engine. At the first stage, the port selector can be configured to distribute incoming packets to a particular virtual port of the NIC based on MAC addresses of the incoming packets. At the second stage, the RSS engine can be configured to further distribute the incoming packets assigned to a virtual port to multiple queues in the virtual port based on characteristic of communication of the packets. The server can also include a software implemented RSS switch configured to further distribute network processing loads of packets in a single queue of a virtual port in the NIC to multiple cores in the server. The NIC can then cooperate with the identified core to forward the packets to suitable applications, virtual machines, or other software components on the server, as described in more detail below with reference to
As shown in
The hosts 106 can individually be configured to provide computing, storage, and/or other suitable cloud computing services to the individual tenants 101. For example, as described in more detail below with reference to
The client devices 102 can each include a computing device that facilitates corresponding users 101 to access cloud services provided by the hosts 106 via the underlay network 108. For example, in the illustrated embodiment, the client devices 102 individually include a desktop computer. In other embodiments, the client devices 102 can also include laptop computers, tablet computers, smartphones, or other suitable computing devices. Even though three users 101 are shown in
The first host 106a and the second host 106b can individually contain instructions in the memory 134 executable by the processors 132 to cause the individual processors 132 to provide a hypervisor 140 (identified individually as first and second hypervisors 140a and 140b). The hypervisors 140 can be individually configured to generate, monitor, terminate, and/or otherwise manage one or more virtual machines 144 organized into tenant sites 142. For example, as shown in
Also shown in
The virtual machines 144 on the virtual networks 146 can communicate with one another via the underlay network 108 (
In operation, the hosts 106 can facilitate communications among the virtual machines and/or applications executing in the virtual machines 144. For example, the processor 132 can execute suitable network communication operations to facilitate the first virtual machine 144′ to transmit packets to the second virtual machine 144″ via the virtual network 146a by traversing the network interface 136 on the first host 106a, the underlay network 108 (
In
Components within a system may take different forms within the system. As one example, a system comprising a first component, a second component, and a third component. The foregoing components can, without limitation, encompass a system that has the first component being a property in source code, the second component being a binary compiled library, and the third component being a thread created at runtime. The computer program, procedure, or process may be compiled into object, intermediate, or machine code and presented for execution by one or more processors of a personal computer, a tablet computer, a network server, a laptop computer, a smartphone, and/or other suitable computing devices.
Equally, components may include hardware circuitry. In certain examples, hardware may be considered fossilized software, and software may be considered liquefied hardware. As just one example, software instructions in a component may be burned to a Programmable Logic Array circuit, or may be designed as a hardware component with appropriate integrated circuits. Equally, hardware may be emulated by software. Various implementations of source, intermediate, and/or object code and associated data may be stored in a computer memory that includes read-only memory, random-access memory, magnetic disk storage media, optical storage media, flash memory devices, and/or other suitable computer readable storage media. As used herein, the term “computer readable storage media” excludes propagated signals.
As shown in
The processor 132 can be an electronic package containing various components configured to perform arithmetic, logical, control, and/or input/output operations. The processor 132 can be configured to execute instructions to provide suitable computing services, for example, in response to a user request received from the client device 102 (
The main memory 134 can include a digital storage circuit directly accessible by the processor 132 via, for example, a data bus 131. In one embodiment, the data bus 131 can include an inter-integrated circuit bus or I2C bus as detailed by NXP Semiconductors N.V. of Eindhoven, the Netherlands. In other embodiments, the data bus 131 can also include a PCIe bus, system management bus, RS-232, small computer system interface bus, or other suitable types of control and/or communications bus. In certain embodiments, the main memory 134 can include one or more DRAM modules. In other embodiments, the main memory 134 can also include magnetic core memory or other suitable types of memory.
As shown in
The individual virtual machines 144 can include a corresponding virtual interface 145 (identified as first virtual interface 145a and second virtual interface 145b) for receiving/transmitting data packets via the virtual network 108′. In certain embodiments, the virtual interfaces 145 can each be a virtualized representation of resources at the network interface 136 (or portions thereof). For example, the virtual interfaces 145 can each include a virtual Ethernet or other suitable types of interface that shares physical resources at the network interface 136. Even though only one virtual interface 145 is shown for each virtual machine 144, in further embodiments, a single virtual machine 144 can include multiple virtual interfaces 145 (not shown).
The network interface 136 can be configured to facilitate virtual machines 144 and/or applications 147 executing on the host 106 to communicate with other components (e.g., other virtual machines 144 on other hosts 106) on the virtual networks 146 (
As shown in
The virtual ports 139 can be configured to interface with one or more software components executing on the host 106. For example, as shown in
As shown in
As shown in
The packet handler 125 can be configured to facilitate operations related to receiving and transmission of packets 150. For example, in certain embodiments, the packet handler 125 can include a receive de-serializer, a CRC generator/checker, a transmit serializer, an address recognition module, a first-in-first-out control module, and a protocol control module. In other embodiments, the packet handler 125 can also include other suitable modules in addition to or in lieu of the foregoing modules. As described in more detail below, the packet handler 125 can also cooperate with the port selector 126 and the RSS engine 128 to process and forward packets 150 to the virtual machines 144 and/or the application 147.
In accordance with embodiments of the disclosed technology, the network interface 136 can be implemented with two-stage network processing load balance by utilizing the port selector 126 as a first stage and the RSS engine 128 as a second stage in the hardware electronic circuitry of the controller 122. In particular, The port selector 126 can be configured to distribute incoming packets 150 to a particular virtual port 138 of the network interface 136 by identifying a general destination of the incoming packets 150 (e.g., a virtual machine 144). For example, the port selector 126 can be configured to filter the incoming packets 150 based on a media access control address (“MAC” address) included in headers of the packets 150. The filtered packets 150 associated with a particular MAC address are then assigned to a virtual port 138 associated with a virtual machine 144 on the host 106. For instance, as shown in
As shown in
Upon identifying the particular destination, the RSS engine 128 can then assign the packets 150 and 150′ to a queue 139 in the virtual port 138 based on one or more bits of the calculated hash value by consulting an indirection table associated with the virtual port 138. The indirection table can be contained in the memory 124, a persistent storage (not shown), or in other suitable locations of the network interface 136. The indirection table can contain assignments or otherwise indicate the individual queues 139 corresponding to one or more bits of the calculated hash value. The following is an example indirection table for the illustrated example in
In the illustrated example, the RSS engine 128 selects the third queue 139c (shown in reverse contrast) for both the packets 150 and 150′ based on the characteristic of communication of the packets 150 and 150′. In certain embodiments, the packets 150 and 150′ can both be assigned to the third queue 139c due to a limited number of the queues 139 in the first virtual port 138a. Thus, the first and second queues 139a and 139b may both be used or otherwise unavailable. In other embodiments, the packets 150 and 150′ can both be assigned to the third queue 139c due to other suitable reasons. Example implementations of the RSS engine 128 are described below with reference to
With the identified queue 139, the packet handler 125 of the network interface 136 can then indicate to the processor 132 (or a software component executing thereon) that packets 150 and 150′ in the third queue 139c of the first virtual port 138a is ready for further processing. In certain implementations, the packet handler 125 can detect that a certain amount of data (e.g., a number of packets 150 and 150′) have been received in the third queue 139c. In response, the packet handler 125 can generate an interrupt to the processor 132 to schedule a remote procedure call on one of the cores 133 for processing the packets 150 and 150′. In response, the processor 132 can invoke the RSS switch 135 to further distribute network processing loads for processing the packets 150 and 150′.
As shown in
As illustrated in
Once the cores 133 are assigned for the packets 150 and 150′, the processor 132 can cause the assigned cores 133 (e.g., the third and fourth cores 133c and 133d) to initiate execution of the network processing operations. In certain embodiments, the processor 132 can schedule remote procedure calls at the third and fourth cores 133c and 133d. Once the remote procedure calls are executed, the third and fourth cores 133c and 133d (shown in reverse contrast) can inspect and retrieve the packets 150 and 150′ from the third queue 139c of the first virtual port 138a, perform suitable processing on the retrieved packets 150 and 150′, and forward the processed packet 150 and 150′ to the first virtual machine 144a, as shown in
In operation, the MAU 123 receives the packets 150 and 150′ via the underlay network 108 (
In response to receiving the indication from the network interface packet handler 125, the RSS switch 135 implemented as a software component executing on one of the cores 133 (e.g., the first core 133a in
Subsequently, the RSS engine 128 can further distribute the packets 150 and 150′ to individual queues 139 in the first and second virtual ports 138a and 138b based on a characteristic of communication of the packets 150 and 150′, respectively. For example, as shown in
In response, the RSS switch 135 can assign corresponding cores 133 to execute network processing operations for the packets 150 and 150′, respectively. For example, as shown in
Several embodiments of the disclosed technology can improve network data throughput to applications 147, virtual machines 144, or other software components on a host 106 when compared to other communication techniques. In certain computing systems, RSS operations are only implemented as a software component, for example, a module of an operating system executed by a core on the server. However, using a generic main processor for performing RSS operations such as hash calculations can be highly inefficient. For instance, in one test, a server having software implemented RSS engine could only achieve about 26 Gbit/s of network data transmission when the NIC has a capacity of 40 Gbit/s. The software implemented RSS engine can also suffer from performance jitters or variances when the core experiences operational delays and other undesirable effects. By offloading at least a portion of executing RSS operations to the hardware implemented RSS engine 128 in the network interface 136, data throughput in the host 106 can be significantly improved. For instance, in another test, a server having a hardware implemented RSS engine 128 achieved close to 40 Gbit/s of network data transmission when the NIC has a capacity of 40 Gbit/s.
The MAC filter 156 can be configured to identify a virtual port ID 157 based on the MAC address received from the MAC extractor 155. In the illustrated embodiment, the MAC filter 156 can identify the virtual port ID 157 by comparing the received MAC address to records of port assignment 137 contained in the memory 124. In certain embodiments, the port assignment 137 can include a table with entries listing a virtual port ID with a corresponding MAC address, a default virtual port ID, or other suitable information. In other embodiments, the port assignment 137 can include an index, a state machine, or other suitable data structures.
As shown in
The process 200 can then include assigning packets in a virtual port of the network interface to a particular queue of the virtual port at stage 206. In certain embodiments, the packets are assigned to a particular queue based on a characteristic of communication of the packets. The characteristic of communication can include, for instance, a source IP address, a destination IP address, a source port, a destination port, and/or other suitable TCP parameters. In other embodiments, the packets can be assigned based on other suitable parameters or characteristics of the packets. The process 200 can then include cooperating with a core of a processor to process and forward the packets to the particular destination in the general destination at stage 208. An example operation for such processing is described above with reference to
As shown in
The process 210 can then include processing packets in the queue in response to the request at stage 214. In certain embodiments, processing the packets can include inspecting and retrieving the packets from the queue and executing one or more of enforcing communications security, performing network virtualization, translating network addresses, or maintaining a communication flow state with a core corresponding to the queue. In other embodiments, processing the packets can include performing other suitable functions with the core corresponding to the queue.
The process 210 can then include a decision stage 216 to determine whether the process 210 is complete. In one embodiment, the process 210 is complete when the queue contains no more packets. In other embodiments, the process 210 is complete when a user terminate the process 210 or under other suitable conditions. In response to determining that the process 210 is complete, the process 210 includes terminating operations at stage 218; otherwise, the process 210 reverts to processing additional packets at stage 214.
Depending on the desired configuration, the system memory 306 can be of any type including but not limited to volatile memory (such as RAM), non-volatile memory (such as ROM, flash memory, etc.) or any combination thereof. The system memory 306 can include an operating system 320, one or more applications 322, and program data 324. As shown in
The computing device 300 can have additional features or functionality, and additional interfaces to facilitate communications between basic configuration 302 and any other devices and interfaces. For example, a bus/interface controller 330 can be used to facilitate communications between the basic configuration 302 and one or more data storage devices 332 via a storage interface bus 334. The data storage devices 332 can be removable storage devices 336, non-removable storage devices 338, or a combination thereof. Examples of removable storage and non-removable storage devices include magnetic disk devices such as flexible disk drives and hard-disk drives (HDD), optical disk drives such as compact disk (CD) drives or digital versatile disk (DVD) drives, solid state drives (SSD), and tape drives to name a few. Example computer storage media can include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules, or other data. The term “computer readable storage media” or “computer readable storage device” excludes propagated signals and communication media.
The system memory 306, removable storage devices 336, and non-removable storage devices 338 are examples of computer readable storage media. Computer readable storage media include, but not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other media which can be used to store the desired information and which can be accessed by computing device 300. Any such computer readable storage media can be a part of computing device 300. The term “computer readable storage medium” excludes propagated signals and communication media.
The computing device 300 can also include an interface bus 340 for facilitating communication from various interface devices (e.g., output devices 342, peripheral interfaces 344, and communication devices 346) to the basic configuration 302 via bus/interface controller 330. Example output devices 342 include a graphics processing unit 348 and an audio processing unit 350, which can be configured to communicate to various external devices such as a display or speakers via one or more A/V ports 352. Example peripheral interfaces 344 include a serial interface controller 354 or a parallel interface controller 356, which can be configured to communicate with external devices such as input devices (e.g., keyboard, mouse, pen, voice input device, touch input device, etc.) or other peripheral devices (e.g., printer, scanner, etc.) via one or more I/O ports 358. An example communication device 346 includes a network controller 360, which can be arranged to facilitate communications with one or more other computing devices 362 over a network communication link via one or more communication ports 364.
The network communication link can be one example of a communication media. Communication media can typically be embodied by computer readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave or other transport mechanism, and can include any information delivery media. A “modulated data signal” can be a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media can include wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, radio frequency (RF), microwave, infrared (IR) and other wireless media. The term computer readable media as used herein can include both storage media and communication media.
The computing device 300 can be implemented as a portion of a small-form factor portable (or mobile) electronic device such as a cell phone, a personal data assistant (PDA), a personal media player device, a wireless web-watch device, a personal headset device, an application specific device, or a hybrid device that include any of the above functions. The computing device 300 can also be implemented as a personal computer including both laptop computer and non-laptop computer configurations.
From the foregoing, it will be appreciated that specific embodiments of the disclosure have been described herein for purposes of illustration, but that various modifications may be made without deviating from the disclosure. In addition, many of the elements of one embodiment may be combined with other embodiments in addition to or in lieu of the elements of the other embodiments. Accordingly, the technology is not limited except as by the appended claims.
This application is a non-provisional application of and claims priority to U.S. Provisional Application No. 62/430,482, filed on Dec. 6, 2016.
Number | Date | Country | |
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62430482 | Dec 2016 | US |