Distributed resource management method and system

Information

  • Patent Grant
  • 10313429
  • Patent Number
    10,313,429
  • Date Filed
    Monday, April 11, 2016
    8 years ago
  • Date Issued
    Tuesday, June 4, 2019
    5 years ago
Abstract
The present disclosure is drawn to methods and systems for resource enforcement in a distributed system. At least one first host of the system has an enforcement agent configured to trigger a master enforcement controller in response to the first host running a task requiring access to a distributed resource. The master enforcement controller obtains identification information regarding the distributed resource and transmits an enforcement command to other hosts of the distributed system involved in providing the distributed resource. The enforcement command is received by enforcement agents on each of the involved hosts and triggers a slave enforcement controller on each of the involved hosts. The slave enforcement controllers locally enforce a resource quota for the distributed resource.
Description
TECHNICAL FIELD

The present description relates to a framework and architecture for managing resources in a distributed system.


BACKGROUND OF THE ART

Resource allocation in a computing system is the assignment of available resources to various uses. Resource management is the scheduling of activities and the resources required by those activities while taking into consideration resource availability and timing. Resource management includes resource allocation and resource enforcement, which is ensuring that resource allocation is respected.


Resource management in systems of distributed resources is challenging and therefore, improvements are desired.


SUMMARY

The present disclosure is drawn to methods and systems for resource enforcement in a distributed system. At least one first host of the system has an enforcement agent configured to trigger a master enforcement controller in response to the first host running a task requiring access to a distributed resource. The master enforcement controller obtains identification information regarding the distributed resource and transmits an enforcement command to other hosts of the distributed system involved in providing the distributed resource. The enforcement command is received by enforcement agents on each of the involved hosts and triggers a slave enforcement controller on each of the involved hosts. The slave enforcement controllers locally enforce a resource quota for the distributed resource.


In accordance with a broad aspect, there is provided a method for resource enforcement in a distributed system having a plurality of hosts. A master enforcement controller on a first host of the plurality of hosts is triggered in response to the first host accessing a distributed resource of the distributed system. Identification information regarding the distributed resource is obtained by the master enforcement controller. The master enforcement controller transmits an enforcement command including the identification information to at least one second host of the plurality of hosts, the at least one second host being associated with the distributed resource, the enforcement command configured for triggering a slave enforcement controller on the at least one second host for locally enforcing a resource quota.


In some embodiments, obtaining identification information comprises determining an accessing mechanism for the distributed resource. In some embodiments, obtaining identification information comprises identifying the at least one second host by determining which ones of the plurality of hosts are involved in providing the distributed resource.


In some embodiments, transmitting the enforcement command comprises transmitting to two or more hosts of the plurality of hosts.


In some embodiments, the enforcement command further comprises the resource quota for each of the two or more hosts.


In some embodiments, the method further comprises dynamically adjusting the resource quota based on access to the distributed resource by the first host. In some embodiments, dynamically adjusting the resource quota comprises setting different resource quotas for each of the two or more hosts.


In some embodiments, the method further comprises receiving the enforcement command from another one of the plurality of hosts of the distributed system; and triggering the slave enforcement controller on the first host.


In some embodiments, the enforcement command includes an adjusted resource quote.


In accordance with another aspect, there is provided a host in a distributed system having a plurality of hosts. The host comprises a processing unit and a non-transitory memory communicatively coupled to the processing unit. The memory comprises computer-readable program instructions executable by the processing unit for triggering a master enforcement controller on the host in response to the host accessing a distributed resource of the distributed system; obtaining, by the master enforcement controller, identification information regarding the distributed resource; and transmitting an enforcement command including the identification information to at least one other host of the plurality of hosts, the at least one other host being associated with the distributed resource, the enforcement command configured for triggering a slave enforcement controller on the at least one other host for locally enforcing a resource quota.


In some embodiments, obtaining identification information comprises determining an accessing mechanism for the distributed resource.


In some embodiments, obtaining identification information comprises identifying the at least one other host by determining which ones of the plurality of hosts are involved in providing the distributed resource.


In some embodiments, transmitting the enforcement command comprises transmitting to two or more hosts of the plurality of hosts.


In some embodiments, the enforcement command further comprises the resource quota for each of the two or more hosts.


In some embodiments, the processing unit is further executable for dynamically adjusting the resource quota based on access to the distributed resource by the host.


In some embodiments, dynamically adjusting the resource quota comprises setting different resource quotas for each of the two or more hosts.


In some embodiments, the processing unit is further executable for receiving the enforcement command from another one of the plurality of hosts of the distributed system; and triggering the slave enforcement controller on the host.


In some embodiments, the enforcement command includes an adjusted resource quote.


In accordance with another broad aspect, there is provided a distributed resource management system comprising a plurality of hosts, at least one of the plurality of hosts comprising an enforcement agent, the enforcement agent configured for locally triggering a master enforcement controller in response to access of a distributed resource by a corresponding host, the master enforcement controller configured for obtaining identification information regarding the distributed resource and transmitting an enforcement command with the identification information to at least one other host associated with the distributed resource, the enforcement agent also configured for locally triggering a slave enforcement controller upon receipt of the enforcement command from another one of the plurality of hosts, the slave enforcement controller configured for locally enforcing a resource quota.


In some embodiments, each one of the plurality of hosts comprise the enforcement configured for locally triggering the master enforcement controller and the slave enforcement controller.





BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings, in which:



FIG. 1 is a block diagram of an example distributed system;



FIG. 2 is a block diagram of a first example host of the distributed system of FIG. 1;



FIG. 3 is a block diagram of a second example host of the distributed system of FIG. 1;



FIG. 4 is a block diagram of a third example host of the distributed system of FIG. 1; and



FIG. 5 is a flowchart of an example method for resource enforcement of the distributed system of FIG. 1.





It will be noted that throughout the appended drawings, like features are identified by like reference numerals.


DETAILED DESCRIPTION

Referring to FIG. 1, there is illustrated a distributed system 100, comprising a plurality of hosts 1021, 1022, 1023 (collectively referred to as 102). The hosts 102 are hardware systems which either host an application task or host a distributed resource. The hosts 102 are interconnected and more than one of the hosts 102 has the ability to be operating at the same time. The hosts 102 can send data and messages to each other through communication links 104. The hosts 102 may be any one of one or more servers, one or more computers, one or more storage mediums, and one or more networks. The system 100 may be composed of different types of hosts. For example, host 1021 is a server, host 1022 is a computer, and host 1023 is a network of computers. Other combinations are also possible.


The system 100 can be arranged according to any one of the following architectures: host-based hierarchy, decentralized stand-alone, peer-to-peer Local Access Network (LAN)-based, hybrid enterprise-wide, client-server, and Internet-centric. At least one distributed service is provided across at least two of the hosts 102, and at least one of the hosts 102 can run a task. Examples of tasks are High Performance Computing (HPC) batch jobs, Message Passing Interface (MPI), serial batches, real-time analytics, elastic applications, long running services, virtual machines, and task containers. Examples of distributed resources are distributed file systems, virtualized file systems, distributed databases, virtualized networks, and distributed cache.


At least one first host 1021 of the plurality of hosts 102 in the distributed system 100 is configured for distributed resource enforcement across the system 100 when the first host 1021 runs a task that accesses a distributed resource. At least one second host 1022 of the plurality of hosts 102 in the distributed system 100 is configured for distributed resource enforcement across the system 100 when the first host 1021 accesses a distributed resource to which the second host 1022 is associated, i.e. the second host 1022 is involved in providing the distributed resource accessed by the first host 1021.



FIG. 2 is an example embodiment of first host 1021, which accesses the distributed resource. Host 1021 includes a processor 2021 coupled to a memory 2041. Memory 2041, accessible by processor 2021, receives and stores data. Memory 2041 may be random-access memory (RAM), read-only memory (ROM), optical-disc-based read-only memory, electro-optical memory, magneto-optical memory, erasable programmable read-only memory (EPROM), electrically-erasable programmable read-only memory (EEPROM), Ferroelectric RAM (FRAM), and the like. Processor 2021 accesses the memory 2041 to retrieve data. Processor 2021 may be any device that can perform operations on data. Examples include any type of general-purpose microprocessor or microcontroller, a digital signal processing (DSP) processor, an integrated circuit, a field programmable gate array (FPGA), a reconfigurable processor, or any combination thereof. Memory 2041 has stored thereon computer-readable program instructions executable by processor 2021.


An enforcement agent 2061 is provided on first host 1021 and is operatively coupled to a master enforcement controller 2081. Enforcement agent 2061 may be running an application task and/or a distributed resource on first host 1021 and is configured to trigger master enforcement controller 2081 in response to the first host accessing a distributed resource of the system 100. Therefore, master enforcement controller 2081 is started by enforcement agent 2061 on first host 1021. Master enforcement controller 2081 obtains identification information regarding the distributed resource accessed by first host 1021. Master enforcement controller 2081 then transmits an enforcement command with the identification information to at least the second host 1022 in the distributed system 100. If additional ones of the plurality of hosts 102 are also associated with the accessed distributed resource, then the enforcement command is transmitted to all of the associated hosts 102.



FIG. 3 is an example embodiment of second host 1022, associated with the accessed distributed resource. Host 1022 includes a processor 2022 coupled to a memory 2042. Processor 2022 can access memory 2042 to store and retrieve data. Memory 2042 may be a main memory, such as a high speed Random Access Memory (RAM), or an auxiliary storage unit, such as a hard disk, a floppy disk, or a magnetic tape drive, or any combination thereof. Memory 2042 may be any other type of memory, such as a Read-Only Memory (ROM), or optical storage media such as a videodisc and a compact disc. Processor 2022 accesses memory 2042 to retrieve data. Processor 2022 may be any device that can perform operations on data. Examples are a central processing unit (CPU), a front-end processor, a microprocessor, and a network processor. Memory 2042 has stored thereon computer-readable program instructions executable by processor 2022. Note that processor 2021 and processor 2022 do not have to be the same type of processor. Similarly, memory 2041 and memory 2042 do not have to be the same type of memory.


An enforcement agent 2062 is provided on second host 1022 and is operatively coupled to a slave enforcement controller 3062. Enforcement agent 2062 runs the distributed resource accessed by first host 1021 and is configured to trigger slave enforcement controller 3062 in response to receipt of the enforcement command from first host 1021. Therefore, enforcement agent 2062 starts slave enforcement controller 3062 on second host 1022. Slave enforcement controller 3062 conducts local resource enforcement according to a resource quota.


The resource quota can be provided to second host 1022 by any one of the hosts 102 in the distributed system 100, or by another entity that acts as a master scheduler for setting an initial resource quota. In some embodiments, master enforcement controller 2081 is configured to dynamically adjust the resource quota based on access to the distributed resource by first host 1021. The adjusted resource quota is then transmitted from master enforcement controller 2081 to slave enforcement controller 3062, either as part of the identification information or separately therefrom. In some embodiments, the initial resource quota is transmitted from master enforcement controller 2081 to slave enforcement controller 3062, either as part of the identification information or separately therefrom, and the initial resource quota is iteratively adapted and retransmitted from master enforcement controller 2081 to slave enforcement controller 3062 as first host 1021 continues to perform the task involving access to the distributed resource.


When more than one of the hosts 102 is involved in providing the distributed resource, master enforcement controller 2081 transmits the enforcement command to each one of hosts 102 involved. The enforcement command will cause a local enforcement agent on each one of the involved hosts 102 to trigger a local slave enforcement controller. In some embodiments, master enforcement controller 2081 provides each one of the involved hosts 102 with a different resource quota, as a function of the specific needs of each involved host 102.


In some embodiments, at least one host 1023 has an enforcement agent 2063 configured for selectively triggering a local master enforcement controller 2083 and a local slave enforcement controller 3063, as illustrated in FIG. 4. Master enforcement controller 2083 is triggered when host 1023 accesses a distributed resource of the system 100. Slave enforcement controller 3063 is triggered when an enforcement command is received from another one of the hosts 102, such as host 1021. Host 1023 can therefore become a master or a slave, depending on the activity in the distributed system 100. In some embodiments, all hosts 102 are configured to be both masters and slaves.


Referring to FIG. 5, there is illustrated a method for resource enforcement of the distributed system 100, as performed, for example, by host 1023. At step 502, master enforcement controller 2083 is triggered on host 1023 in response to host 1023 running an access task that requires accessing a distributed resource of the system 100.


At step 504, identification information is obtained by master enforcement controller 2083 regarding the distributed resource. In some embodiments, obtaining the identification information involves identifying which distributed resource is to be accessed. For example, identification information such as Transmission Control Protocol (TCP) connections, Internet Protocol (IP) addresses, and Ports may be obtained. The access task may require access to multiple distributed resources. In some embodiments, obtaining the identification information also involves determining which ones of the hosts 102 are involved in providing the one or more distributed resources required by the access task. These may be identified by, for example, IP address. Identification information may include one or more of connections, flows, and/or requests between the distributed resource and the access task running on host 1023. In some embodiments, identification information includes process ID, connection socket ID, and port ID.


At step 506, the master enforcement controller 2083 transmits an enforcement command to other hosts 102 of the distributed system 100 in order to locally enforce, on each recipient host 102, a resource quota associated with the distributed resource. The enforcement command is sent to all hosts 102 involved in the one or more distributed resource required for the access task run by host 1023. The enforcement command includes the identification information obtained by the master enforcement controller 2083 in step 504, and is received by an enforcement agent of a corresponding host. The enforcement command is configured to trigger a slave enforcement controller on each corresponding host, for locally enforcing the resource quota. For example, local resource enforcement may involve limiting a corresponding TCP connection rate.


In some embodiments, the master enforcement controller 2083 continues to monitor the task performed by host 1023, as per step 508, and will send updated information to involved hosts 102 as required, as per step 510. For example, if the requirements regarding the distributed resource change, an adjusted resource quota is provided to each of the involved hosts 102.


The change in requirements may be detected by the master enforcement controller 2083 or by any of the slave enforcement controllers of corresponding hosts 102. Indeed, each slave enforcement controller can monitor connections, requests, flow status, and usage. For example, if host 1021 and host 1022 each enforce a connection flow rate of 45 MB/s for a target bandwidth of 90 MB/s, and the connection to host 1022 is terminated, slave enforcement controller 3062 detects the terminated connection and transmits the information to master enforcement controller 2083. Master enforcement controller 2083 can then adjust the resource quota of host 1021 to 90 MB/s. Alternatively, master enforcement controller 2083 detects the terminated connection and transmits an adjusted resource quota to host 1021. In some embodiments, an adjusted resource quota is transmitted from the master enforcement controller 2083 to one or more other hosts 102 for reasons other than a terminated connection.


In some embodiments, step 508 involves determining that a new distributed resource is needed for the access task. Sending updated information 510 then involves identifying any additional hosts 102 involved in the new distributed resource and triggering slave enforcement controllers on each of the additional hosts 102 by repeating steps 502, 504, 506.


When the access task is completed, the method proceeds to step 512 and ends.


Note that each one of the hosts 102 may have more than one master enforcement controller associated with an enforcement agent. The hosts 102 may also have more than one slave enforcement controller associated with an enforcement agent. For example, each task of host 1023 may be assigned one master enforcement controller and multiple slave controllers, so that when multiple tasks are running on host 1023, multiple enforcement controllers are also running on host 1023.


Each computer program described herein may be implemented in a high level procedural or object oriented programming or scripting language, or a combination thereof, to communicate with a computer system. Alternatively, the programs may be implemented in assembly or machine language. The language may be a compiled or interpreted language. Each such computer program may be stored on a storage media or a device, for example a ROM, a magnetic disk, an optical disc, a flash drive, or any other suitable storage media or device. The computer program may be readable by a general or special-purpose programmable computer for configuring and operating the computer when the storage media or device is read by the computer to perform the procedures described herein. Embodiments of the system may also be considered to be implemented by way of a non-transitory computer-readable storage medium having a computer program stored thereon. The computer program may comprise computer-readable instructions which cause a computer, or more specifically the at least one processing unit of the computer, to operate in a specific and predefined manner to perform the functions described herein.


Computer-executable instructions may be in many forms, including program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Typically the functionality of the program modules may be combined or distributed as desired in various embodiments.


Various aspects of the present distributed system 100 may be used alone, in combination, or in a variety of arrangements not specifically discussed in the embodiments described in the foregoing and is therefore not limited in its application to the details and arrangement of components set forth in the foregoing description or illustrated in the drawings. For example, aspects described in one embodiment may be combined in any manner with aspects described in other embodiments. Although particular embodiments have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects. The appended claims are to encompass within their scope all such changes and modifications.

Claims
  • 1. A method for distributed resource enforcement in a distributed computing system comprising a plurality of hosts, the method comprising: in response to an enforcement agent, provided on a first host of the plurality of hosts, running a task that requires access to a distributed resource of the distributed computing system, designating a master enforcement controller to obtain identification information regarding the distributed resource, wherein at least two of the plurality of hosts are involved in providing the distributed resource and include the first host;transmitting, from the master enforcement controller provided on the first host, a first enforcement command including the identification information to at least one host of the at least two of the plurality of hosts involved in providing the distributed resource, the first enforcement command starting a slave enforcement controller provided on the at least one host to locally enforce a resource quota for the at least one host;receiving, at the master enforcement controller provided on the first host, a second enforcement command from another one of the plurality of hosts of the distributed computing system, the second enforcement command including an adjusted resource quota; andin response to receipt of the second enforcement command, designating the slave enforcement controller provided on the first host to locally enforce the adjusted resource quota for the first host.
  • 2. The method of claim 1, wherein the task comprises one of a High Performance Computing (HPC) batch job, a Message Passing Interface (MPI), a serial batch, real-time analytics, an elastic application, a long running service, a virtual machine, and a task container, and wherein the distributed resource comprises one of a distributed file system, a virtualized file system, a distributed database, a virtualized network, and a distributed cache.
  • 3. The method of claim 2, wherein obtaining identification information comprises identifying the at least one host by determining which ones of the at least two of the plurality of hosts are involved in providing the distributed resource.
  • 4. The method of claim 1, wherein transmitting the first enforcement command comprises transmitting the first enforcement command to two or more hosts of the at least two of the plurality of hosts.
  • 5. The method of claim 4, wherein the first enforcement command further comprises the resource quota for each of the two or more hosts.
  • 6. The method of claim 5, further comprising dynamically adjusting the resource quota based on access to the distributed resource by the first host.
  • 7. The method of claim 6, wherein dynamically adjusting the resource quota comprises setting different resource quotas for each of the two or more hosts.
  • 8. A host in a distributed computing system having a plurality of hosts, the host comprising: a processing unit; anda non-transitory memory communicatively coupled to the processing unit and comprising computer readable program instructions executable by the processing unit for:in response to an enforcement agent, provided on a first host of the plurality of hosts, running a task that requires access to a distributed resource of the distributed computing system, designating a master enforcement controller to obtain identification information regarding the distributed resource, wherein at least two of the plurality of hosts are involved in providing the distributed resource and include the first host;transmitting, from the master enforcement controller provided on the first host, an enforcement command including the identification information to at least one host of the at least two of the plurality of hosts involved in providing the distributed resource, the enforcement command starting a slave enforcement controller provided on the at least one host to locally enforce a resource quota for the at least one host;receiving, at the master enforcement controller provided on the first host, a second enforcement command from another one of the plurality of hosts of the distributed computing system, the second enforcement command including an adjusted resource quota; andin response to receipt of the second enforcement command, designating the slave enforcement controller provided on the first host to locally enforce the adjusted resource quota for the first host.
  • 9. The host of claim 8, wherein the task comprises one of a High Performance Computing (HPC) batch job, a Message Passing Interface (MPI), a serial batch, real-time analytics, an elastic application, a long running service, a virtual machine, and a task container, and wherein the distributed resource comprises one of a distributed file system, a virtualized file system, a distributed database, a virtualized network, and a distributed cache.
  • 10. The host of claim 9, wherein obtaining identification information comprises identifying the at least one host by determining which ones of the at least two of the plurality of hosts are involved in providing the distributed resource.
  • 11. The host of claim 8, wherein transmitting the first enforcement command comprises transmitting the first enforcement command to two or more hosts of the at least two of the plurality of hosts.
  • 12. The host of claim 11, wherein the first enforcement command further comprises the resource quota for each of the two or more hosts.
  • 13. The host of claim 12, wherein the processing unit is further executable for dynamically adjusting the resource quota based on access to the distributed resource by the first host.
  • 14. The host of claim 13, wherein dynamically adjusting the resource quota comprises setting different resource quotas for each of the two or more hosts.
  • 15. A distributed computing system comprising a plurality of hosts, at least two of the plurality of hosts are involved in providing a distributed resource, at least one first host of the plurality of hosts running a task that requires access to the distributed resource and comprising an enforcement agent, the at least two of the plurality of hosts involved in providing the distributed resource including the at least one first host, the enforcement agent configured for locally designating a master enforcement controller on the at least one first host to obtain identification information regarding the distributed resource in response to the enforcement agent requiring access to the distributed resource and transmitting a first enforcement command with the identification information to the at least one host of the two of the plurality of hosts involved in providing the distributed resource, the first enforcement command designating a slave enforcement controller provided on the at least one host upon receipt of a second enforcement command including an adjusted resource quota from another one of the plurality of hosts to locally enforce the adjusted resource quota on the at least one host.
  • 16. The distributed computing system of claim 15, wherein each one of the plurality of hosts comprise an enforcement agent configured for locally designating the master enforcement controller and the slave enforcement controller.
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Related Publications (1)
Number Date Country
20170295220 A1 Oct 2017 US