CN116431336A

CN116431336A - Page cache limiting method, page cache limiting system, electronic equipment and storage medium

Info

Publication number: CN116431336A
Application number: CN202310281790.4A
Authority: CN
Inventors: 郝信; 徐宇; 王荣巍
Original assignee: Alibaba Cloud Computing Ltd
Current assignee: Alibaba Cloud Computing Ltd
Priority date: 2023-03-17
Filing date: 2023-03-17
Publication date: 2023-07-14

Abstract

One or more embodiments of the present specification provide a page buffer limiting method, system, electronic device, and storage medium. The method comprises the following steps: determining a target system resource management and control component which is preconfigured and needs to limit page cache, and determining a limit threshold value and a memory recovery mode which are preconfigured for the target system resource management and control component and aim at page cache; detecting whether the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold; and if the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold, performing memory reclamation on the page cache of the target system resource management and control component according to the memory reclamation mode. Through the mode, page cache limitation can be performed based on granularity of the system resource management and control component or granularity of the operating system, the use efficiency of the memory of the container is improved, occurrence of OOM (on-line memory) is further reduced, and user experience is improved.

Description

Page cache limiting method, page cache limiting system, electronic equipment and storage medium

Technical Field

One or more embodiments of the present disclosure relate to the field of computer technology, and in particular, to a method, a system, an electronic device, and a storage medium for limiting page buffering.

Background

With the advent of the cloud-grown era, more and more users began using containers. Containers (containers) are a kernel virtualization technology of an operating system, and may be used to isolate processes, and may allocate system resources, such as CPUs, memory, disk I/os, and the like, for each process. In practical application, the system resource accounting and the resource usage of each process can be limited through a kernel function system resource management component s (Linux control group).

Containers deployed in cloud computing environments, available memory capacity is typically limited; once the Memory usage of the container exceeds the limit, an ook (Out of Memory) may occur, and the ook killer process may select at least one process "kill" from the system and release all Memory pages occupied by the process.

If the killed process is a core service process, service performance jitter may be caused, and user experience is seriously affected, so that occurrence of an OOM condition needs to be avoided as much as possible.

Disclosure of Invention

The application provides a page cache limiting method, which is applied to a terminal loaded with an operating system, and comprises the following steps:

Determining a target system resource management and control component which is preconfigured and needs to limit page cache, and determining a limit threshold value and a memory recovery mode which are preconfigured for the target system resource management and control component and aim at page cache;

detecting whether the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold;

and if the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold, performing memory reclamation on the page cache of the target system resource management and control component according to the memory reclamation mode.

Optionally, a memory resource management and control structure body created for the target system resource management and control component includes a limit function switch variable, a limit threshold variable and a memory reclamation mode variable;

the determining a pre-configured target system resource management and control component needing to limit page cache comprises the following steps:

determining that the target system resource management and control component is a system resource management and control component which is pre-configured and needs to limit page cache according to the first value of the limit function switch variable included in the memory resource management and control structure; or determining that the target system resource management and control component is a preconfigured system resource management and control component which does not need to limit page cache according to the fact that the limit function switch variable included in the memory resource management and control structure body is a second value;

The determining a limit threshold for page cache preconfigured for the target system resource management component includes:

determining the value of a limiting threshold variable included in the memory resource management and control structure body as a limiting threshold for page cache, which is preconfigured for the target system resource management and control component;

the determining a memory recovery mode preconfigured for the target system resource management and control component comprises the following steps:

according to the memory recovery mode variable included in the memory resource management and control structure body is a third numerical value, determining that a memory recovery mode preset for the target system resource management and control component is an asynchronous recovery mode; or determining that the memory recovery mode preconfigured for the target system resource management and control component is a synchronous recovery mode according to the fact that the memory recovery mode variable included in the memory resource management and control structure body is a fourth numerical value.

Optionally, the memory recovery mode is a synchronous recovery mode; according to the memory recycling mode, performing memory recycling on the page cache of the target system resource management and control component, including:

scanning a page cache of the target system resource management and control component, and synchronously recovering unmapped file pages of the target system resource management and control component;

If the memory capacity occupied by the page cache of the target system resource management and control component still exceeds the limit threshold, rescanning the page cache of the target system resource management and control component, and synchronously recycling unmapped file pages of the target system resource management and control component until the memory capacity occupied by the page cache of the target system resource management and control component does not exceed the limit threshold;

and if the scanning times of the page caches of the target system resource management and control components exceed a first threshold, synchronously recycling the mapping file pages of the target system resource management and control components.

Optionally, the memory recovery mode is an asynchronous recovery mode; according to the memory recycling mode, performing memory recycling on the page cache of the target system resource management and control component, including:

scanning a page cache of the target system resource management and control component, and asynchronously recovering clean pages of the target system resource management and control component; the clean page is a memory page in which cached data is written back to a storage medium; the clean page comprises an unmapped file page and a mapped file page;

If the memory capacity occupied by the page cache of the target system resource management and control component still exceeds the limit threshold, rescanning the page cache of the target system resource management and control component, and asynchronously recycling the clean page of the target system resource management and control component until the memory capacity occupied by the page cache of the target system resource management and control component does not exceed the limit threshold;

if the scanning times of the page cache of the target system resource management and control component exceeds a second threshold value, asynchronous recovery of dirty pages of the target system resource management and control component is allowed; the dirty page is a memory page in which cached data is not written back to the storage medium.

scanning a page cache of the target system resource management and control component, determining memory pages needing to be asynchronously recovered, and asynchronously recovering the memory pages needing to be asynchronously recovered;

in response to detecting that available CPU resources of an operating system are insufficient, CPU resources which are originally used for asynchronous recovery of memory pages to be asynchronously recovered by a memory recovery process are scheduled to other processes except the memory recovery process.

Optionally, the method further comprises:

if the memory capacity occupied by the page cache of the target system resource management and control component does not exceed the limit threshold, detecting whether the memory capacity occupied by the page cache of the parent system resource management and control component of the target system resource management and control component exceeds the limit threshold;

and if the memory capacity occupied by the page cache of the parent system resource management and control component exceeds the limit threshold, performing memory reclamation on the page cache of the parent system resource management and control component according to a memory reclamation mode pre-configured for the parent system resource management and control component.

Optionally, the determining a preconfigured target system resource management component needing to limit page buffering includes:

and in response to detecting that the available memory resources of the operating system are insufficient, determining a pre-configured target system resource management component needing to limit page cache from at least one system resource management component for performing memory resource management on the operating system.

The application also provides a page buffer limiting device, which is applied to a terminal loaded with an operating system, and comprises:

the system comprises a determining unit, a target system resource management and control component, a limiting threshold value and a memory recycling mode, wherein the target system resource management and control component is preconfigured and needs to limit page cache;

The first detection unit is used for detecting whether the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold;

and the first recovery unit is used for carrying out memory recovery on the page cache of the target system resource management and control component according to the memory recovery mode if the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold.

The application also provides a page cache limiting system which is used for realizing the method.

The application also provides electronic equipment, which comprises a communication interface, a processor, a memory and a bus, wherein the communication interface, the processor and the memory are connected with each other through the bus;

the memory stores machine readable instructions and the processor performs the method by invoking the machine readable instructions.

The present application also provides a machine-readable storage medium storing machine-readable instructions that, when invoked and executed by a processor, implement the above-described methods.

Through the above embodiment, by opening the page buffer memory limiting function for the target system resource management and control component and pre-configuring the limiting threshold value and the memory reclamation mode for the page buffer memory for the target system resource management and control component, when detecting that the memory capacity occupied by the page buffer memory of the target system resource management and control component exceeds the pre-configured limiting threshold value, the memory reclamation can be performed for the page buffer memory of the target system resource management and control component according to the pre-configured memory reclamation mode. Therefore, page cache restriction can be performed based on the granularity of the system resource management and control component or the granularity of the operating system, the utilization efficiency of the memory of the container is improved, the occurrence of OOM (on-hook memory) condition can be reduced, and the user experience is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings that are needed in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present disclosure, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart illustrating a method of page cache restriction in accordance with an exemplary embodiment;

FIG. 2 is a flow chart illustrating another page cache restriction method in accordance with an exemplary embodiment;

FIG. 3 is a schematic diagram of an electronic device with a page buffer limiting device according to an exemplary embodiment;

FIG. 4 is a block diagram illustrating a page cache limiting device in accordance with an exemplary embodiment.

Detailed Description

In order to make the technical solutions in the present specification better understood by those skilled in the art, the technical solutions in the embodiments of the present specification will be clearly and completely described below with reference to the drawings in the embodiments of the present specification, and it is obvious that the described embodiments are only some embodiments of the present specification, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are intended to be within the scope of the present disclosure.

It should be noted that: in other embodiments, the steps of the corresponding method are not necessarily performed in the order shown and described in this specification. In some other embodiments, the method may include more or fewer steps than described in this specification. Furthermore, individual steps described in this specification, in other embodiments, may be described as being split into multiple steps; while various steps described in this specification may be combined into a single step in other embodiments.

With the advent of the cloud-grown era, more and more users began using containers. Containers (containers) are a kernel virtualization technology of an operating system, and may be used to isolate processes, and may allocate system resources, such as CPUs, memory, disk I/os, and the like, for each process.

Currently, mainstream operating systems are all provided with a system resource management and control component, and resources used by processes/threads can be isolated, managed, recorded and the like through the system resource management and control component. For example, taking a Linux system as an example, a system resource management component carried by the Linux system may be a cgroup (Linux control group).

In practical applications, the memory capacity occupied by the file page cache is found to be a significant fraction of the total memory capacity of the container. The file page buffer is to buffer data read from a storage medium such as a disk or a file system into a system memory page; a File Page (File-cached Page) may include disk data (Buffer) cached by the kernel and File data (Cache) cached by the kernel; memory pages (pages) are typically the basic unit of memory management by the operating system kernel.

In view of this, the present disclosure is directed to providing a page buffer limiting function, which can be used to limit the memory capacity that can be occupied by the page buffer of each system resource management and control component, so as to reduce the occurrence of the OOM condition.

When the method is realized, a target system resource management and control component which is preconfigured and needs to limit page cache can be determined, a limit threshold value for page cache which is preconfigured for the target system resource management and control component is determined, and a memory recycling mode which is preconfigured for the target system resource management and control component is determined; further, it may be detected whether the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold; if the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold, memory reclamation can be performed on the page cache of the target system resource management and control component according to the memory reclamation mode.

Therefore, in the technical scheme in the specification, by starting the page cache limiting function for the target system resource management and control component and pre-configuring the limiting threshold value and the memory recycling mode for the page cache for the target system resource management and control component, when the memory capacity occupied by the page cache of the target system resource management and control component is detected to exceed the pre-configured limiting threshold value, the memory recycling can be performed for the page cache of the target system resource management and control component according to the pre-configured memory recycling mode. Therefore, page cache restriction can be performed based on the granularity of the system resource management and control component or the granularity of the operating system, the utilization efficiency of the memory of the container is improved, the occurrence of OOM (on-hook memory) condition can be reduced, and the user experience is improved.

The following describes the present application through specific embodiments and in connection with specific application scenarios. In order to facilitate a better understanding of the technical solution in the present specification by those skilled in the art, the following description uses the cgroup carried by the Linux system as an example, which is not meant to limit the present specification in particular.

Referring to fig. 1, fig. 1 is a flowchart illustrating a page buffer limiting method according to an exemplary embodiment. The method can be applied to the terminal with the Linux system.

In the present specification, the terminal device may specifically include one server on which the Linux system is mounted, or a server cluster formed by a plurality of servers, or may include a client-side network device on which the Linux system is mounted, which is not particularly limited in the present specification.

As shown in fig. 1, the page buffer limiting method may perform the steps of:

step 102: determining a target system resource management and control component which is preconfigured and needs to limit page cache, and determining a limit threshold value and a memory recycling mode which are preconfigured for the target system resource management and control component and aim at page cache.

In step 102, the memory reclamation method may include an asynchronous reclamation method or a synchronous reclamation method; the asynchronous recovery mode can refer to an asynchronous execution memory recovery mode which does not block an original process; the synchronous recovery mode may refer to a memory recovery mode which is executed synchronously and can block an original process.

For example, it may be determined that the target cgroup that needs to limit the page cache is preconfigured as node a, that the limit threshold for the page cache that is preconfigured as node a is n1, and that the memory reclamation mode that is preconfigured as node a is a synchronous reclamation mode.

For another example, the target cgroup that needs to limit the page cache that is preconfigured may be determined to be the node B, the limit threshold for the page cache that is preconfigured for the node B may be determined to be n2 (n 1 and n2 may be different), and the memory reclamation manner that is preconfigured for the node B may be determined to be an asynchronous reclamation manner.

In step 102, the target system resource management component may be any system resource management component that has turned on the page cache restriction function. For example, if the page cache limiting function is turned on for each of the node a, the node B, and the node C, the above nodes may be traversed in sequence, and the traversed node is determined as the target cgroup, and the technical solution in the present specification is executed for the target cgroup.

It should be noted that if only the page cache restriction function of a part of the system resource management and control components is started, page cache restriction can be performed based on granularity of the system resource management and control components; if the global page cache restriction function or the page cache restriction function of all system resource management components is enabled, page cache restriction may be performed based on operating system granularity.

In one embodiment shown, the page cache limit function may be dynamically controlled by a user mode switch without requiring redeployment of the compilation.

For example, the following interfaces may be provided to the user: (1) The interface may be configured to whether to start the page cache restriction function of the cgroup, where the value of the interface may be 0 or 1, where the value of the interface may represent that the page cache restriction function of the cgroup is disabled when the value of the interface is 0, and the value of the interface may represent that the page cache restriction function of the cgroup is started when the value of the interface is 1; (2) memory. Pagecache_limit. Size, which may be used to configure the cgroup's limit threshold for page cache; (3) The memory_limit_sync may be used to configure whether to turn on the asynchronous reclamation function of the cgroup, where a value of 0 may indicate that the asynchronous reclamation function is disabled (i.e., the synchronous reclamation function is turned on), and a value of 1 may indicate that the asynchronous reclamation function is turned on.

When the method is implemented, the memory resource management structure body created by the target system resource management component can comprise a limit function switch variable, a limit threshold variable and a memory recycling mode variable.

In this case, the determining a preconfigured target system resource management component that needs to limit page buffering may specifically include: determining that the target system resource management and control component is a system resource management and control component which is pre-configured and needs to limit page cache according to the first value of the limit function switch variable included in the memory resource management and control structure; or determining that the target system resource management and control component is a preconfigured system resource management and control component which does not need to limit page cache according to the fact that the limit function switch variable included in the memory resource management and control structure body is a second value.

The determining a limit threshold for page cache preconfigured for the target system resource management component may specifically include: and determining the value of a limiting threshold variable included in the memory resource management and control structure body as a limiting threshold for page cache, which is preconfigured for the target system resource management and control component.

The determining a memory recovery mode preconfigured for the target system resource management and control component specifically may include: according to the memory recovery mode variable included in the memory resource management and control structure body is a third numerical value, determining that a memory recovery mode preset for the target system resource management and control component is an asynchronous recovery mode; or determining that the memory recovery mode preconfigured for the target system resource management and control component is a synchronous recovery mode according to the fact that the memory recovery mode variable included in the memory resource management and control structure body is a fourth numerical value.

For example, the target cgroup is node a, and the structure body "struct memcg" created for node a may include a limit function switch variable "enable", a limit threshold variable "size", and a memory reclamation mode variable "sync"; where "enable" and "sync" may be boolean type variables and "size" may be integer type variables. For the node a, according to the limiting function switch variable "enable=1", the limiting threshold variable "size=n1" and the memory reclamation mode variable "sync=0", it may be determined that the page buffer limitation needs to be performed for the node a, the limiting threshold value for the page buffer preconfigured for the node a is n1, and the memory reclamation mode preconfigured for the node a is a synchronous reclamation mode.

For another example, the target cgroup may be a node B, and according to a limit function switch variable "enable=1", a limit threshold variable "size=n2", and a memory reclamation mode variable "sync=1", it may be determined that the page cache is required to be limited for the node a, a limit threshold value for the page cache preconfigured for the node a is n2, and a memory reclamation mode preconfigured for the node a is an asynchronous reclamation mode. The structure body 'struct memcg' created for the node B may also include 'struct work', and a task queue for performing asynchronous reclamation is created for the node B.

In the embodiment shown above, the first value is 1, the second value is 0, the third value is 1, and the fourth value is 0, which is merely an exemplary description and does not limit the present specification in any way.

In the above-described embodiment, the page cache restriction function based on the cgroup granularity can be realized by adding the restriction function switch variable "enable", the restriction threshold variable "size" and the memory reclamation method variable "sync" to the "struct memcg", but the memory capacity occupied by the "struct memcg" itself increases. In the related art, a variable (such as pagecount) with hundreds of bytes is generally added in a struct memcg to monitor and manage the use condition of the memory; in this specification, the limit function switch variable and the memory recovery mode variable may be boolean type variables, and the limit threshold variable may be integer type variables, so that only more than ten bytes may be occupied, so that the structure memcg itself is prevented from occupying excessive memory capacity, and thus, when the page cache is limited, memory resources consumed for creating the structure memcg are saved, the code workload of a developer is reduced, the number of interfaces required for realizing the page cache limiting function is reduced, and the use mode of a user is simplified.

In one embodiment shown, the step 102 may be triggered by an "out-of-memory event". In this case, the determining a preconfigured target system resource management component that needs to limit page buffering may specifically include: in response to detecting that the available memory resources of the operating system are insufficient, determining a pre-configured target system resource management component requiring limiting page buffering from at least one system resource management component for performing memory resource management on the operating system.

For example, in response to detecting that available memory resources of the Linux system are insufficient, each cgroup of the opened page buffer restriction function may be determined as a target cgroup, and the technical solution in the present specification is executed for the target cgroup.

In some possible embodiments, the operating system is loaded with a plurality of containers isolated from each other; specifically, in response to detecting that the available memory resources of any container carried by the operating system are insufficient, a target system resource management component which is configured in advance and needs to limit page cache can be determined from at least one system resource management component for performing memory resource management on the container.

Step 104: and detecting whether the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold.

Step 106: and if the memory capacity occupied by the page cache of the target system resource management and control component exceeds the limit threshold, performing memory reclamation on the page cache of the target system resource management and control component according to the memory reclamation mode.

For example, the target cgroup may be node a, and after determining that the limit threshold for the page buffer preconfigured for node a is n1, it may be detected whether the memory capacity nA currently occupied by the page buffer of node a exceeds the limit threshold n1; if nA > n1, then synchronous reclamation can be performed for the page cache of node A according to a memory reclamation mode pre-configured for node A.

For another example, the target cgroup may be the node B, and after determining that the limit threshold for the page buffer preconfigured for the node B is n2, it may be detected whether the memory capacity nB currently occupied by the page buffer of the node B exceeds the limit threshold n2; if nB > n2, asynchronous reclamation can be performed for the page cache of node A in a memory reclamation manner preconfigured for node B.

In one embodiment, the memory reclamation scheme is a synchronous reclamation scheme. In this case, according to the memory reclamation manner, performing memory reclamation with respect to the page cache of the target system resource management and control component may specifically include: scanning a page cache of the target system resource management and control component, and synchronously recovering unmapped file pages of the target system resource management and control component; if the memory capacity occupied by the page cache of the target system resource management and control component still exceeds the limit threshold, rescanning the page cache of the target system resource management and control component, and synchronously recycling unmapped file pages of the target system resource management and control component until the memory capacity occupied by the page cache of the target system resource management and control component does not exceed the limit threshold; and if the scanning times of the page caches of the target system resource management and control components exceed a first threshold, synchronously recycling the mapping file pages of the target system resource management and control components.

For example, referring to fig. 2, fig. 2 is a flow chart illustrating another page cache restriction method according to an exemplary embodiment. As shown in fig. 2, the traversed target cgroup is node a, and whether the memory capacity nA currently occupied by the page cache of the node a exceeds a limit threshold n1 is detected; if nA is larger than n1 and the node A does not start the asynchronous recovery function, the page cache of the node A can be scanned, and synchronous recovery is carried out on unmapped file pages of the node A; if nA is still more than n1, rescanning the page cache of the node A, and synchronously recovering unmapped file pages of the node A until nA is less than or equal to n1; wherein, if the number of scans of the page cache for node a exceeds 4, the map-file page for node a is allowed to be synchronously reclaimed.

It should be noted that, in the embodiment shown above, the first threshold value is 4, which is merely an exemplary description, and is not meant to limit the present specification in any way.

Because the synchronous reclaiming mode blocks the original thread, and the reclaiming process for the mapped file pages is complex and takes a long time, in the related art, in order to finish synchronous reclaiming for the page caches as soon as possible, the 'direct page reclaiming' is usually carried out by default, that is, only unmapped file pages are generally reclaimed by default. As can be seen from this, the result of the synchronous recovery method in the related art is not ideal in the scenario where the map file page consumption is high. In the embodiment shown in the present specification, if the number of scanning times of the page cache for the target system resource management component exceeds the first threshold, synchronous reclamation for the mapped file page may be allowed, so that in a scenario where the mapped file page consumes more, the effect of the synchronous reclamation mode is improved.

In another embodiment, the memory reclamation scheme is an asynchronous reclamation scheme. In this case, according to the memory reclamation manner, performing memory reclamation with respect to the page cache of the target system resource management and control component may specifically include: scanning a page cache of the target system resource management and control component, and asynchronously recovering clean pages of the target system resource management and control component; the clean page is a memory page in which cached data is written back to a storage medium; the clean page comprises an unmapped file page and a mapped file page; if the memory capacity occupied by the page cache of the target system resource management and control component still exceeds the limit threshold, rescanning the page cache of the target system resource management and control component, and asynchronously recycling the clean page of the target system resource management and control component until the memory capacity occupied by the page cache of the target system resource management and control component does not exceed the limit threshold; if the scanning times of the page cache of the target system resource management and control component exceeds a second threshold value, asynchronous recovery of dirty pages of the target system resource management and control component is allowed; the dirty page is a memory page in which cached data is not written back to the storage medium.

For example, as shown in fig. 2, the traversed target cgroup is a node B, and it is detected whether the memory capacity nB currently occupied by the page buffer of the node B exceeds a limit threshold n2; if nB is greater than n2, and the node B starts an asynchronous recovery function, the page cache of the node B can be scanned, and asynchronous recovery is carried out on clean pages of the node B; if nB is still greater than n2, rescanning the page cache of the node B, and asynchronously recycling the clean page of the node B until nB is less than or equal to n2; wherein asynchronous reclamation of dirty pages for node B is allowed if the number of scans of the page cache for node B exceeds 2.

It should be noted that, in the embodiment shown above, the second threshold value is 2, which is merely an exemplary description, and is not meant to limit the present specification in any way.

Because the memory reclamation for dirty pages is more complex, in the embodiment shown above, asynchronous reclamation may be performed preferentially for clean pages, and if the available memory capacity is still insufficient after rescanning for a certain number of times, asynchronous reclamation for dirty pages may be allowed to improve the effect of the asynchronous reclamation approach.

In another embodiment shown, asynchronous reclamation may be performed in a work queue (work queue) manner; in addition, in order to avoid the situation that the memory recycling process occupies too many CPU resources, in each recycling path, the memory recycling process can actively yield the CPU resources originally used for asynchronous recycling, so as to ensure the normal operation of other processes.

In this case, according to the memory reclamation manner, performing memory reclamation with respect to the page cache of the target system resource management and control component may specifically include: scanning a page cache of the target system resource management and control component, determining memory pages needing to be asynchronously recovered, and asynchronously recovering the memory pages needing to be asynchronously recovered; in response to detecting that available CPU resources of an operating system are insufficient, CPU resources which are originally used for asynchronous recovery of memory pages to be asynchronously recovered by a memory recovery process are scheduled to other processes except the memory recovery process.

For example, if the traversed target cgroup is node a, if the memory capacity nA occupied by the page cache of node a exceeds the limit threshold n1, the page cache of node a may be scanned, to determine the memory page to be asynchronously recovered, and to asynchronously recover the memory page to be asynchronously recovered; in the above process, in response to detecting that available CPU resources of the Linux system are insufficient, the CPU resources that are originally used for asynchronous reclamation of the memory pages that need to be asynchronously reclaimed by the memory reclamation process may be scheduled to other processes other than the memory reclamation process.

It should be noted that, in the embodiment shown above, the operating system may directly schedule the CPU resources originally used for the memory reclamation process to other processes, or may just release the CPU resources originally used for the memory reclamation process to perform asynchronous reclamation, so that other processes have a chance to call the part of CPU resources, which is not described herein.

In another embodiment shown, in traversing for each target system resource management component that needs to be page cache limited, traversing may be prioritized for a parent system resource management component of the target system resource management component. The method may further comprise:

step 108: if the memory capacity occupied by the page cache of the target system resource management and control component does not exceed the limit threshold, detecting whether the memory capacity occupied by the page cache of the parent system resource management and control component of the target system resource management and control component exceeds the limit threshold.

Step 110: and if the memory capacity occupied by the page cache of the parent system resource management and control component exceeds the limit threshold, performing memory reclamation on the page cache of the parent system resource management and control component according to a memory reclamation mode pre-configured for the parent system resource management and control component.

For example, as shown in fig. 2, if the page buffer limiting function is opened for all of the node a, the node B, and the node C, where the node C is a parent group of the node a, may sequentially traverse the above nodes and determine the traversed node as the target cgroup; if the target cgroup is the node A, detecting that the memory capacity nA currently occupied by the page cache of the node A does not exceed the limit threshold n1, and further detecting whether the memory capacity nC currently occupied by the page cache of the parent group node C of the node A exceeds the limit threshold n3 preconfigured for the node C; if nC > n3, memory reclamation can be performed for the page cache of node C according to a memory reclamation mode preconfigured for node C.

The specific implementation manner of performing memory reclamation for the parent group cgroup of the target cgroup is similar to the specific implementation manner of performing memory reclamation for the traversed target cgroup, and is not described herein again.

Continuing with the example shown above, if nC.ltoreq.n3, then traversing the parent group cgroup of node C may continue; alternatively, if nC.ltoreq.n3, the present round of iteration may end, continuing to traverse the next target cgroup (i.e., node B).

It should be noted that, in the embodiment shown above, the parent group cgroup of the target cgroup should also turn on the page cache restriction function.

In another embodiment shown, if the memory capacity occupied by the page cache of the target cgroup (i.e., node a) does not exceed the limit threshold, the iteration of this round may be ended directly, and the next target cgroup (i.e., node B) may be traversed continuously.

According to the technical scheme, the page cache limiting function is started for the target system resource management and control component, the limiting threshold value for the page cache and the memory recycling mode are preconfigured for the target system resource management and control component, and when the memory capacity occupied by the page cache of the target system resource management and control component is detected to exceed the preconfigured limiting threshold value, the memory recycling can be carried out for the page cache of the target system resource management and control component according to the preconfigured memory recycling mode. Therefore, page cache restriction can be performed based on the granularity of the system resource management and control component or the granularity of the operating system, the utilization efficiency of the memory of the container is improved, the occurrence of OOM (on-hook memory) condition can be reduced, and the user experience is improved.

Corresponding to the embodiments of the page buffer limiting method described above, the present specification also provides an embodiment of a page buffer limiting system, and an embodiment of a page buffer limiting device.

In this specification, the page buffer limitation may perform the steps 102 to 106 to implement the technical solution of this specification.

Referring to fig. 3, fig. 3 is a hardware configuration diagram of an electronic device in which a page buffer limiting device is located in an exemplary embodiment. At the hardware level, the device includes a processor 302, an internal bus 304, a network interface 306, memory 308, and non-volatile storage 310, although other hardware requirements are possible. One or more embodiments of the present description may be implemented in a software-based manner, such as by the processor 302 reading a corresponding computer program from the non-volatile storage 310 into the memory 308 and then running. Of course, in addition to software implementation, one or more embodiments of the present disclosure do not exclude other implementation manners, such as a logic device or a combination of software and hardware, etc., that is, the execution subject of the following processing flow is not limited to each logic unit, but may also be hardware or a logic device.

Referring to fig. 4, fig. 4 is a block diagram illustrating a page buffer limiting apparatus according to an exemplary embodiment. The page buffer limiting device can be applied to the electronic equipment shown in fig. 3 to realize the technical scheme of the specification. Wherein the page buffer limiting means may include:

A determining unit 402, configured to determine a target system resource management component that is preconfigured to limit page cache, and determine a limit threshold value and a memory reclamation mode for page cache that are preconfigured for the target system resource management component;

a first detecting unit 404, configured to detect whether a memory capacity occupied by a page cache of the target system resource management and control component exceeds the limit threshold;

and a first reclamation unit 406, configured to perform memory reclamation for the page cache of the target system resource management component according to the memory reclamation manner if the memory capacity occupied by the page cache of the target system resource management component exceeds the limit threshold.

In this embodiment, the memory resource management structure created for the target system resource management component includes a limit function switch variable, a limit threshold variable, and a memory reclamation mode variable;

the determining unit 402 is specifically configured to:

The determining unit 402 is specifically further configured to:

the determining unit 402 is specifically further configured to:

In this embodiment, the memory recovery mode is a synchronous recovery mode; the first recovery unit 406 is specifically configured to:

In this embodiment, the memory reclamation mode is an asynchronous reclamation mode; the first recovery unit 406 is specifically configured to:

In this embodiment, the apparatus further includes:

the second detection unit is used for detecting whether the memory capacity occupied by the page cache of the parent system resource management and control component of the target system resource management and control component exceeds the limit threshold value or not if the memory capacity occupied by the page cache of the target system resource management and control component does not exceed the limit threshold value;

and the second recovery unit is used for carrying out memory recovery on the page cache of the parent system resource management and control component according to a memory recovery mode which is preconfigured for the parent system resource management and control component if the memory capacity occupied by the page cache of the parent system resource management and control component exceeds the limit threshold.

In this embodiment, the determining unit 402 is specifically configured to:

in response to detecting that the available memory resources of the operating system are insufficient, determining a pre-configured target system resource management component requiring limiting page buffering from at least one system resource management component for performing memory resource management on the operating system.

The implementation process of the functions and roles of each unit in the above device is specifically shown in the implementation process of the corresponding steps in the above method, and will not be described herein again.

For the device embodiments, reference is made to the description of the method embodiments for the relevant points, since they essentially correspond to the method embodiments. The apparatus embodiments described above are illustrative only, in that the elements illustrated as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purposes of the present description. Those of ordinary skill in the art will understand and implement the present invention without undue burden.

The system, apparatus, module or unit set forth in the above embodiments may be implemented in particular by a computer chip or entity, or by a product having a certain function. A typical implementation device is a computer, which may be in the form of a personal computer, laptop computer, cellular telephone, camera phone, smart phone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or a combination of any of these devices.

In a typical configuration, a computer includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include volatile memory in a computer-readable medium, random Access Memory (RAM) and/or nonvolatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of computer-readable media.

Computer readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of storage media for a computer include, but are not limited to, phase change memory (PRAM), static Random Access Memory (SRAM), dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), read Only Memory (ROM), electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, read only compact disc read only memory (CD-ROM), digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic disk storage, quantum memory, graphene-based storage or other magnetic storage devices, or any other non-transmission medium, which can be used to store information that can be accessed by the computing device. Computer-readable media, as defined herein, does not include transitory computer-readable media (transmission media), such as modulated data signals and carrier waves.

User information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, presented data, etc.) referred to herein are both user-authorized or fully authorized information and data by parties, and the collection, use and processing of relevant data requires compliance with relevant laws and regulations and standards of the relevant country and region, and is provided with corresponding operation portals for user selection of authorization or denial.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article or apparatus that comprises the element.

The foregoing describes specific embodiments of the present disclosure. Other embodiments are within the scope of the following claims. In some cases, the actions or steps recited in the claims can be performed in a different order than in the embodiments and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

The terminology used in the one or more embodiments of the specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the one or more embodiments of the specification. As used in this specification, one or more embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used in one or more embodiments of the present description to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of one or more embodiments of the present description. The word "if" as used herein may be interpreted as "at … …" or "at … …" or "responsive to a determination", depending on the context.

The foregoing description of the preferred embodiment(s) is (are) merely intended to illustrate the embodiment(s) of the present invention, and it is not intended to limit the embodiment(s) of the present invention to the particular embodiment(s) described.

Claims

1. A method of page cache restriction, the method comprising:

2. The method of claim 1, wherein the memory resource management structure created for the target system resource management component includes a limit function switch variable, a limit threshold variable, and a memory reclamation manner variable;

3. The method of claim 1, wherein the memory reclamation mode is a synchronous reclamation mode; according to the memory recycling mode, performing memory recycling on the page cache of the target system resource management and control component, including:

4. The method of claim 1, wherein the memory reclamation mode is an asynchronous reclamation mode; according to the memory recycling mode, performing memory recycling on the page cache of the target system resource management and control component, including:

5. The method of claim 1, wherein the memory reclamation mode is an asynchronous reclamation mode; according to the memory recycling mode, performing memory recycling on the page cache of the target system resource management and control component, including:

6. The method of claim 1, the method further comprising:

7. The method of claim 1, the determining a preconfigured target system resource management component that requires limiting page buffering, comprising:

8. A page buffer limiting system for implementing the method of any of claims 1 to 7.

9. An electronic device comprises a communication interface, a processor, a memory and a bus, wherein the communication interface, the processor and the memory are connected with each other through the bus;

the memory stores machine readable instructions, the processor executing the method of any of claims 1 to 7 by invoking the machine readable instructions.

10. A machine-readable storage medium storing machine-readable instructions which, when invoked and executed by a processor, implement the method of any one of claims 1 to 7.