40 results about "Dirty page" patented technology

The invention discloses a three-level cache replacement method based on dirty page perception and adaptive capacity, and belongs to the technical field of computer memory cache management. The method comprises the following steps of: constructing a short-time-efficiency queue, a medium-time-efficiency queue and a global queue in a CXL extended memory equipment side cache; executing object insertion, migration and metadata updating according to the hit condition of the access request in each queue; when the cache space is insufficient, the access count, the dirty page mark and the dirty page revival mark are combined to execute eviction judgment; and calculating a return visit ratio based on global queue identifier insertion times and return visit times, and dynamically adjusting short-time-efficiency and medium-time-efficiency queue capacities. According to the method, the problems of high dirty page write-back cost and inflexible cache space distribution in the CXL extended memory are solved, and the redundant write-back overhead is reduced, the utilization efficiency of the cache space is improved and the access delay is reduced through collaborative optimization of the access characteristics, the dirty page state and the elimination return visit behavior.

The invention discloses an online migration method, device and equipment of a virtual machine, and relates to the technical field of virtualization, the method comprises the following steps: in an online migration process of a source virtual machine, according to memory static page information of the source virtual machine and a target virtual machine, transmitting full memory data of the source virtual machine to the target virtual machine; according to the dirty marking frequency of each dirty memory page in the source virtual machine, obtaining a page type corresponding to each dirty memory page; according to the page type corresponding to each dirty memory page, determining a to-be-transmitted dirty page of the iteration transmission; if the current iteration transmission is not the last iteration transmission, transmitting the dirty page to be transmitted of the current iteration transmission to the target virtual machine; if the current iteration transmission is the last iteration transmission, pausing the source virtual machine, and transmitting the dirty page to be transmitted of the current iteration transmission to the target virtual machine; according to the method, the data volume needing to be transmitted in the online migration process of the virtual machine can be reduced, the migration speed is increased, and the influence on the system performance is reduced.

A computing system may access a source device configured to store device traffic in a source device queue. The computing system may launch, by one or more worker nodes of a control plane of the computing device, a destination device. The computing system may transmit a source device state to the destination device. The control plane worker nodes may configure the destination device from the source device state. The computing system may instruct the source device to pause storing the device traffic to the source device guest memory. The computing system may store dirty page information in the computing system memory. The computing system may transmit the dirty page information to the destination guest memory. The computing system may instruct the destination device to resume storing the device traffic to the destination guest memory.

The invention relates to a database fault recovery method and device, a storage medium and electronic equipment. The method comprises the steps that when a database normally runs, a WAL log is written into a disk, and meanwhile, a log record is pre-analyzed through a background asynchronous thread to extract core semantic information of the log record; constructing a cache structure sorted according to table space identifiers and data page numbers in the shared memory, and storing the core semantic information in the cache structure in a recovery-oriented compact format; when the check point is executed, the memory dirty page is flashed to a disk, and the cache initial position corresponding to the check point in the cache structure serves as metadata to be written into a control file; and after the database crashes and is restarted, acquiring a cache initial position from the control file, loading all core semantic information entries behind the cache initial position in the cache structure according to the cache initial position, positioning a target data page, and modifying the target data page. The technical problem that an existing database collapse recovery technology is low in recovery speed is solved.

The application discloses a file unshelling method and electronic equipment, and relates to the technical field of computer security, and comprises the following steps: inserting a probe at a target system call of a kernel, and injecting the probe into a target program; identifying a suspiciously shelled process through the target program; monitoring a memory permission change behavior performed by the suspiciously shelled process through the target program, and counting a permission change frequency of a memory region, an entropy value of the memory region and a call chain depth; when it is confirmed that the suspiciously shelled process is in an unshelling stage according to the permission change frequency, the entropy value and the call chain depth, writing data decrypted by the suspiciously shelled process into a target buffer through the target program; reading the data from the target buffer in a user mode, and recombining the data into a memory image according to a base address and a dirty page bitmap and writing the memory image back to a file. The method can avoid I / O bottlenecks caused by full memory dumping, reduce invalid data in the user mode, and reduce CPU occupation and memory bandwidth.

This invention relates to the field of data flow control technology, and more particularly to a method, apparatus, device, and medium for flow control of a data buffer. Based on the number of first dirty pages at the previous time step, the number of second dirty pages at the current time step, the rate of change of the number of dirty pages at the previous time step, and the rate of change of the number of dirty pages at the current time step, the target flow control delay for the current time step is calculated. The flow of the data buffer is controlled according to the target flow control delay. Based on the amount of dirty page data and the rate of change of the number of dirty pages at adjacent time steps, a target flow control strategy for the database buffer is determined. Based on the target flow control strategy, the target flow control delay for the current time step is calculated. The flow of the data buffer is controlled according to the target flow control delay. By periodically calculating the buffer flow control delay, the data buffer automatically and dynamically adjusts the buffer allocation delay according to business pressure, thereby avoiding performance fluctuations caused by buffer exhaustion due to excessive business pressure.

A physical host includes a memory, a first buffer, a second buffer, a third buffer and a processor. The first buffer stores a log regarding dirty pages. The second buffer stores a dirty bitmap, where the dirty bitmap is written into the second buffer according to the log read from the first buffer. The third buffer stores the dirty bitmap. The processor obtains the current memory address to be migrated and a destination memory address, and marks a page table corresponding to the memory address to be migrated as dirty pages and writes the log marked as the dirty pages into the first buffer when the memory address to be migrated is written. The processor includes a memory copy engine for reading the dirty bitmap from the third buffer, and copying the content corresponding to the dirty pages to the destination memory according to the dirty bitmap.

The invention provides a dirty page brushing method and a related product. The dirty page disk brushing method is applied to any node in a database cluster, and comprises the following steps: responding to a global check point process started by the database cluster; participating in the collection of redo sites by the database cluster; node-level dirty page disc brushing is carried out for multiple times; synchronizing dirty page disk brushing progress of the buffer area with other nodes; and performing one-time cluster-level dirty page disk brushing with other nodes. The method has the advantage that the dirty page brushing efficiency during the global check point period can be improved.

An input / output memory management unit (IOMMU) comprises address translation circuitry to control address translation in response to input / output memory system transactions issued by one or more input / output devices; at least one dirty page tracking base address register to store a base address of a dirty page buffer structure for tracking addresses of dirty pages of address space; and dirty page tracking circuitry to: detect whether an input / output memory system transaction associated with a given translation context for which dirty page tracking is enabled causes a transition of a given page of address space from clean to dirty, and in response to detecting the input / output memory system transaction associated with the given translation context for which dirty page tracking is enabled causing a transition of the given page from clean to dirty, issue a write memory access request requesting that a location within a selected dirty page buffer structure, identified using the base address indicated in a selected dirty page tracking base address register, is updated to identify a page address of the given page.

The invention discloses a data storage management method based on a FLASH in an MCU (Microprogrammed Control Unit). A storage space is divided into a node information area and a node data area, and empty / non-full / full / dirty four-state identification bits are configured for each page; new data are sequentially written into idle positions, original data are marked as a dirty state during data updating, and updated complete data are written into new positions of the storage area; and when the space is insufficient, triggering erasing balance, migrating valid data of dirty pages to empty pages, and then erasing the dirty pages to release the space. A single-identification-bit updating state and a whole-page erasing mechanism are adopted, the FLASH erasing frequency is remarkably reduced, the service life is prolonged, and meanwhile variable-length data storage and system starting consistency guarantee are supported.

The invention relates to the technical field of virtual machine migration, and discloses a virtual machine real-time migration method based on credential cloud, which comprises the following steps of: normally operating a source host to be migrated, preparing resources of a target host, dividing priorities of applications of the source host, and distinguishing high-priority applications from low-priority applications; copying all memories in the source host to a destination host by using pre-copying; iteratively copying all dirty pages generated by the high-priority applications to a destination host; when a dirty page with a high priority in the virtual machine reaches a shutdown condition, pausing the operation of the source host; after all the remaining dirty pages with high priority in the source virtual machine are completely copied to the target host, the target host is started, and the application with high priority of the target host can run normally; copying dirty pages of the low-priority applications to a destination host; according to the method, the priorities of the applications are graded, a certain strategy is adopted, the overall migration time is shortened, and the downtime of the virtual machine is further shortened.

The invention discloses a method for supporting simultaneous live migration of multiple virtual machines without packet loss by combining software and hardware in the field of virtual machine migration. The method comprises the following steps: creating virtual machine live migration auxiliary equipment D1 and a hardware dirty page reporting queue; creating a dirty page processing thread to record dirty page information; according to the live migration request, the vDPA driver registers to-be-migrated virtual machine information to the auxiliary device D1, and the auxiliary device D1 starts dirty page capturing and reporting; and after migration is finished, the vDPA driver cancels migrated virtual machine information and releases resources. According to the method, dirty page capturing and reporting are achieved through hardware, and performance loss of a pure software scheme is avoided; hardware only needs to configure a report queue, so that the hardware design complexity is reduced; independent management of dirty pages of multiple virtual machines is realized through a mapping table, and simultaneous thermal migration of the multiple virtual machines is supported; meanwhile, an exception handling mechanism is introduced, and reliability is improved. According to the method, the thermal migration performance, the hardware complexity and the resource consumption are considered, and the method is suitable for various vDPA virtual machine migration scenes.

The application discloses a WebAssembly application hot migration runtime model method for a serverless scene, relates to the technical field of cloud computing and edge computing, and designs a WASM runtime mechanism supporting seamless hot migration across architectures, including designing a unified compilation model to realize unified memory space layout of compilation products of different architectures; and proposing a software-implemented, lightweight dirty page tracking memory migration strategy, which can avoid the burden of process-level migration and maintain the lightweight characteristics of WASM.

The invention provides a virtual machine live migration method, electronic equipment, a storage medium and a program product, and the method comprises the steps: in response to a live migration request for a virtual machine, determining a minimum dirty page generation interval corresponding to the transmission speed of live migration; in each round of synchronous operation implemented according to the live migration request, a write memory management strategy is adopted to manage the write memory operation of the round, so that the dirty page generation interval corresponding to the write memory operation of the first part is allowed to be smaller than the minimum dirty page generation interval; the dirty page generation interval corresponding to the memory writing operation of the second part is limited to be not smaller than the minimum dirty page generation interval; and gradually strengthening the limitation of the write memory management strategy on dirty pages so as to gradually reduce the dirty pages generated by each round at the interval smaller than the minimum dirty page generation interval.

Embodiments of the present application provide a solid state disk based accelerated power-on method, a solid state disk, a computer device and a computer readable storage medium, the method comprising: when detecting that the power supply voltage of the solid state disk is abnormal, brushing the current first mapping table to the storage area of the solid state disk; when detecting that the power supply voltage returns to normal, reading the first mapping table in the storage area of the solid state disk, and restoring a temporary mapping table based on the first mapping table; and restoring the second mapping table when the voltage is abnormal according to the dirty page bitmap of the second mapping table before the voltage is abnormal and the temporary mapping table. In the case of detecting that the voltage of the external power supply returns to normal, the second mapping table can be directly restored by reading the first mapping table in the storage area of the SSD, avoiding the problem of long recovery time and long SSD power-on time caused by scanning user data to restore the second mapping table, and shortening the power-on time of the SSD.

The present application belongs to the technical field of computer information security, and particularly relates to a cloud host security baseline checking method and system based on virtual machine introspection, which comprises the following steps: accessing a target virtual machine through a host virtualization management program layer and dividing physical memory pages, obtaining physical memory dirty page states and system I / O load; according to the dirty page states of the physical memory pages in a historical observation window and a physical neighborhood set, obtaining an activity accumulation index and a spatial neighborhood linkage index at the current time, respectively; obtaining a checking trigger score according to the activity accumulation index, the spatial neighborhood linkage index and the system I / O load, and realizing security baseline checking based on the threshold relationship of the checking trigger score. The present application can identify normal business hotspots and abnormal tampering behaviors, and reduce the checking frequency when the system is under high load, thereby realizing low-overhead agentless security baseline checking.

The invention relates to the technical field of cloud computing containers, and provides a container thermal migration method based on memory snapshot difference compression, which comprises the following steps: in a normal operation stage of a container, initiating pre-migration preparation through a CRIU framework, continuously capturing dirty pages marked by a copy-on-write mechanism in a fixed period to form a difference page set, and storing the difference page set in a database; calculating the access popularity of each dirty page; dividing dirty pages of the difference page set into hot pages, warm pages and cold pages according to access popularity, and compressing the hot pages, the warm pages and the cold pages by adopting a self-adaptive compression strategy; constructing a three-level priority sending queue at a source node, and entering a network stack according to a priority sequence of a hot page, a warm page and a cold page; and when a convergence condition is met, suspending the container, only transmitting the last group of hot pages and necessary warm pages, and decompressing and rearranging memory pages at a target node according to a serial number to complete container recovery. According to the method, online container migration with high compression ratio, low CPU overhead, short downtime and high migration success rate is realized.

The embodiment of the invention discloses a data migration method and device, a to-be-migrated virtual machine, a medium and a product, and the method comprises the steps: determining the data block granularity of a disk bitmap of the to-be-migrated virtual machine based on input / output data generated in the operation process of the to-be-migrated virtual machine; after each round of disk dirty page transmission is completed, determining target transmission time of next round of memory dirty page transmission based on a first disk dirty page rate obtained by tracking a disk bitmap determined by the data block granularity; and scheduling the next round of memory dirty page transmission according to the target transmission time.

The present disclosure provides a dirty page migration method, a dirty page migration device, an electronic device, a medium and a product, and belongs to the technical field of virtual machines. The method comprises: obtaining task execution data of a source virtual machine, the task execution data being used to represent information of a target task currently executed by the source virtual machine; performing storage access prediction on the task execution data to obtain storage access prediction data of the source virtual machine; determining storage page transmission priorities according to the storage access prediction data, the storage page transmission priorities being used to represent transmission priorities of each storage page in the source virtual machine; and migrating a plurality of storage pages of the source virtual machine to a target virtual machine based on the storage page transmission priorities. The embodiments of the present disclosure can reduce repeated transmission of dirty data, reduce network overhead, and improve migration efficiency.

This application provides example methods for migrating a virtual machine and example apparatuses. One example physical host includes a source-end virtual machine and a physical function (PF) driver, where the source-end virtual machine is configured to send a first instruction to a source-end pass-through device via the PF driver, where the first instruction instructs the source-end pass-through device to record a storage address of dirty page data in the source-end pass-through device, and the dirty page data is data written by the source-end pass-through device to a memory corresponding to the source-end virtual machine. The source-end virtual machine is configured to obtain the storage address that is of the dirty page data and that is recorded by the source-end pass-through device, and send to-be-migrated data to a destination-end virtual machine.

The invention provides a real-time migration method and system for containerized applications. Under the condition that the source container in the source host runs continuously, copying memory data and file system data of the source container into the target host so as to perform pre-migration; in the pre-migration process, dirty pages in the source host are tracked; the dirty pages are changed memory pages; synchronizing dirty page data generated by the source container in the pre-migration process to a target host through at least one round of iteration process in an incremental synchronization mode so as to realize incremental synchronization; judging whether the incremental synchronization process is finished or not, and if yes, executing network switching; when network switching is executed, capturing a network connection state at a kernel network layer of the source host, synchronizing the network connection state to the target host, and redirecting network traffic to the target host; and activating the target container on the target host, and releasing resources of the source container on the source host. According to the invention, the service interruption time in the containerized application migration process can be reduced.

The invention discloses a virtual machine state synchronization method, device and equipment and a readable storage medium, and is applied to the technical field of virtual machines, and the method comprises the following steps: when it is determined that a virtual machine state synchronization process is started, performing data retrieval on a latest dirty page bitmap by using a main virtual machine, and determining a memory page with data change; using the main virtual machine to take continuous memory dirty pages in the memory pages with the data change as a whole segment of memory incremental data, synchronizing the whole segment of memory incremental data to the standby virtual machine, and stopping retrieval until all memory addresses of the main virtual machine are traversed. Compared with the situation that after a dirty memory page is found at present, the next dirty memory page is continuously retrieved after the data of the memory page is synchronized to the SVM from the PVM, and different processes are mutually blocked, other memory addresses of the virtual machine can be traversed without waiting for a current incremental data sending result, so that the data transmission efficiency is improved. And the continuous memory dirty pages are used as the whole segment of memory incremental data for synchronization, so that the synchronization efficiency of the virtual machine data is improved.

The application discloses a three-level cache replacement method based on dirty page awareness and adaptive capacity, and belongs to the technical field of computer memory cache management. The method comprises the following steps: constructing short-time queues, medium-time queues and global queues on the side of a CXL extended memory device cache; performing object insertion, migration and metadata update according to the hit condition of each queue; when the cache space is insufficient, performing eviction determination in combination with access count, dirty page flag and dirty page revival flag; calculating the revisit ratio based on the global queue identification insertion frequency and revisit frequency, and dynamically adjusting the short-time queue capacity and the medium-time queue capacity. The application solves the problems of high dirty page write-back cost and inflexible cache space allocation in the CXL extended memory, optimizes the access characteristics, dirty page state and elimination revisit behavior in cooperation, reduces the redundant write-back overhead, improves the cache space utilization efficiency and reduces the access time delay.

The invention discloses a file shelling method and electronic equipment, and relates to the technical field of computer security, and the file shelling method comprises the following steps: inserting a probe at a target system calling position of a kernel, and injecting a target program into the probe; identifying a suspicious shell adding process through the target program; monitoring a memory permission change behavior executed by the suspicious packing process through the target program, and counting the permission change frequency of the memory region, the entropy value of the memory region and the call chain depth; when it is confirmed that the suspicious packing process is in the unpacking stage according to the permission change frequency, the entropy value and the call chain depth, data decrypted by the suspicious packing process is written into a target buffer area through a target program; and reading the data from the target buffer area in the user mode, recombining the data into a memory mirror image according to the base address and the dirty page bitmap, and writing the memory mirror image back to the file. According to the method, the I / O bottleneck caused by full-memory dump can be avoided, invalid data in a user mode can be reduced, and CPU occupation and memory bandwidth can be reduced.

The invention discloses a performance optimization method and device for first-time writing after snapshot and a medium, relates to the technical field of data writing, and provides the performance optimization method for first-time writing after snapshot aiming at the problem that after a Reflink technology is introduced into an OCFS2 file system, the performance is greatly reduced during first-time writing after snapshot creation. Direct IO writing is modified into buffer IO writing, and then data is brushed down to a disk through a dirty page brushing-down mechanism to complete data disk dropping. Based on the write modification operation, the write overhead can be reduced by using the high-speed characteristic of the memory, so that the effect of improving the write performance of the file system is achieved. Furthermore, according to the method, delayed downbrushing is adopted during downbrushing of the dirty pages, the time for writing the dirty pages back to the disk can be delayed on the premise that it is guaranteed that the data can finally fall into the disk in time, and therefore the situation that precious user data IO bandwidth is occupied by downbrushing of the dirty pages is avoided, and the effect of improving the writing performance of a file system is achieved.

A first portion of a bitmap from a set of bitmaps designated as a current active bitmap at a first point in time is modified responsive receiving a write request for a target page within a namespace of a memory device during migration of the namespace. The first portion containing a bit associated with the target page. The modified first portion is stored. Whether a second portion of a bitmap from the set of bitmaps designated as the current active bitmap at a second point in time matches the modified first portion is determined. The second portion contains a bit associated with the target page. The current active bitmap has not changed from the first point in time is determined responsive to determining that the second portion matches the modified first portion.

Various embodiments of this disclosure provide file write protection methods, apparatuses, electronic devices, storage media, and products. The file write protection method according to an embodiment includes: when an application modifies a page of a target file in the page cache through a file write operation, intercepting the dirty page marking function of the system call executing the file write operation; determining that the target file is in a protected state if the inode of the target file has a protection flag set; and based on the target file being in a protected state, intercepting the dirty page marking function's dirty page marking of the target file's pages. Through this disclosure, file write protection can intercept file writes in a timely manner at the page cache level, effectively blocking malicious file writes.

The invention discloses an embedded system snapshot optimization method and system oriented to a resource-constrained environment. The method comprises the following steps: firstly, configuring snapshot parameters according to hardware parameters of the embedded equipment; secondly, constructing a page state management structure, and continuously capturing page writing events during scanning in a pre-copying stage so as to distinguish a high-writing-frequency page from a low-writing-frequency page; executing multiple rounds of traversal in the pre-copying stage to ensure the convergence of the working set, and judging whether to terminate the pre-copying stage or not according to the convergence; storing the identified working set pages instead of all dirty pages in the shutdown stage again, setting write protection for non-working set pages, and restoring the operation of the virtual machine; after the operation of the virtual machine is recovered, a non-working set is stored in the background; and finally, real-time redundancy elimination and writing are carried out. According to the method, the shutdown duration can be effectively shortened in an embedded scene with dense dynamic write-in and obvious working set change, the snapshot duration and the storage write-in burden are reduced, and the overall performance of an embedded virtualization operation framework is improved.

The embodiment of the application discloses a data migration method and device, a virtual machine to be migrated, a medium and a product. The method comprises the following steps: determining the data block granularity of the disk bitmap of the virtual machine to be migrated based on the input / output data generated by the virtual machine to be migrated during operation; determining the target transmission time of the next round of memory dirty page transmission based on the first disk dirty page rate obtained by tracking the disk bitmap determined by the data block granularity after the completion of each round of disk dirty page transmission; and scheduling the transmission of the next round of memory dirty pages according to the target transmission time.