Abstract: A latest status record of an object in a local storage node is obtained as a local status record of the object. The status record includes a name of an operation changing the object, a timestamp of the operation changing the object, a first status flag, and a second status flag. The first status flag indicates whether a synchronization of the object from current object storage node to another object storage node is executed. The second status flag indicates whether a synchronization of the object from another object storage node to the current object storage node is executed. The latest status record of the object is obtained of the object in from a remote object storage node as a remote status record of the object. A synchronization of the object is executed based on the local status record and the remote status record.

Abstract: A distributed computing system provides at least one service, and the service is provided by resources of the distributed computing system. Resources are represented by a topology graph including storage, application and database server nodes joined by edges indicative of relationships between nodes. Predefined parameters are monitored that are indicative of operating characteristics of the distributed computing system when providing the service. Values of the predefined parameters are compared with respective predetermined performance threshold values. The performance threshold values are determined based on a service level agreement (SLA). The SLA includes a service level objective (SLO). The performance threshold values are indicative of the respective operating characteristics prior to an event. Rules are provided for selecting a combination of application, storage and database server nodes to meet the SLO for each parameter of the parameter.

Abstract: A latest status record of an object in a local storage node is obtained as a local status record of the object. The status record includes a name of an operation changing the object, a timestamp of the operation changing the object, a first status flag, and a second status flag. The first status flag indicates whether a synchronization of the object from current object storage node to another object storage node is executed. The second status flag indicates whether a synchronization of the object from another object storage node to the current object storage node is executed. The latest status record of the object is obtained of the object in from a remote object storage node as a remote status record of the object. A synchronization of the object is executed based on the local status record and the remote status record.

Abstract: A latest status record of an object in a local storage node is obtained as a local status record of the object. The status record includes a name of an operation changing the object, a timestamp of the operation changing the object, a first status flag, and a second status flag. The first status flag indicates whether a synchronization of the object from current object storage node to another object storage node is executed. The second status flag indicates whether a synchronization of the object from another object storage node to the current object storage node is executed. The latest status record of the object is obtained of the object in from a remote object storage node as a remote status record of the object. A synchronization of the object is executed based on the local status record and the remote status record.

Abstract: A method and system for storage of an aggregation file and method and system for compression of the same. The method for compressing an aggregation file includes: acquiring the aggregation file to be compressed; copying remaining files in the acquired aggregation file into a new aggregation file based on metadata of a deleted object stored in a deletion file corresponding to the acquired aggregation file; and removing the acquired aggregation file. The present invention also provides a system for compressing an aggregation file and a method and system for storing an aggregation file.

Abstract: According to various embodiments, a method and apparatus for providing a virtual appliance are described. The method includes: obtaining metadata of a specific virtual appliance based on a received request for obtaining the specific virtual appliance, the metadata describing information about virtual machines involved in the specific virtual appliance, determining an association relationship between the specific virtual appliance and at least one other virtual appliance according to the metadata, and providing resource information for obtaining the specific virtual appliance according to the association relationship, the resource information including a plurality of resource addresses, at least one of the plurality of resource addresses pointing to a storage location of the at least one other virtual appliance.

Abstract: A distributed computing system provides at least one service, and the service is provided by resources of the distributed computing system. Resources are represented by a topology graph including storage, application and database server nodes joined by edges indicative of relationships between nodes. Predefined parameters are monitored that are indicative of operating characteristics of the distributed computing system when providing the service. Values of the predefined parameters are compared with respective predetermined performance threshold values. The performance threshold values are determined based on a service level agreement (SLA). The SLA includes a service level objective (SLO). The performance threshold values are indicative of the respective operating characteristics prior to an event. Rules are provided for selecting a combination of application, storage and database server nodes to meet the SLO for each parameter of the parameter.

Abstract: A distributed computing system provides at least one service, and the service is provided by resources of the distributed computing system. Resources are represented by a topology graph including storage, application and database server nodes joined by edges indicative of relationships between nodes. Predefined parameters are monitored that are indicative of operating characteristics of the distributed computing system when providing the service. Values of the predefined parameters are compared with respective predetermined performance threshold values. The performance threshold values are determined based on a service level agreement (SLA). The SLA includes a service level objective (SLO). The performance threshold values are indicative of the respective operating characteristics prior to an event. Rules are provided for selecting a combination of application, storage and database server nodes to meet the SLO for each parameter of the parameter.

Abstract: A method and system for storage of an aggregation file and method and system for compression of the same. The method for compressing an aggregation file includes: acquiring the aggregation file to be compressed; copying remaining files in the acquired aggregation file into a new aggregation file based on metadata of a deleted object stored in a deletion file corresponding to the acquired aggregation file; and removing the acquired aggregation file. The present invention also provides a system for compressing an aggregation file and a method and system for storing an aggregation file.

Abstract: A latest status record of an object in a local storage node is obtained as a local status record of the object. The status record includes a name of an operation changing the object, a timestamp of the operation changing the object, a first status flag, and a second status flag. The first status flag indicates whether a synchronization of the object from current object storage node to another object storage node is executed. The second status flag indicates whether a synchronization of the object from another object storage node to the current object storage node is executed. The latest status record of the object is obtained of the object in from a remote object storage node as a remote status record of the object. A synchronization of the object is executed based on the local status record and the remote status record.

Abstract: A computer program product and method for estimating a filter factor for access path optimization in a database are provided. The method includes extracting from a statement segment for database query a relation condition which defines the relationship between a variable and a first table. The method includes obtaining first statistics information according to the relation condition and the statistics information of the first table. The method includes extracting from the statement segment a filter condition which defines the relationship between the variable and a second table. The method includes obtaining second statistics information according to the filter condition and the statistics information of the second table, and according to the first statistics information and the second statistics information, estimating the filter factor of the filter condition.

Abstract: According to various embodiments, a method and apparatus for providing a virtual appliance are described. The method includes: obtaining metadata of a specific virtual appliance based on a received request for obtaining the specific virtual appliance, the metadata describing information about virtual machines involved in the specific virtual appliance, determining an association relationship between the specific virtual appliance and at least one other virtual appliance according to the metadata, and providing resource information for obtaining the specific virtual appliance according to the association relationship, the resource information including a plurality of resource addresses, at least one of the plurality of resource addresses pointing to a storage location of the at least one other virtual appliance.

Abstract: A distributed computing system provides at least one service, and the service is provided by resources of the distributed computing system. Resources are represented by a topology graph including storage, application and database server nodes joined by edges indicative of relationships between nodes. Predefined parameters are monitored that are indicative of operating characteristics of the distributed computing system when providing the service. Values of the predefined parameters are compared with respective predetermined performance threshold values. The performance threshold values are determined based on a service level agreement (SLA). The SLA includes a service level objective (SLO). The performance threshold values are indicative of the respective operating characteristics prior to an event. Rules are provided for selecting a combination of application, storage and database server nodes to meet the SLO for each parameter of the parameter.

Abstract: A test coverage analysis method and corresponding apparatus are disclosed, wherein, by executing the program under test using one or more test cases, generating one or more heapdump files containing the call stack information of the program under test, and analyzing the call stack information in the one or more heapdump files, the coverage information of the one or more test cases in terms of functions in the program under test is obtained.

Abstract: A test coverage analysis method and corresponding apparatus are disclosed, wherein, by executing the program under test using one or more test cases, generating one or more heapdump files containing the call stack information of the program under test, and analyzing the call stack information in the one or more heapdump files, the coverage information of the one or more test cases in terms of functions in the program under test is obtained.