Abstract: Methods, computer programs, and systems for managing thread performance in a computing environment based on cache occupancy are provided. In one embodiment, a computer implemented method assigns a thread performance counter to threads being created to measure the number of cache misses for the threads. The thread performance counter is deduced in one embodiment based on performance counters associated with each core in a processor. The method further calculates a self-thread value as the change in the thread performance counter of a given thread during a predetermined period, and an other-thread value as the sum of all the changes in the thread performance counters for all threads except for the given thread. Further, the method estimates a cache occupancy for the given thread based on a previous occupancy for the given thread, and the calculated shelf-thread and other-thread values. The estimated cache occupancy is used to assign computing environment resources to the given thread.

Abstract: In a virtualized system using memory page sharing, a method is provided for maintaining sharing when Guest code attempts to write to the shared memory. In one embodiment, virtualization logic uses a pattern matcher to recognize and intercept page zeroing code in the Guest OS. When the page zeroing code is about to run against a page that is already zeroed, i.e., contains all zeros, and is being shared, the memory writes in the page zeroing code have no effect. The virtualization logic skips over the writes, providing an appearance that the Guest OS page zeroing code has run to completion but without performing any of the writes that would have caused a loss of page sharing. The pattern matcher can be part of a binary translator that inspects code before it executes.

Abstract: A file management system includes a host computer having one or more virtual machines, a switching layer computer configured to manage a namespace map for the virtual machines in the host computer, and a central storage unit. The host computer is connected indirectly to the central storage unit through an in-band IO path that includes the switching layer computer and directly to the central storage unit through an out-of-band IO path. When a virtual machines issues a file operation, a file operation including a data operation is routed to the central storage unit along an out-of-band IO path and a file operation including a metadata operation is routed to the central storage unit along an in-band IO path that includes the switching layer computer.

Abstract: A method for implementing virtual disk reservations on a storage media for multiple distributed applications. The method includes initializing a plurality of virtual disks, wherein each of the virtual disks is instantiated on a physical storage media. A reservation status is determined for each of the virtual disks and a first distributed application that uses at least one virtual disk is executed. Upon an update of the reservation status for the at least one virtual disk by the first distributed application, a notification indicator is set to notify a second distributed application of the update. The update is subsequently recognized and the notification indicator is cleared in order to continue I/O for the first distributed application and the second distributed application.

Abstract: A service level management (SLM) system where the system learns the structure of a web application, monitors the operation of the application, and controls the processing of incoming requests to achieve optimal performance as defined in a service level agreement (SLA). The system is operative for example in enterprise web applications and in enterprise data centers that deploy web applications and optimally is capable of controlling and maintaining a level of service of web applications.

Abstract: A method, apparatus, and system of virtual machine migration using local storage are disclosed. In one embodiment, a method includes creating a current snapshot of an operating virtual machine on a source physical server, storing a write data on a low-capacity storage device accessible to the source physical server and a destination physical server during a write operation on the destination physical server, and launching the operating virtual machine on the destination physical server when a memory data is copied from the source physical server to the destination physical server. The current snapshot may be a read-only state of the operating virtual machine frozen at a point in time. A time and I/O that may be needed to create the current snapshot that may not increase with a size of the operating virtual machine.

Abstract: Writes to blocks of a protected storage volume that occur between the beginning of a prior backup interval and the beginning of a current backup interval are tracked using a first snapshot that is maintained through the current backup interval. At the beginning of the current backup interval, a second snapshot is generated. Blocks that are indicated by a dirty block list of the first snapshot as having been changed are read from the snapshot volume for the second snapshot and copied to a backup storage volume. For the next backup interval, the second snapshot or alternatively, a newly generated third snapshot, is used to track writes to blocks of a protected storage volume that occur between the beginning of the current backup interval and the beginning of a next backup interval.

Abstract: Writes to a storage device of a protected computer system are tracked in a manner that accounts for those writes that may occur during a system reboot process when the file system is not available. During the shutdown process, write tracking data is maintained in system memory and is written into storage locations allocated to the tracking file after the file system has been dismounted so that any writes that may occur during the file system dismount can be captured. During the boot process, temporary write tracking data is maintained in system memory even before the file system is mounted so that any writes that may occur immediately after the file system mount can be captured. The temporary write tracking data is later merged with the tracking data contained in the tracking file and the merged tracking data is used to track further writes to the storage device.

Abstract: A data center comprising plural computer hosts and a storage system external to said hosts is disclosed. The storage system includes storage blocks for storing tangibly encoded data blocks. Each of said hosts includes a deduplicating file system for identifying and merging identical data blocks stored in respective storage blocks into one of said storage blocks so that a first file exclusively accessed by a first host of said hosts and a second file accessed exclusively by a second host of said hosts concurrently refer to the same one of said storage blocks.

Abstract: Available buffers in the memory space of a guest operating system of a virtual machine are provided to a network interface controller (NIC) for use during direct memory access (DMA) and the guest operating system is notified accordingly when data is written into such available buffers. These capabilities obviate the requirement of using hypervisor memory as a staging area to determine which virtual machine to forward incoming data.

Abstract: At least one target configuration of a host at a virtualization software level is automatically assembled based on a source configuration. A policy based profile describing the source configuration is processed. A configuration specification describing the target configuration is automatically created, based on the policy based profile describing the source configuration. The configuration specification is automatically applied to target configurations, such that the target configuration(s) are compliant with the policy based profile.

Abstract: A method for managing storage for a desktop pool is described. The desktop pool includes a plurality of virtual machines (VMs), each VM having at least one virtual disk represented as a virtual disk image file on one of a plurality of datastores associated with the desktop pool. To identify a target datastore for a VM, a weight of each datastore is calculated. The weight may be a function of a virtual capacity of the datastore and the sum of maximum sizes of all the virtual disk image files on the datastore. The virtual capacity is a product of the data storage capacity of the datastore and an overcommit factor assigned to the datastore. The target datastore is selected as the datastore having the highest weight. The VM may is moved to or created on the target datastore.

Abstract: A virtual machine (VM) is accessed by receiving user log-in information, the log-in information identifying a user and a corresponding VM, the VM having a local copy and a remote copy. A selected copy of the VM is identified based on at least one of a policy and a user selection, the selected copy being one of the local copy and the remote copy of the VM. A desktop generated by the selected copy of the VM is presented to the user in a common application graphical user interface, the common application graphical user interface being used regardless as to whether the selected copy of the VM is the local copy or the remote copy.

Abstract: A method of reducing power consumption of a server cluster of host systems with virtual machines executing on the host systems is disclosed. The method includes recommending host system power-on when there is a host system whose utilization is above a target utilization, and recommending host system power-off when there is a host system whose utilization is below the target utilization. Recommending host system power-on includes calculating impact of powering on a standby host system with respect to reducing the number of highly-utilized host systems in the server cluster. The impact of powering on is calculated by simulating moving some virtual machines from highly utilized host systems to the standby host system being recommended to be powered on. Recommending host system power-off includes calculating impact of powering off a host system with respect to decreasing the number of less-utilized host systems in the server cluster.

Abstract: Prior to or while the state of a virtual machine (“VM”) is being saved, such as in connection with the suspension or checkpointing of a VM, a set of one or more “active” memory pages is identified, this set of active memory pages comprising memory pages that are in use within the VM before operation of the VM is suspended. This set of active memory pages may constitute a “working set” of memory pages. To restore the state of the VM and resume operation, in some embodiments, (a) access to persistent storage is restored to the VM, device state for the VM is restored, and one or more of the set of active memory pages are loaded into physical memory; (b) operation of the VM is resumed; and (c) additional memory pages from the saved state of the VM are loaded into memory after operation of the VM has resumed.

Abstract: A source virtual machine (VM) hosted on a source server is migrated to a destination VM on a destination server without first powering down the source VM. After optional pre-copying of the source VM's memory to the destination VM, the source VM is suspended and its non-memory state is transferred to the destination VM; the destination VM is then resumed from the transferred state. The source VM memory is either paged in to the destination VM on demand, or is transferred asynchronously by pre-copying and write-protecting the source VM memory, and then later transferring only the modified pages after the destination VM is resumed. The source and destination servers preferably share common storage, in which the source VM's virtual disk is stored; this avoids the need to transfer the virtual disk contents.

Abstract: Instead of transferring a large original file, such as a virtual-machine image file, from a source system to a target system, the original file is encoded to define a recipe file that is transferred. The recipe is then decoded to yield a duplicate of the original file on the target system. Encoding involves identifying standard blocks in the original file and including standard-block identifiers for the standard blocks in the recipe in lieu of the original blocks. Decoding involves an exchange with a standard-block identifier server system, which provides standard blocks in response to received standard-block identifiers.

Abstract: For a virtual memory of a virtualized computer system in which a virtual page is mapped to a guest physical page which is backed by a machine page and in which a shadow page table entry directly maps the virtual page to the machine page, reverse mappings of guest physical pages are optimized by removing the reverse mappings of certain immutable guest physical pages. An immutable guest physical memory page is identified, and existing reverse mappings corresponding to the immutable guest physical page are removed. New reverse mappings corresponding to the identified immutable guest physical page are no longer added.

Abstract: One embodiment is a method for providing incremental backups for a source computing machine, the method including: (a) creating a first backup snapshot including a virtual machine (VM) snapshot of an initial copy of a source computing machine volume, wherein said VM snapshot includes a timestamp and a first redo log file; (b) reconfiguring and customizing said first backup snapshot to create a first bootable VM, writing changes associated with said reconfiguring and customizing into said first redo log file, then creating a first bootable snapshot including a VM snapshot of said first bootable VM, wherein said VM snapshot of said first bootable VM includes a timestamp for said first bootable VM and a redo log file; (c) performing an incremental update of said first backup snapshot or a subsequent backup snapshot, then creating a subsequent backup snapshot including a VM snapshot of said incremental update, wherein said VM snapshot of said incremental update includes a timestamp for said incremental update and

Abstract: Methods, systems and computer readable media for granting class level trust in an open application programming interface (API) system is disclosed. The method includes defining a common information model (CIM) architecture, and the CIM architecture is configured with a CIM managed object (CIMOM) for managing client requests made through APIs. The APIs are handled by the CIMOM and the CIMOM accesses schemas that include one or more classes. The method includes applying trust level settings to particular ones of the one or more classes of the schemas, and the trust level settings define client permissions to the particular classes. The method further includes hiding the particular classes to clients that lack a trust level sufficient to access the particular classes. Clients that lack the trust level are serviced with classes that do not have the applied trust level settings.