Abstract: Technologies for quality of service (QoS) management include a computing device having a physical storage volume and multiple processor cores. A management thread reads I/O counters that are each associated with a logical volume and a processor core. The logical volumes are backed by the physical storage volume. The management thread configures stop bits as a function of the I/O counters and multiple QoS parameters. Each stop bit is associated with a logical volume and a processor core. The QoS parameters include minimum guaranteed bandwidth and optional maximum allowed bandwidth for each logical volume. A worker thread reads the stop bit associated with a logical volume and a processor core, accesses the logical volume if the stop bit is not set, and updates the I/O counter associated with the logical volume and the processor core in response to accessing the logical volume. Other embodiments are described and claimed.

Abstract: Technologies for quality of service (QoS) management include a computing device having a physical storage volume and multiple processor cores. A management thread reads I/O counters that are each associated with a logical volume and a processor core. The logical volumes are backed by the physical storage volume. The management thread configures stop bits as a function of the I/O counters and multiple QoS parameters. Each stop bit is associated with a logical volume and a processor core. The QoS parameters include minimum guaranteed bandwidth and optional maximum allowed bandwidth for each logical volume. A worker thread reads the stop bit associated with a logical volume and a processor core, accesses the logical volume if the stop bit is not set, and updates the I/O counter associated with the logical volume and the processor core in response to accessing the logical volume. Other embodiments are described and claimed.

Abstract: An apparatus having a cache and a circuit is disclosed. The cache includes a plurality of cache lines. The cache is configured to (i) store a plurality of data items in the cache lines and (ii) generate a map that indicates a dirty state or a clean state of each of the cache lines. The cache also has a write-back policy to a memory. The circuit is configured to (i) check a location in the map corresponding to a read address of a read request and (ii) obtain read data directly from the memory by bypassing the cache in response to the location having the clean state.

Abstract: A storage controller coupled to a host computer is dynamically configured by a device driver executing in the host computer. The storage controller manages a logical volume for the host using a set of flash-based storage devices arranged as a redundant array of inexpensive disks (RAID). The device driver identifies a RAID type for the logical volume and a queue depth from a stream of I/O commands. For a logical volume in RAID 0, the device driver compares the queue depth to a threshold value and configures the storage controller to process the stream of I/O commands with a first path or an alternative path based on a result of the comparison. For a logical volume in RAID 5, the device driver performs a similar comparison and uses the result to direct the storage controller to use a write back or a write through mode of operation.

Abstract: Methods and structure for splitting Input/Output (I/O) for Redundant Array of Independent Disks (RAID) systems. One embodiment is a system that includes a processor of a host, and a memory of the host. The processor and the memory implement a device driver for communicating with a physically distinct RAID controller. The device driver is able to receive an I/O request, from an Operating System of the host, that is directed to a RAID volume. The device driver is further able to determine that the controller includes dedicated circuitry for handling I/O requests directed to a single RAID strip. Responsive to determining that the controller includes such dedicated circuitry, the device driver is able to identify RAID strip boundaries within the received request, and to generate multiple child I/O requests that are each directed to a single strip of the volume and correspond to the identified strip boundaries.

Abstract: A storage controller coupled to a host computer is dynamically configured by a device driver executing in the host computer. The storage controller manages a logical volume for the host using a set of flash-based storage devices arranged as a redundant array of inexpensive disks (RAID). The device driver identifies a RAID type for the logical volume and a queue depth from a stream of I/O commands. For a logical volume in RAID 0, the device driver compares the queue depth to a threshold value and configures the storage controller to process the stream of I/O commands with a first path or an alternative path based on a result of the comparison. For a logical volume in RAID 5, the device driver performs a similar comparison and uses the result to direct the storage controller to use a write back or a write through mode of operation.

Abstract: An apparatus having a cache and a circuit is disclosed. The cache includes a plurality of cache lines. The cache is configured to (i) store a plurality of data items in the cache lines and (ii) generate a map that indicates a dirty state or a clean state of each of the cache lines. The cache also has a write-back policy to a memory. The circuit is configured to (i) check a location in the map corresponding to a read address of a read request and (ii) obtain read data directly from the memory by bypassing the cache in response to the location having the clean state.

Abstract: An apparatus having one or more memories and a controller is disclosed. The memories are divided into a plurality of regions. Each regions is divided into a plurality of blocks. The blocks correspond to a plurality of memory addresses respectively. The controller is configured to (i) receive data from a host, (ii) generate metadata that maps a plurality of host addresses of the data to the memory addresses of the memories and (iii) write sequentially into a given one of the regions both (a) a portion of the data and (b) a corresponding portion of the metadata.

Abstract: An I/O scheduler and a method for scheduling I/O requests to a solid-state drive (SSD) is disclosed. The I/O scheduler in accordance with the present disclosure bundles the write requests in such a form that the write requests in each bundle goes into one SSD block. Bundling the write requests in accordance with the present disclosure reduces write amplification and increases system performance. The I/O scheduler in accordance with the present disclosure also helps increasing the life of the SSDs.