摘要:
Method and apparatus for adaptive arrangement of data on storage media, such as in a multi-device storage array across which data are stored. A virtual hot space is formed to store frequently accessed data. The virtual hot space comprises at least one hot data zone which extends across storage media of a plurality of arrayed storage devices over a selected seek range less than an overall radial width of the media. The frequently accessed data are stored to the hot data zone(s) in response to a host level request, such as from a host level operating system (OS) or by a user which identifies the data as frequently accessed data. Alternatively or additionally, access statistics are accumulated and frequently accessed data are migrated to the hot data zone(s) in relation thereto. Lower accessed data sets are further preferably migrated from the hot data zone(s) to another location of the media.
摘要:
A system which provides a completely redundant configuration including dual Fibre Channel fabric links interconnecting each of the components of two data storage sites, wherein each site comprises a host computer and associated data storage array, with redundant array controllers and adapters. The array controllers perform a command and data logging function which stores all host write commands and data ‘missed’ by the backup storage array during a situation wherein the links between the sites are down, the remote site is down, or where a site failover to the remote site has occurred. Log units are used to store, in order, all commands and data for every transaction which was ‘missed’ by the backup storage array when one of the above system error conditions has occurred. The system provides rapid and accurate recovery of backup data at the remote site by sending all logged commands and data from the logging site over the link to the backup site in order, while avoiding the overhead of a full copy operation.
摘要:
Methods and apparatus for precisely applying finely spaced grid lines to an existing shaft on site include, in a first embodiment, attachment of a master grid line carrier to the shaft. In preferred embodiments, the carrier is helically wrapped about the shaft or mated at a diagonal seam across the carrier. Photosensitive material is then applied to the shaft at one or more axial locations. The shaft is rotated and passage of the grid lines on the master is sensed. A light source synchronized to the detection of the master grid lines exposes the photosensitive material as the shaft is rotated to create identical sets of finely spaced grid lines at multiple axial locations on the shaft. The invention also includes a synchronous laser Dopper velocimeter (SLDV) which accurately senses the passage of the lines on the shaft. An extremely accurate torsional interferometer can be constructed using the SLDVs.
摘要:
A method and apparatus for detecting the presence of speech telecommunications tones on a communication line includes a voltage divider for ranging signals received from a communication line, a C-weight filter which receives the ranged signals and simulates the frequency response of the human ear to noise, an RMS-to-DC converter for producing a DC signal from the output of the C-weight filter, an A/D converter for converting the DC signal into digital data and a microprocessor for receiving the digital data and controlling the invented apparatus. Energy samples obtained from an accessed telephone line are, in software, assigned various weights in accordance with the level of energy found in each sample. The microprocessor, under software control, uses the weights actually assigned to determine whether the energy sampled is due to speech or a tone.
摘要:
Method and apparatus for adaptive arrangement of data on storage media, such as in a multi-device storage array across which data are stored. A virtual hot space is formed to store frequently accessed data. The virtual hot space comprises at least one hot data zone which extends across storage media of a plurality of arrayed storage devices over a selected seek range less than an overall radial width of the media. The frequently accessed data are stored to the hot data zone(s) in response to a host level request, such as from a host level operating system (OS) or by a user which identifies the data as frequently accessed data. Alternatively or additionally, access statistics are accumulated and frequently accessed data are migrated to the hot data zone(s) in relation thereto. Lower accessed data sets are further preferably migrated from the hot data zone(s) to another location of the media.
摘要:
Method and apparatus for logging and analyzing event flows associated with execution of a service request in a software system, such as a computer-based system comprising a multi-disc data storage array. Execution of the service request results in a plurality of events carried out by multiple layers of the software system. A global event log accumulates a corresponding plurality of entries which associates each of the events carried out by the multiple layers. An event trace facility preferably accesses the global event log to provide a sequence of the entries corresponding to the service request, such as in a tree structure or time sequence order displayed by a graphical user interface. A log manager preferably controls operation of the global event log. Entries in the global event log are preferably entered sequentially for each ongoing process, and each entry preferably includes an identifier that identifies the associated service request.
摘要:
Method and apparatus for wave flushing cached writeback data to a storage array. A cache manager operates to initiate a wave flushing operation whereby sets of writeback data in a cache memory are sequentially written to each of a plurality of logical groups radially concentric with respect to the storage medium. During the wave flushing operation, a write transducer is radially advanced across the medium in a single radial direction across boundaries between immediately adjacent groups. The write operations thus form a traveling wave across the medium, analogous to a wave in a sports stadium formed by spectators standing up and sitting down in turn. Each logical group preferably corresponds to a selected transducer seek range, such as an associated RAID stripe. Seeks are preferably bi-directional within each group, and uni-directional between adjacent groups. A dwell time (service time interval) for each group can be constant, or adaptively adjusted.
摘要:
A system detects relative movement between an optical sensor unit and a set of finely spaced, parallel grid lines. Unlike prior optical line detection systems, each set of lines is applied to a surface of an object at an angle relative to movement between the optical sensor unit and the object. The system is particularly useful for monitoring rotating members, such as shafts, but is also useful with linearly moving members. In a preferred shaft monitoring application, a plurality of optical units are provided, with a plurality of corresponding sets of parallel lines at different angles on the shaft. Signal output phase differences between the optical units are compared to precisely determine movement of the shaft in seven directions of freedom, including rigid body displacement components along three translational and three rotational axes, and shaft twist. The differentially angled sets of lines may be spaced axially along the shaft or other object, or a plurality of angled line sets may be superimposed in a single location as a set of cross-hatched lines.
摘要:
An improved cleaning apparatus for textile machines, of the type that includes overhead trackways and cleaner units propelled along the trackways, is provided with an arrangement for automatically removing accumulated lint from the cleaner units while cleaner units are moving along the trackways. During cleaning of the textile machines, lint is stripped from lint-laden intake air by conical screens respectively associated with the depending suction tubes of the cleaner unit. Hinged doors are arranged above and below each conical lint-stripping screen, and all four of these doors are opened at a lint collection station so that the accumulated lint may be rapidly withdrawn from the smaller ends of the screens directly into suction hoods. Mechanical door-actuating mechanisms are provided so that the cleaner unit is automatically doffed when moving in one direction through the lint removal station and so that the cleaner unit can, dependent on the desired trackway configuration, be driven in the opposite direction through the lint removal station without necessarily opening the doors.