Patents by Inventor Hiroyuki Kitajima
Hiroyuki Kitajima has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 6938125Abstract: A disk storage system has a control unit having a plurality of external ports connectable to a mirrored disk including two disks to which write data is written. When the control unit receives two read requests issued from a processor to the disk unit group, a first read operation is performed to read data requested by the first read request from one of the disks and a second read operation is performed to read data requested by the second read request from the other one of the disks. Also, a first transferring operation is performed to transfer data read by the first read operation to one external port of the control unit and a second transferring operation is performed to transfer data read by the second read operation to another external port of the control unit. Further, the data read by the two read operations is transferred to the processor via the external ports.Type: GrantFiled: August 6, 2003Date of Patent: August 30, 2005Assignee: Hitachi, Ltd.Inventors: Akira Yamamoto, Takao Satoh, Shigeo Honma, Yoshihiro Asaka, Yoshiaki Kuwahara, Hiroyuki Kitajima
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Publication number: 20050180227Abstract: According to one aspect of the present invention, a booster circuit comprises a charge pump, a voltage supply section reducing a power supply voltage and supplying a voltage to the charge pump through an output metal-oxide-semiconductor (MOS) transistor of an operational amplifier and a drive MOS transistor maximizing a drive capacity of the output MOS transistor of the operational amplifier.Type: ApplicationFiled: February 10, 2005Publication date: August 18, 2005Applicant: NEC Electronics CorporationInventor: Hiroyuki Kitajima
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Patent number: 6874101Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: GrantFiled: February 20, 2003Date of Patent: March 29, 2005Assignee: Hitachi, Ltd.Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo
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Publication number: 20050050267Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: ApplicationFiled: September 22, 2004Publication date: March 3, 2005Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo
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Publication number: 20040177220Abstract: A storage system stores multiple copies of data on physical storage implemented, for example, with multiple disk units. Input/output read requests are received from host systems and distributed in a manner that allows parallel read operations to be conducted over the multiple disk units of the physical storage.Type: ApplicationFiled: March 11, 2004Publication date: September 9, 2004Applicant: Hitachi, Ltd.Inventors: Akira Yamamoto, Takao Satoh, Shigeo Honma, Yoshihiro Asaka, Yoshiaki Kuwahara, Hiroyuki Kitajima
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Patent number: 6757839Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: GrantFiled: December 16, 2002Date of Patent: June 29, 2004Assignee: Hitachi, Ltd.Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo
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Patent number: 6728832Abstract: A method of respectively reading and writing data to and from a plurality of physical disk units in response to I/O requests from a host computing system includes establishing a logical disk group having a number of logical disk elements, mapping each of the logical disk elements to corresponding physical disk units, receiving from the host computing system an I/O request for data to select a one of the number of logical disk elements, accessing the physical disk unit corresponding to the selected one logical disk to access for the data, and transferring the accessed data to the host computing system.Type: GrantFiled: March 20, 2001Date of Patent: April 27, 2004Assignee: Hitachi, Ltd.Inventors: Akira Yamamoto, Takao Satoh, Shigeo Honma, Yoshihiro Asaka, Yoshiaki Kuwahara, Hiroyuki Kitajima
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Publication number: 20040078645Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: ApplicationFiled: December 16, 2002Publication date: April 22, 2004Applicant: Hitachi, Ltd.Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo
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Publication number: 20040030828Abstract: In an information processing system having a data processing apparatus, a control unit for a cache memory, and a storage unit for storing a record, respectively interconnected together, wherein when the control unit receives from the data processing apparatus a write request for a record to be written and if the record to be written is not being stored in the cache memory, the control unit receives a data to be written in the object record from the data processing apparatus and stores the received data in the cache memory. After notifying the data processing apparatus of a completion of a data write process, the control unit checks if the object record in which the data stored in the cache memory is being stored in the storage unit, if the object record is being stored in the storage unit, the data in the cache memory is written in the storage unit, and if not, the data in the cache memory is not written and such effect is notified to the data processing apparatus.Type: ApplicationFiled: August 4, 2003Publication date: February 12, 2004Applicant: Hitachi, Ltd.Inventors: Akira Yamamoto, Shigeo Homma, Yoshihiro Asaka, Yoshiaki Kuwahara, Akira Kurano, Masafumi Nozawa, Hiroyuki Kitajima
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Publication number: 20040030829Abstract: The control unit arbitrarily with respect to the CPU, including according to an algorithm that is independent of the request a disk unit among the disk units that are inactive when the control unit receives an input/output request involving either read or staging. For a write request from the CPU, the control unit selects a specific disk unit in the disk unit group for the immediate writing of data. In the second kind of load distribution a disk unit is selected to execute read and staging other than the above-mentioned specific disk.Type: ApplicationFiled: August 6, 2003Publication date: February 12, 2004Applicant: Hitachi, Ltd.Inventors: Akira Yamamoto, Takao Satoh, Shigeo Honma, Yoshihiro Asaka, Yoshiaki Kuwahara, Hiroyuki Kitajima
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Patent number: 6631443Abstract: A disk storage system has a control unit having a plurality of external ports connectable to a mirrored disk including two disks to which write data is written. When the control unit receives two read requests issued from a processor to the disk unit group, a first read operation is performed to read data requested by the first read request from one of the disks and a second read operation is performed to read data requested by the second read request from the other one of the disks. Also, a first transferring operation is performed to transfer data read by the first read operation to one external port of the control unit and a second transferring operation is performed to transfer data read by the second read operation to another external port of the control unit. Further, the data read by the two read operations is transferred to the processor via the external ports.Type: GrantFiled: July 18, 2000Date of Patent: October 7, 2003Assignee: Hitachi, Ltd.Inventors: Akira Yamamoto, Takao Satoh, Shigeo Honma, Yoshihiro Asaka, Yoshiaki Kuwahara, Hiroyuki Kitajima
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Publication number: 20030126495Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: ApplicationFiled: February 20, 2003Publication date: July 3, 2003Applicant: Hitachi, Ltd.Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo
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Patent number: 6532549Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: GrantFiled: September 21, 2001Date of Patent: March 11, 2003Assignee: Hitachi, Ltd.Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo
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Patent number: 6518804Abstract: A semiconductor integrated circuit device with a high switching speed of an internal power source voltage supplied via an operational amplifier, when said internal power source voltage is output from a switching circuit, is provided. As input signal Vin goes from “L” level to “H” level, MOSFET 21 in switching circuit 20 turns on. At this point, upon the rising edge of input signal Vin to the “H” level, a one shot pulse is supplied to the gate of MOSFET 31 from one-shot-pulse generating circuit 32, and MOSFET 31 turns on. As MOSFET 31 turns on, electric potential at the gate of MOSFET 14, which is included in operational amplifier 13, becomes “L” level, MOSFET 14 turns on completely flowing electric current quickly from external power source voltage Vcc to a capacitive load via MOSFET 14 and MOSFET 21, and output voltage Vout of switching circuit 20 climb up with a steeply-rising waveform.Type: GrantFiled: March 6, 2002Date of Patent: February 11, 2003Assignee: NEC CorporationInventors: Hirokazu Kawagoshi, Hiroyuki Kitajima
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Publication number: 20020125922Abstract: A semiconductor integrated circuit device with a high switching speed of an internal power source voltage supplied via an operational amplifier, when said internal power source voltage is output from a switching circuit, is provided. As input signal Vin goes from “L” level to “H” level, MOSFET 21 in switching circuit 20 turns on. At this point, upon the rising edge of input signal Vin to the “H” level, a one shot pulse is supplied to the gate of MOSFET 31 from one-shot-pulse generating circuit 32, and MOSFET 31 turns on. As MOSFET 31 turns on, electric potential at the gate of MOSFET 14, which is included in operational amplifier 13, becomes “L” level, MOSFET 14 turns on completely flowing electric current quickly from external power source voltage Vcc to a capacitive load via MOSFET 14 and MOSFET 21, and output voltage Vout of switching circuit 20 climb up with a steeply-rising waveform.Type: ApplicationFiled: March 6, 2002Publication date: September 12, 2002Applicant: NEC CorporationInventors: Hirokazu Kawagoshi, Hiroyuki Kitajima
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Publication number: 20020023240Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: ApplicationFiled: September 21, 2001Publication date: February 21, 2002Applicant: Hitachi, Ltd.Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo
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Patent number: 6327673Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: GrantFiled: August 22, 2000Date of Patent: December 4, 2001Assignee: Hitachi, Ltd.Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo
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Publication number: 20010023463Abstract: A storage system stores multiple copies of data on physical storage implemented, for example, with multiple disk units. Input/output read requests are received from host systems and distributed in a manner that allows parallel read operations to be conducted over the multiple disk units of the physical storage.Type: ApplicationFiled: March 20, 2001Publication date: September 20, 2001Inventors: Akira Yamamoto, Takao Satoh, Shigeo Honma, Yoshihiro Asaka, Yoshiaki Kuwahara, Hiroyuki Kitajima
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Patent number: 6148367Abstract: In allocating an area of a cache memory to each storage unit, proper allocation of the cache memory is made to each storage unit. If the amount of write-after data becomes equal to or more than a threshold value, an allocation limit is set to each disk unit. If CPU issues a data write request requiring the amount of data equal to or more than the allocation limit, the data write request is held in a wait state until the amount of write-after data becomes less than the allocation limit. Therefore, the allocation amount to the disk unit becomes neither too large nor too small. In this manner, proper allocation of the cache memory to each disk unit can be realized.Type: GrantFiled: December 24, 1996Date of Patent: November 14, 2000Assignee: Hitachi, Ltd.Inventors: Toshiaki Tsuboi, Akira Yamamoto, Shigeo Honma, Yoshihiro Asaka, Koji Ozawa, Hiroyuki Kitajima, Michio Miyazaki
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Patent number: 6145091Abstract: When receiving a write request from a processor, a control unit checks the condition of existence (or the presence/absence) in a cache for information necessary for generation of an updated value of a parity record, receives write data and reports the completion of the write request to the processor. In asynchronism with the write request from the processor, the control unit performs a load process for that information among the information necessary for generation of the updated value of the parity record which may be prepared in asynchronism with the write request from the processor and a write after process for the updated value of the parity record.Type: GrantFiled: February 22, 1999Date of Patent: November 7, 2000Assignee: Hitachi, Ltd.Inventors: Akira Yamamoto, Hiroyuki Kitajima, Kouji Arai, Yoshihisa Kamo