Electrical computers and digital data processing systems: input/ – Input/output data processing – Input/output data buffering
Reexamination Certificate
2009-10-30
2011-11-08
Shin, Christopher B (Department: 2181)
Electrical computers and digital data processing systems: input/
Input/output data processing
Input/output data buffering
C710S040000, C710S107000, C710S244000, C709S232000, C370S412000
Reexamination Certificate
active
08055817
ABSTRACT:
Computer program products and methods for efficient handling of queued-direct input/output (QDIO) requests and completions at an adapter in communication with an I/O device are provided. A method includes accessing a queue with one or more storage block address lists (SBALs), where each SBAL includes a plurality of storage block address list entries (SBALEs) and is associated with an SLSB. The method further includes reading an SBAL count in one of the SBALEs, where the SBAL count indicates a number of the SBALs forming an I/O request to the I/O device. In response to determining that the SBAL count is greater than one, a number of the SBALs from the queue and associated SLSBs equivalent to the SBAL count are prefetched without waiting for a notification of completion of each of the SBALs forming the I/O request, and states of the associated SLSBs transition from adapter-owned to program-owned.
REFERENCES:
patent: 6345324 (2002-02-01), Baskey et al.
patent: 6401145 (2002-06-01), Baskey et al.
patent: 2003/0208635 (2003-11-01), Stevens
patent: 2004/0080512 (2004-04-01), McCormack et al.
patent: 2004/0167961 (2004-08-01), Jain et al.
patent: 2005/0289246 (2005-12-01), Easton et al.
patent: 2010/0223392 (2010-09-01), Pond et al.
I. Adlung, et al., FCP for the IBM eServer zSeries systems: Access to distributed storage, IBM J. Res. & Dev. vol. 46 No. 4/5 Jul./Sep. 2002, 16 pages.
M.E. Baskey, et al., zSeries features for optimized sockets-based messaging: HiperSockets and OSA-Express, IBM J. Res. & Dev. vol. 46 No. 4/5 Jul./Sep. 2002, 11 pages.
Higgs Raymond
Kuch George P.
Ratcliff Bruce H.
Sittmann, III Gustav E.
Stevens Jerry W.
Cantor & Colburn LLP
Chiu Steven
International Business Machines - Corporation
Shin Christopher B
LandOfFree
Efficient handling of queued-direct I/O requests and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Efficient handling of queued-direct I/O requests and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Efficient handling of queued-direct I/O requests and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4275218