Electrical computers and digital processing systems: memory – Storage accessing and control – Hierarchical memories
Patent
1995-11-13
1999-01-12
Swann, Tod R.
Electrical computers and digital processing systems: memory
Storage accessing and control
Hierarchical memories
711100, 711113, 711137, 711141, 711144, G06F 1200
Patent
active
058601058
ABSTRACT:
An NDIRTY cache line lookahead technique is used to expedite cache flush and export operations by providing a mechanism to avoid scanning at least some cache lines that do not contain dirty data (and therefore will not have to be exported). The exemplary cache organization uses one-line lookahead where each cache line but the last has associated with it an NDIRTY bit that indicates whether the next cache line contains dirty data. For cache flush and export operations, when a cache line (N) is read to check for dirty data that must be exported, the NDIRTY bit for that cache line is also tested to determine whether the next cache line (N+1) contains dirty data--if the NDIRTY bit is clear, indicating that the next cache line is clean, then that line is skipped and the scan proceeds with the line after that (N+2). This exemplary one-line lookahead implementation is readily extendible to N-line lookahead. The cache line lookahead technique reduces the number of cache line accesses required during flush/export operations, with the attendant advantages of reduced flush/export penalty cycles and power, thereby improving overall system performance.
REFERENCES:
patent: 5325503 (1994-06-01), Stevens et al.
patent: 5471602 (1995-11-01), DeLano
patent: 5524234 (1996-06-01), Martinez, Jr. et al.
patent: 5537573 (1996-07-01), Ware et al.
patent: 5551000 (1996-08-01), Tan et al.
patent: 5555379 (1996-09-01), Silla
patent: 5555398 (1996-09-01), Raman
patent: 5557769 (1996-09-01), Bailey et al.
patent: 5623635 (1997-04-01), Chen et al.
Burchfield Mark E.
Fourcroy Antone L.
French Robert W.
McDermott Mark W.
Mendyke Xiaoli Y.
National Semiconductor Corporation
Swann Tod R.
Tzeng Fred. F.
Viger Andrew S.
LandOfFree
NDIRTY cache line lookahead does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with NDIRTY cache line lookahead, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and NDIRTY cache line lookahead will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1525128