Browse Prior Art Database

Optional Row Hold to Tune for Optimum Performance

IP.com Disclosure Number: IPCOM000103253D
Original Publication Date: 1990-Sep-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 48K

Publishing Venue

IBM

Related People

Hardell WR, Jr: AUTHOR

Abstract

Disclosed is a means to dynamically or statically select whether the memory cards should hold the DRAMs in page mode or static column mode when no access is pending. This can be used to get the best performance from the memory subsystem.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 79% of the total text.

Optional Row Hold to Tune for Optimum Performance

      Disclosed is a means to dynamically or statically select
whether the memory cards should hold the DRAMs in page mode or static
column mode when no access is pending.  This can be used to get the
best performance from the memory subsystem.

      Most of the DRAMs manufactured today have page mode and/or
static column mode.  The row address can be held in the DRAMs for
multiple accesses.  Then only a column address needs to be sent to
the DRAMs after the first access.  If most of the accesses to a bank
of memory are to the same row address as the last access to that
bank, then it is advantageous to keep the DRAMs in page mode or
static column mode. However, if most of the accesses to a bank of
memory are to a different row address than the last access to that
bank, then it is inefficient to keep the DRAMs in page mode or static
column mode.

      With this method the page mode/static column mode can be
dynamically or statically selected for the best memory performance.
For the static method there could be a I/O configuration register
with a bit indicating whether the memory controllers should hold the
last row address to the DRAM chips (keep them in page mode or static
column mode). A program that will perform many string searches might
want to set the row hold active.  While a program that works with
large matrices might want to set row hold inactive.

      For the static configuration, after a n...