Browse Prior Art Database

DCATCH between list entry

IP.com Disclosure Number: IPCOM000015753D
Original Publication Date: 2002-Apr-25
Included in the Prior Art Database: 2003-Jun-21
Document File: 1 page(s) / 26K

Publishing Venue

IBM

Abstract

Disclosed is a method to improve drive write performance in AT HDD.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

DCATCH between list entry

Disclosed is a method to improve drive write performance in AT HDD.

--- part 1 ---

If command finished as below sequence

Write LBA 0, Len 1
Write LBA 2, Len 1
Write LBA 1, Len 1

Buffer data will be pushed as below

                          DCPAGE (=HPAGE)
|---------|---------|---------|

LBA 0 LBA 2 LBA 1

These data will be written by List Write function as LBA0 -> LBA1 -> LBA2. In
this case DCPAGE indicates last HPAGE , so media write operation will be
stoped after LBA1 data write is finished. To avoid this DCATCH , ignore DCATCH
when list entry (in this case , LBA2) is still remain.

--- part 2 ---

 Entry1 Entry2
|-----| |-------|

A
|

+--- HPAGE = DCPAGE

As above case , microcode is waiting for transfer complete of 1st sector of
Entry2. Because current H/W cannot issue DCATCH at the end of Entry1 as above
case.

H/W knows Entry2's 1st page(=NEXT DPAGE) at end of Entry1, so H/W can issue
DCATCH by compareing NEXT DPAGE with DCPAGE.

By using 2 methods

1. Unnecessary DCATCH can be avoided.
2. Microcode don't have to check if 1st sector of Entry2 is completed or not.

So, total performace will be improve.

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