The Dirty-Block Index

Vivek SeshadriAbhishek Bhowmick ∙ Onur Mutlu

Phillip B. Gibbons ∙ Michael A. Kozuch ∙ Todd C. Mowry

Today – 4:15PM – Session 3A

Mismatch: Representation and Query

ABC

Z

…

Sorted by Title

Get all the books

written by author X

Breadth FirstSearchList all edges

adjacent to

vertex ‘a’

0 1 0 0 01 0 1 1 00 1 0 0 00 1 0 0 10 0 0 1 0

ac

bd

e

Mismatch: Representation and Query

Tag TagTag TagTag TagTag Tag

DDDD

DDDD

Cache Tag Store

Dirty Bit

Is block

X dirty?

List all dirty

blocks of DRAM row R.

Mismatch: Representation and Query

Tag TagTag TagTag TagTag Tag

Cache Tag Store

DBI

Dirty-Block Index

Is block

X dirty?

List all dirty

blocks of DRAM row R.

DBI

Many Optimizations1.DRAM-aware writeback2.Bypassing cache lookups3.Reducing ECC overhead4.Efficient cache flushing5.Load balancing memory accesses6.Bulk DMA7.Efficient write scheduling...

Many Optimizations1.DRAM-aware writeback2.Bypassing cache lookups3.Reducing ECC overhead4.Efficient cache flushing5.Load balancing memory accesses6.Bulk DMA7.Efficient write scheduling...

DBI31% performance over

baseline

6% over best previous

mechanism

8% cache area

reduction

The Dirty-Block Index

Vivek SeshadriAbhishek Bhowmick ∙ Onur Mutlu

Phillip B. Gibbons ∙ Michael A. Kozuch ∙ Todd C. Mowry

Today – 4:15PM – Session 3A