1. Constructing MRMW Atomic Registers from Safe BitsBy
Adesola Omotayo Yuliang Bao
October 30, 2003

2. Agenda Some Background Info. Problem Statement Model Resources
From here…

3. Some Background Info.
Registers are usually specified in the following format
x,y,z
where x, y and z are the coordinates

4. Coordinate x Coordinate x Safe Regular Atomic read1 read2 read3
write 6
write 5
Domain values: {4, 5, 6}

5. Coordinate y
Coordinate y
Boolean
{0, 1}
Multi-valued
{1…n}

6. Coordinate z Coordinate z Single-Reader Single-Writer (SRSW)
Single-Reader Multi-Writer (SRMW)
Multi-Reader Single-Writer (MRSW)
Multi-Reader Multi-Writer (MRMW)
SRSW
register
MRSW
register
write
read
write
reads
SRMW
register
MRMW
register
writes
read
writes
read

7. Property Serializability
Some different transactions scheduled so that the net effect of their execution is the same as if the transactions have been executed in some serial order are said to be serializable.
WRRW
RRR
WRRWRWRWRRR
RWRW

8. Problem Statement
Efficient construction of a MRMW atomic register from the weak SRSW safe registers

9. Model
Shared memory
MRMW
Multi-valued
Atomic register

10. Resource
Single-Reader
Single-Writer
Boolean
Safe Registers

11. Registers:Hasse Diagram
MRMW,MV,A
MRSW,MV,A
SRSW,B,A
SRSW,MV,A
SRSW,B,S
SRSW,MV,S
MRSW,MV,S
SRSW,MV,R
MRSW,MV,R
MRSW,B,S
MRSW,B,R
O(K)
O(n)
O(m)
O(1)
MRMW,MV,R
SRSW,B,R

12. From here…
Study more to be able to successfully complete the project…

13. Thank you!