Dprocess on SMPwww.xjtu.edu.cn

Siyuan Ma

Arch

Ft_kthread_queue

User console

Ft daemon

Ft process

Ft event queue

Ft daemon

compare error handler

Ft daemon

Ft event queue

compareerror

sync error handler

syncerror

socketerrorsync

error

syncerror

periodevent

Tell the consolefork a new twin

Tell the console

period event handler

Check ft queue

Report to console

log

close the ft modeKill the error process

Ft daemon cons

central fault handler make it easy to change the ft policy

do not affect the running of ft processes even if it is down

pros Single Point of Failure

more centralization, less fault tolerance

able to improve sort the event queue before handler it, more analysis More option in console Periodic reboot to overcome the Single Point of Failure

User process breakdown

timer

Sync?

Sync?

Sync?

sleep on a queue to wait brother

add a timer

FT Daemon

•User process moniter

•Reboot abnormal process

Process X

Process X’ Code Seg 1

Code Seg 1

Sync 1

Sync 1

Code Seg 2

Code Seg 2

Sync 2

Sync 2

Code Seg 3

Code Seg 3

Sync 3

Sync 3

Sync

remove the timer

Wake up the brother

Sync

Time out?

Brother gone?

Recovery

process x

process x’

Ft daemon

process x’’

sync

synctimeout

handler

wake up sync

double fork

exit

exitfork by process 2

sync

killed by daemon