figure 3. fasttrack race detection algorithm and its comparison to Djit+.

Fasttrack State:

Ct : VC Lm : VC Wx : Epoch Rx : Epoch  VC

Djit+ State: Ct : VC Lm : VC Wx : VC Rx : VC

When Thread t performs rd(t, x):
[Ft reaD same epoch]
if Rx = Et then
skip
endif

63.4% oF reaDs

82.3% of all Operations

[Djit+ reaD same epoch]
if Rx(t) = Ct(t) then
skip
endif

78.0% oF reaDs
[Ft reaD shareD]
if Rx ∈ VC then
assert Wx  Ct
Rx (t) := Ct(t)
endif

20.8% oF reaDs [Ft reaD exclusive]

15.7% oF reaDs
[Djit+ reaD]
if Rx(t) ≠ Ct(t) then
assert Wx  Ct
Rx(t) := Ct(t)
endif

22.0% oF reaDs [Ft reaD share]

0.1% oF reaDs

When Thread t performs wr(t, x):
[Ft write same epoch]
if Wx = Et then
skip
endif

71.0% oF writes
[Ft write exclusive]
if Rx ∈ Epoch then
assert Rx  Ct
assert Wx  Ct

[Ft write shareD]

if Rx ∈ VC then
assert Rx  Ct
assert Wx  Ct
Wx := Et
Rx := ⊥e
endif

28.9% oF writes

0.1% oF writes

14.5% of all Operations

[Djit+ write same epoch]
if Wx(t) = Ct(t) then
skip
endif

[Djit+ write]
if Wx(t) ≠ Ct(t) then
assert Wx  Ct
assert Rx  Ct Wx(t) := Ct(t)
endif

71.0% oF writes

29.0% oF writes