?????????????(free())??????

1
???????????????????????????????

• ?????? ?????
• ?? ??

2
????????????????????

• ????????????????????
• ???????(???)????????
• ????????????????????
• ?????????????(free())??????
• ???????????????????
• ????????????????????
• ???????????????????(GC)???

3
??????????????????????

• ?????????? ??????????????????????
• ????????????????????(OS???malloc(), Java
  VM????????)????????
• ????????
• ???????100K?/???????
• GC?????20
• ????????????? ????????????GC???

?????????? ????????? ???????!
4
?????

• ????????????????????????????????
• ????????/GC????????????
• ????????
• ??????????(SMP, DSM)???????
• ????????????
• (??????????????)
• http//www.yl.is.s.u-tokyo.ac.jp/gc/

5
?????????(1)

• ???????? ??????????
• ???????? ????????????
• C/C
• Pthread, Solaris thread??
• ?????1????1????????
• ????????????????????????????

SMP ???????????
DSM ??????????
6
?????????(2)

• Conservative GC????? Boehm et al. 88??????
• BIBOP(Big-bag-of-pages)?????
• ????????????????
• ???????GC
• ???????????GC??
• ??????GC
• ????GC
• ??????????BIBOP????????????????????

7
?????

1. ??????????????
2. ?????????????GC (???)
3. ??????GC??????
4. ????GC (???)

8
Part 1??????????????????????

• (JSPP 2001 ???)

9
?????????????????????(1)

• ??????????????????????????
• ??????? ????
• Libc malloc??????????????

Libc malloc???????

• SGI Origin 2000
• 16byte??????????????????malloc??(???????)
• ???????????????
• free???????

?? ?
10
?????????????????????(2)

• ?????/????????????????
• ???????????????????????????
• ????????? (?????????)
• Larson?98 Vee?99 ????????
• Berger?00 ???????????
• ???????(DSM)?????????????????

11
??????????????????

• ??????????????
• ??????????????????????
• ????????????m???????????????2m
• ???(???????????)???

????????????????
m
thread 1 ???
time
m
thread 2 ???
time
???????? ???
??????
???????
????????????? ????
??
12
???????????????

• ????????
• ?????????????
• ??? (????DSM???)
• ?? ????/????????????????(3?)
• ?????????????????????????????????????
• ???????
• ???????????????????????
• ????????????????
• ???????????? ??????????
• ??????? ???????????????????

13
???????

• LPS(locality-aware page shared)??
• BIBOP(big bag of pages)????????????
• ??????
• 64?????(R10000 195MHz)?25M malloc/s
• 1???????36?
• ?????????????????????????
• ?????????? (k, 1?k??????) ???

14
BIBOP????????

• ???????????????????
• ????????????????????
• ??????????????
• ????????????(????)
• ?????????
• ???????
• ??????????????
• ???????????????
• ????OS????????/GC

free obj list
free page list
heap
15
????????
threads

• All Local(AL)??
• ?????????????
• ? ????????????
• ???????
• Page Shared(PS)??
• ???????? ??????
• ????? ??
• ? ???????
• ???

free obj list
free page list
OS
All-local(AL)
threads
free obj list
free page list
OS
Page-Shared(PS)
16
???? LPS??
threads

• Locality-aware Page Shared (LPS)??
• ????????????? ?????????????
• 1. ????????????????
• 2. ??????????????????
• ??????
• 3a. ??????????????????????
• 3b. ???????OS????

free obj list
free page list
OS
(kmax(l))
k?? ? ?????? k?? ? ?????
?????? (????????)
?????????? (PS???????)
17
????

• ??? DSM??? SGI Origin 2000
• R10000 195MHz 80
• Hypercube network
• ??????16KB
• ??????????????????????????????????????????????????
  ??(first-touch)
• ???????????
• Matmul(???)
• CKY(?????????)
• BH(N???)?????
• C, GC??, StackThreads/MP ?? 99 ??(CKY??)

18
??????????????

• 16byte??????????????
• ???????????????
• free/GC???????

?? ?

• ?????????????malloc?????
• AL/LPS????????????
• 64?????25M?/? (1??????36?, libc 64 ?????54?)

19
????(1) matmul

• ????????????????
• ???1?????????????
• ??????????(????)???
• AL???????????????????
• 10001000???????30?

64???????????

?
20
????(2) matmul???

• LPS/AL?PS??319??

21
????(3) CKY

• ?????????
• ????????????????????????
• ??????????????????????
• 36100?????200???

64???????????
????????? ??????
??
22
????(4) CKY???

• AL/PS?????????
• LPS/AL?PS????5??

23
??

• ??????????????????
• ???????????
• 32??????????????
• CKY?????????10???????
• ?????????????????????
• Matmul??????CKY???????????

?????
16???????????
(IRIX Memory Reference Counter?????)
24
????

• ?????????????????????????
• ???94 KLIC???????????????GC
• Larson?98
• Vee?99 ???????????????
• Berger?00 BIBOP,????????
• Boehm00 BIBOP, ????????????????????????
• ????DSM??????????

25
Part1????

• ??BIBOP???????LPS???
• ????
• ???????? 64?????36?
• ???????
• DSM?????
• ???????????????????????????????

??????
26
Part 2?????????????GC

• (SC97, JSSST????98???)

27
??????GC
time
????
???? GC
??GC ????????
Doligez 93??
??????GC
????GC (Part 4)
Halstead 85??
Cheng 01

• ??????GC??
• ???????????GC??? ? GC?????
• GC??GC??? ? ????????????

28
?????????GC(1)

• GC????????????????
• ????????????????? ? ???????!
• ?????????????????????

29
?????????GC(2)

• ?????????????
• ????????????? (???????)
• ??????? ????????????????????(????????????)???
• ?????????????? ? ?????????????

Lazy task creation Mohr et al. 90???
30
?????????????????

• ???????????????
• ?????????????????????
• DSM???????????????????????

??????
31
????

• ???
• Sun Enterprise 10000 SMP
• Ultra SPARC 250 MHz 64
• 10GB/s??????????
• SGI Origin 2000 DSM
• ?????
• BH (N???)
• Cube (Rubiks Cube?????)
• CKY (?????????) ????

32
???????? BH
60??????????? (Enterprise, BH-pt)

• Barnes-Hut?????????N????????
• ????1 ?????????????????????
• ????2 ??????????? (???O(N log N))
• ?????????????
• ??????????????????????
• 2?????????????
• ????2?????(BH-st)
• ? 1??????????
• ????1,2????(BH-pt)
• 30,000??20??????
• ?????? 50MB??

A
?
33
???????? Cube
60??????????? (Enterprise)

• Rubiks Cube???????
• ??????????????(???????????)
• ?????????????????????
• ?????? 35MB??

???
?????????? ??????????
34
????(1)Enterprise??GC????

• (??????????/?????)???????
• ??????????????????
• 60?????1932??????

35
????(2)Origin??GC????
13?
7?

• Enterprise?????????
• Origin????BH-pt?BH-st??????
• ??????Part3???

36
????

• ??????GC
• Halstead et al. 85 ??????
• Uzuhara 90 Imai et al. 93 ???????????????????
  ??
• Flood et al. 01 ??????????????Copy
  GC?mark-compact GC????

37
Part2????

• ????????????????????GC???
• ???????????????????
• Enterprise 10000 60?????1932??????
• Origin 2000 64?????720??????

38
Part 3??????GC??????

• (??????????????, IPDPS2001???)

39
???????????GC??????

• Part2????????GC??????
• SMP/DSM???????????
• ?????????
• ???????
• ????????????????????????
• GC??????????????????
• ???????
• ????????????
• ????????????(????)

40
????????

• ??????????????????????
• ???????????????
• ?????????????????
• ??????????????????DSM???

Enterprise 10000 (SMP)
Origin 2000 (DSM)
41
????????(1)

• ?? GC??????????????
• ?? P????????GC??????
• ??????????????????????
• Live??????????????????????
• 1????????CPU????????????????
• CPU?? ? Live??????????
• ???????? ? ??????????????????????
• ?????

42
????????(2)
?????????????
???
???
CPU??
T1
TP
????GC??
??????? ?????
????????
Q1
QP
TPM
TPM TP QPMP/P
MVA
??????? ???
MP
M1
???? 4.3.1 ??? TPM TP QPMP ? TPM TP
QPMP / P

• ??????????????????????
• ??????/????????TLB???

43
??????????

• ?????????????????????????????
• 1/P???????????????
• ??????????????????
• ??????????????? (cf. LoPC???Frank et al.97)
• ??????????????
• ????????? CPU?Mem?CPU
• ??????2???????????????
• ???????????????????????
• ?????????????????????

44
?????????????
?????
? ??????????? ???????????? ???????????
??????
SL
SO
SL

• SL ????????SO ??????????????
• ??????? MP 2 SL SO ??????

????????????
??????????????????????????
????????? DSM????!
45
???????????(1)
????
????
B
B
A
A
PE1
PE1
PE2
PE3
??????????????????????????????????? ? ??????
46
???????????(2)
???? Q1 4
????????
???? QP Q148
???????
????????
??????????

• ?????????????????
• QP Q1 (????????) (?????????????)

???????? P log(live-objects)
???????????????
47
???? ????????
BH-st
Cube
E10000 SMP
O2000 DSM
Real Pred (full) Pred (no contention) Pred (no
miss incr.)

• BH(DSM)?????????????
• Cube????????????
• ?????738

48
????

• LogP???Culler et al. 93
• latency, overhead, gap(bandwidth), processor
• LoPC???Vernon et al. 97
• active message???????????????
• ??????????????
• Portable Parallel Memory Frigo 99
• ?????????????????
• ?????????? ?underestimate
• ??????(???? x steal??)????? ?overestimate

49
Part3????

• ??GC???????????????
• ??????????????P?????????????
• ?????????????????????
• ?????????????(????)
• ???????????????
• ?????????????????
• GC??????????(????)
• ?????
• ??????(???????????????????)
• ?????????????

50
Part 4????GC
51
????GC

• ??????????????????????GC?????????? ? ??GC?????
• ????????????????????????????
• GC?????????????
• GC?????

????GC
52
???? v.s. ??????

• ????GC?????
• ? ???????
• ?????????????
• ???/GC???????
• ? ????????GC?????
• ? ?????????????

?????????
?????????
53
????GC??????
??????GC
GC cycle
??????
??????
??????
?????? ????GC
GC cycle

• Mostly parallel GCBoehm 91????
• ??????
• Incremental update??????Dijkstra 78????
• ?????????????????????????

54
??????????

• ?????????????????GC?????
• ??????????

• Incremental update?????????
• ?????? ????????????
• ?????? ???????
• ??? ????????????GC???
• ??????
• A ??????????????
• B ???
• ?????? (?????????)
• ???????A?????(????)

55
?????????

• 2????????????
• ????????????????
• ? ??????????
• ? GC?????????????
• ????????????????
• ?????
• ?????????????????????????????

56
????(1) ????
BH-pt
Cube
CKY
E10K
O2K

• ??????GC??????GC(VM???)???
• E10000 8????????????????1.73.2????
• ????????????????????????????

57
????(2) ????
BH-pt
Cube
CKY
E10K
O2K

• ????GC???????GC???????????(??1.9?)
• VM??????????????????????????
• ???????????????????VM???

58
???????

• ????????GC?????????????????????????????
• ????????????????????
• ???????????????

BH-pt/E10K
CKY/E10K
Cube/E10K
BH-pt/O2K
CKY/O2K
Cube/O2K
59
????

• ????????GC/??GC
• Steele 75 Dijkstra 78 Baker 78 Yuasa 90
  Doligez 93
• GC????????????????
• ????????????1?????GC????????????
• ????GC Cheng et al. 01
• ???????GC??????????????
• ML???????????????????
• ? ?????????????????????

60
Part4????

• ???????????GC???
• ???????????????????GC???
• ???????
• ?????????????????????
• 2??????????????????
• ????????????????????????
• ?????
• ?????????
• ???????(Snapshot-at-beginning??)????
• ????
• GC???/??????
• ????????????????

61
??????

• ????????????????????????????????????
• ??????????????
• ????????????????????????? (Part 1)
• ???????????GC???????GC (Part 2, 4)
• ?????????????????
• ????????????? (Part 1)
• ???????????
• ?????????????? (Part 1)
• GC??????? (Part 4)

62
?????????????????

• ??????????
• Region analysis
• ???GC
• ??????
• ?????????????GC?????
• ??????????????
• Escape analysis ? ????????????/???????????
• ??????????????????????
• ????????????????GC??????
• ?????/???????????

63

• ??????????