Memory-centric System Interconnect Design with Hybrid Memory Cubes
The Impact of Operating System Structure on Memory System...
Transcript of The Impact of Operating System Structure on Memory System...
![Page 1: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/1.jpg)
TheImpactofOperatingSystemStructure
onMemorySystemPerformance
ACMSIGOPS,1994
J.BradleyChen(CarnegieMellonUniversity),BrianN.Bershad(University ofWashington)
SanghoonHan,ByeonghunHyeon,Gyusun Lee
![Page 2: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/2.jpg)
Previousworks
• Thispaperisabouttracing
• Oldworks?• Memorysystemstructure• Multiprocessors• Subcomponentofthememorysystem
• HowaboutdifferentOSstructure?
2
![Page 3: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/3.jpg)
Thetwosystemstructures
• SystemcallvsIPC
• Memory사용패턴이다를것
• Systemstructure에따라성능에영향을
미치는원인이다를수있다.3
Monolithic Micro-kernel
![Page 4: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/4.jpg)
Wanttodo
• Memorystructure내에서시간을어떻게
소모하는지측정 (가능한한적은오차로)
• 두 system간차이를비교
• 7assertions이 정말맞는지확인
4
![Page 5: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/5.jpg)
Target
• OS• Ultrix(monotonic)• Mach3.0(microkernel)withCMU’sUNIXserver• Botharederived from3.2BSDUNIX
• Machine• DECstation 5000/200• Because itcanrunbothOS
• 13개의 programworkload
5
![Page 6: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/6.jpg)
Progress
• Modifyexecutionfile• 어떤이유로얼마나시간을보내는지• 어떤주소에접근하는지
•결과 :2배크고 15배느려진 program• 결과를믿을수있는지?• 오차를줄이는법?
6
![Page 7: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/7.jpg)
Minimizedistortion
1.Memorydilation• 이전보다메모리를많이사용할것이다• 실행양상이달라질수있다 (더많은 pageout)• 매우큰 physicalmemory를사용하자• 대신 TLB(user)는 simulation을통해서구현
2.Timedilation• 상대적으로외부환경이 15배빨라진효과• Clock도 15배빨리들어온다 (systemclock을 1/15로늦춤)• I/O속도가빨라진다 (idlethread가적게동작한다)• Idle상태에서보낸시간 x15
7
![Page 8: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/8.jpg)
Minimizedifference
3.Differentpagemappingstrategy• Ultrix:deterministic,Mach:random• Itisimportant• Useddeterministicstrategy
Because,• 실험진행상황을다시재현해보기좋다• 두시스템간차이를줄일수있다.
8
![Page 9: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/9.jpg)
Result(Table)
9
Numberofinstructions,cachemisses
![Page 10: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/10.jpg)
WhatisMCPI?
• MemoryCyclesPerInstruction
• MCPI= CPUstallcyclesduetothememorysystemInstruction
• Onlyincludenon-idleinstructions
• Canverifyresultwiththis.
10
![Page 11: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/11.jpg)
Result(MCPI)
11
![Page 12: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/12.jpg)
Verification
• Assumption• IdleloopCPI=1
• Thenthetotalcycle={Idleinstruction}+{non-idleinstruction}x{1+MCPI}
• Example(gcc)• Cycles=63684000+29318000x(1+0.434)
=105726012• Runtime=Cycles/Clockspeed(25Mhz)
=4.22seconds
12
![Page 13: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/13.jpg)
Comparingtwosystems
13
Ultrix에서의 diskI/O가더많았다.Mach3.0이 demandpaging을지원하기때문
![Page 14: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/14.jpg)
Comparingtwosystems
14
![Page 15: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/15.jpg)
Comparingtwosystems
15
User SystemWorkload Ultrix Mach Difference Ultrix Mach Difference
sed 4335.04 4347.28 12.24 1368.96 3415.72 2046.76egrep 41545.92 41876.97 331.05 1731.08 3152.03 1420.95yacc 30831.06 31085.1 254.04 1967.94 3453.9 1485.96gcc 22868.04 23000.96 132.92 6449.96 12938.04 6488.08
compress 13685.76 13748.94 63.18 3210.24 6177.06 2966.82ab 582720.4 587104.3 4383.84 287011.6 611067.7 324056.16
espresso 132677.3 132293.8 383.54 2707.7 5512.24 2804.54lisp 1249386 1251087 1700.43 38640.81 25532.38 13108.43
equtott 1400225 1403689 3464.01 14143.69 14178.68 34.99fpppp 244220.4 244588.1 367.7 21236.56 18409.86 2826.7doduc 318111.8 318844 732.23 3213.25 6507.02 3293.77liv 22317.76 22351.32 33.56 690.24 1426.68 736.44
tomcatv 1985646 1985534 111.87 20057.03 20055.9 1.13
Non-idleSysteminstruction수차이가크다.
![Page 16: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/16.jpg)
Comparingtwosystems
16
Mach3.0의 instruction이더비싸다
![Page 17: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/17.jpg)
Relativesystemoverheads
17
Mach3.0이느린
이유는
IPC때문만이아니다.
![Page 18: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/18.jpg)
7assertions
18
![Page 19: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/19.jpg)
1.Systemanduserlocality
• System의 locality는user보다낮을것이다?
• Lowlocality→Highcachemiss
19
![Page 20: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/20.jpg)
1.Systemanduserlocality
20
![Page 21: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/21.jpg)
2.Systemdependencyoncaches
• Instructioncache에서시간을더많이보낼것이다.
• MCPIcontribution?
21
특히Mach3.0에서더심하다.
System activity증가
![Page 22: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/22.jpg)
3.Competitionbetweentheuserandsystem• User와 system간
cache경쟁?
• Cache를따로
사용한다면?
22
큰성능차이가없다.
![Page 23: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/23.jpg)
4.Systemself-interference
• 동시에 cache에있어야하는instruction끼리경쟁?
• Cache associativity를올리면성능이좋아진다.
23
![Page 24: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/24.jpg)
5.Blockoperations
• Systemblockmemoryoperation에서
많은시간이소요된다?
• 전체MCPI중 큰비중을
차지할것이다.
24
![Page 25: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/25.jpg)
6.Streamingwrites
• Writebuffer는 systemcode를상대로성능이
안좋을것이다
• Systeminstruction을
실행시킬때
Writebufferstall이
빈번할것이다.
25
![Page 26: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/26.jpg)
7.Pagemappingstrategy
• Virtualpagemappingstrategy가
성능에미치는영향이클것이다.
•이전실험을 randomstrategy로바꾸면
성능차이가날것이다.
26
![Page 27: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/27.jpg)
MCPIcomparison(1)
27
Deterministic
Random
![Page 28: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/28.jpg)
MCPIcomparison(2)
28
Deterministic
Random
• Itcausessignificanteffect
• Inmostcase,randomisbetter
![Page 29: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/29.jpg)
Conclusion
• Tracing방법을이용해 systemoverhead가
어디서생기는지
파악할수있다.
• IPC의 overhead는 생각보다비중이적었다.
• Assertion7개중 6개가실제로성립한다는것을
확인할수있었다.
29
![Page 30: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/30.jpg)
MagazinesandVmem:ExtendingtheSlabAllocatorto
ManyCPUsandArbitraryResources
JeffBonwick,JonathanAdamsUSENIXAnnualTechnicalConference,GeneralTrack.01’
![Page 31: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/31.jpg)
Contents
• Introduction• SlabAllocator• Magazine• Vmem• Conclusion• Critic
31
![Page 32: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/32.jpg)
Introduction
• Slaballocatorhascontinuedtoevolve(94’~)• Per-CPUmemoryallocation• Moregeneralresourceallocation• Availableasauser-level library
32
![Page 33: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/33.jpg)
SlabAllocator
• 94’SunMicrosystemsSolarisimplemented
33
Slab : One or more pages of virtuallycontiguous memory
Object :Prepared spacefor frequently objects(ex.structure)
Maintainrunoutobjectsonfreelist ->Reduceallocationsandfreesinstructions
![Page 34: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/34.jpg)
34
Multiprocessor
![Page 35: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/35.jpg)
Magazine
• Background– per-CPUmemoryallocation• Slaballocatorneedslocktoprotectcache’sslablist• Needmultiprocessorscalability
35
obj obj obj obj obj obj obj obj obj objSlab
Mobjects
Magazine Magazine
![Page 36: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/36.jpg)
36
Magazine
Magazinefull+freeorMagazineempty+allocate
allocate
allocatefree
TradeinDepot(needlock)
Topreventfrequenttrade,thereispreviousmagazine
per-CPUcache
![Page 37: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/37.jpg)
Magazine(cont.)
• MagazineSize(M)• ObserveCPUlayer’smissrateaslowasbyincreasingM(Initialvalue)• Observethecontentionrateonthedepotlock(Incrementacontentioncount)
• Ifcontentionrateexceedsfixedthreshold,increasethemagazinesize
• DepotSize• Ifdepot’sfullmagazinelistvariesbetween37~47overagivenperiod,thenworkingsetis10magazines(Remainderareeligibleforreclaiming)
37
![Page 38: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/38.jpg)
MagazinePerformance
• Scalability• 333MHz16-CPUStarfire
• System-LevelBenchmark• SPECweb99• TPC-C• Kenbus
38
![Page 39: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/39.jpg)
Vmem
• Background– moregeneralresourceallocation• AlmostallversionsofUnixhaveresourcemapallocatorcalledrmalloc()• Linear-time algorithm
• Maintainalistoffreesegments• Coalescingsegmentstoreducefragments• Useinsertionsorttoreturnasegmenttothefreesegmentlist->O(n)
• Objectives• Constant-time performance->O(1)• Linearscalability• Lowfragmentation
39
![Page 40: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/40.jpg)
Vmem Structure
40
virtualmemory
heap
vmem_create(“heap”…)
kmem_va
vmem_create(“kmem_va”…)
kmem_default free allocated free allocated free
vmem_create(“kmem_default”…)
*
size
*
size
*
size
segmentlist
boundarytag
2^0 2^1 2^2 2^3 2^4
hashlist
freelist
![Page 41: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/41.jpg)
41
virtualmemory
heap
vmem_create(“heap”…)
kmem_va
vmem_create(“kmem_va”…)
kmem_default free allocated free allocated free
vmem_create(“kmem_default”…)
*
size
*
size
*
size
segmentlist
boundarytag
2^0 2^1 2^2 2^3 2^4
hashlist
freelist
![Page 42: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/42.jpg)
42
![Page 43: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/43.jpg)
Vmem Performance
• ConstantTime• Hash&Freelist로 allocated혹은 freesegment를 빠르게찾아진행할수있다.->O(1)
• Regardlessofarenafragmentation
• System-LevelBenchmark• LADDIS• WebService• I/OBandwidth
43
![Page 44: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/44.jpg)
User-LevelMemoryAllocation
44
mtmalloc :Selectingafreelist wassimplyround-robin
mtmalloc (fixed):Selectaper-CPUfreelist bythreadIDhashingasin
libumem
![Page 45: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/45.jpg)
Summary
• Magazine• Providesefficientobjectcachingwithverylowlatencyandlinearscaling
• Vmem• Guaranteeconstant-timeperformanceregardlessofallocationsizeorarenafragmentation
45
![Page 46: The Impact of Operating System Structure on Memory System …csl.skku.edu/uploads/ECE5658S16/pr9.pdf · 2016-05-01 · The Impact of Operating System Structure on Memory System Performance](https://reader033.fdocuments.in/reader033/viewer/2022041523/5e2fe8b3451ba25e02705fc5/html5/thumbnails/46.jpg)
Critic
46