企业级SSD缓存设计的思考

1、技术创新，变革未来企业级 SSD 缓存设计的思考OutlineW h a t isS S DC a c h e ?C a c h e fu n c t io n I n tr o d u c t io nP e r fo r m a n c e tu n in gw i th C a c h eC a c h e d e s ig n c h a l le n g eC a c h e w i th m a c h in e le a r n in gC a c h e S W /H Wc o - d e s ig nW h a tisS S DC a c h e ?SSD&PMDRAMPMP

2、MSSDPM DriverMemory BusApplicationsSSD DriverPCI BusWrite DominantPM Aware AppsIn-MemoryTraditional AppsRead DominantByte(Cache Line)IOBlock IOByte (Cache Line)IOMMULoad/Store Mem Mapped Unit Byte AddressableDDABlock IO Direct Data Raw AccessPM Aware File SystemFile SystemRead/Write Block IODCPMMXL

3、Flash NVMe SSDNVDIMM-N3D NAND NVMe SSDOptaneNVMe SSDTe s t S a m p le P o o l :Optane NVMe SSD, XL Flash SSD, 3D NAND NVDIMM-N, Optane DCPMMXL Flash NVMe SSD- DapuStor3D X Point OptaneSSD - Intel3D NAND NVMe SSD- Huawe iOptane 3D X Point PM Intel DCPMMNVDIMM-NPM SMART ModularSSDBasicArchSSD Controll

4、er/ DRAM/ Flash / CapacitorDRAM:Cache，l2p table ，Data structure/ Code10 20MB1000: 1, 1000:2110 MBMemory Controller/ 3D Xpoin tNo DRAM, no capacitorCacheModuleCacheModuleC a c h efu n c t io nI n t r o d u c t io nCacheFunction s/Performance1.W r i tela te n c yS S DS p e c4k w r i te1 0u sla te n c

5、y, tP r o gism u c hh ig h e r2 . Re a dla te n c yS S Ds p e cis4k s e qu e n t ia l re a dla te n c y is1 0 u s , tR ism u c hh ig h e r3.Ba c kp r e s s u r efo rra n d o mW r i tec o n s is te n c y4.51 2Bytep e r fo r m a n c eCacheFunction s/backPressu reCacheFunction s/FTL1.C o n ve r tI Oto4

6、kba s e2 . Er r o rh a n d l in gP r o g r a mfa i l d a taw i l l bew r i tte na g a inH o tW r i ted a taMys ql h o t d a taw i l l bew i th in1 0 0 MB ra n g eH o tre a dd a taAvoidth ere a dd i s tr u bI OC o n f l ic tC o p ysof d a ta4K + 1 2 8 c o n ve r t to8K ove r la pP e r fo r m a n c et

7、u n in gw i thc a c h e d e s ig nHaishe nXLProductWriteIOPath/manualWriteIOPath/optimizeOracle /LogDriveXFS BeforeAfterSSDTPM(1 user)TPM(30 users)TPM(64 users)Haishen XL Enterprise SSD5594014795631944352Intel Optane SSD63238157019021850792500000200000015000001000000500000064 usersOracle1 user30 use

8、rsHaishe n XL Enterprise SSDIntel Optane SSDSSD1 user30 users64 usersHaishen XL Enterprise SSD6732117618002329788Intel Optane SSD68987173607523553482500000200000015000001000000500000064 usersOracle (after optimization )1 user30 usersHaishe n XL Enterprise SSDIntel Optane SSDOracle /LogDriveext4SSDTP

9、M(1 user)TPM(30 users)TPM(64 users)Haishen XL Enterprise SSD6289415477242120076Intel Optane SSD5926015579572158507SSD1 user30 users64 usersHaishen XL Enterprise SSD7175217695732146791Intel Optane SSD66324169047721545412500000200000015000001000000500000064 usersOracle1 user30 usersHaishe n XL Enterpr

10、ise SSDIntel Optane SSD2500000200000015000001000000500000064 usersOracle (after optimization )1 user30 usersHaishe n XL Enterprise SSDIntel Optane SSDXL-Flashw/datadriveC a c h eD e s ig nC h a l le n g eC a c h eD e s ig nC h a l le n g e1. S o f tw a r ela te n c y w i l l be bottle n e c kGe n3 -

11、 Ge n4 - Ge n5C o r efr e qu e n c y, 650 Mh z - 1 Gh z - 1 .6Gh z?2 . C a c h eh i t ra tew i thre a l w o r klo a dC a c h es izevsC a p a c i to rlin e a ru pMor ed ie sa n din te r le a ve , 1 6 c h a n n e lsS S DD RAM c h a n g eFre qu e n c y, 2 40 0 Mh z, 2 666Mh z Mor era c ks , RD I MM, LR

12、D I MM Re l ia bilityC a c h ew i thMa c h in ele a r n in gInput layer 4 cells:I/O addressI/O lengthRW ratioRW intervalOutput layer 1 cell:I/O intensityHidden layer 128 cellsLSTM layer 128 cellsHistory windowSlidingwindowPrediction windowHistory time slotI/O features1. AddressLengthRW ratioRW intervalCurrent I/OFuture time slotI/O intensive within 10ms in future？Input&OutputoftheModelIOPredictionResultsThe prediction result of storage I/O trace s (configu ration: history =1K, predict period=1ms)FurtherworkRandom