Contact Information
Engineering 2, room 213
University of California, Santa Cruz
ude.cscu@ztilh


Welcome to my webpage! I am an Associate Professor in the Computer Science & Engineering (CSE) Department of the Baskin School of Engineering at the University of California Santa Cruz and the Director of the Center for Research in Storage Systems (CRSS). I am also a member of UCSC's Hardware Systems Collective (HSC). My general research interests are in computer architecture and systems, whereas my current work focusses on improving the hardware-software interface of general purpose processors for emerging data center workloads. I design new microarchitectural mechanisms for the frontend (branch predictor, BTB, instruction cache), mid end (scheduler), and back end (prefetching, memory hierarchy), leveraging compiler and profile-guided optimization techniques. Before joining UCSC, I was a researcher at Google and a Postdoc at Stanford University where I worked with Christos Kozyrakis and David Cheriton. I received my PhD from Mannheim University.

I have open PhD, MS, and Postdoc positions in the area of core microarchitecture. If you are interested, please get in contact with me and reference my name in your statement when applying at UCSC.

UPDATE: I am on sabbatical at MIT CSAIL and are currently not offering office hours. If you are in the Boston area, please reach out: ude.tim@ztilh

Curriculum Vitae



Full CV

Teaching

  • CSE120 - Computer Architecture: Fall'19, Winter'20, Fall'21, Winter'22, Fall'23
  • CSE121 - Embedded Systems: Fall'22
  • CSE125/CSE225 - Hardware Design with Verilog: Spring'19, Spring'20, Spring'21
  • CSE220 - Advanced Computer Architecture: Winter'21, Spring'23
  • CSE226 - Advanced Parallel Programming: Winter'19, Fall'20
  • CSE226 - Computer Systems and Assembly Language and Lab: Winter'24

Office Hours


On request. Please send me an email.

Students

Graduated Students

Support


I am grateful to NSF, Intel, Samsung, Google, and Facebook for supporting my research.

Publications

  • Surim Oh, Mingsheng Xu, Tanvir Ahmed Khan, Baris Kasikci, Heiner Litz
    UDP: Utility-Driven Fetch Directed Instruction Prefetching
    in the 51th International Symposium on Computer Architecture (ISCA), 2024
  • Yuxuan Zhang, Nathan Sobotka, Soyoon Park, Saba Jamilan, Tanvir Ahmed Khan, Baris Kasikci, Gilles Pokam, Heiner Litz, Joseph Devietti
    RPG^2: Robust Profile-Guided Runtime Prefetch Generation
    in the 29th International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS'29), 2024
    [PDF]
  • Yuanjiang Ni, Pankaj Mehra, Ethan Miller, Heiner Litz
    TMC: Near-Optimal Resource Allocation for Tiered-Memory Systems
    in Symposium on Cloud Computing (SoCC), 2023
    [PDF]
  • Lokesh N. Jaliminche, Chandranil (Nil) Chakraborttii, Changho Choi, Heiner Litz
    Enabling Multi-tenancy on SSDs with Accurate IO Interference Modeling
    in Symposium on Cloud Computing (SoCC), 2023
    [PDF]
  • Yuxuan Zhang, Tanvir Ahmed Khan, Gilles Pokam, Baris Kasikci, Heiner Litz, Joseph Devietti
    Online COde Layout OptimizationS via OCOLOS
    IEEE MICRO TOP PICK 2023
  • Yi Liu, Shouqian Shi, Minghao Xie, Heiner Litz, and Chen Qian
    SMASH: Flexible, Fast, and Resource-efficient Placement and Lookup of Distributed Storage
    in Measurement and Analysis of Computing Systems (SIGMETRICS), 2023
    [PDF]
  • Tanvir Ahmed Khan, Muhammed Ugur, Krishnendra Nathella, Dam Sunwoo, Heiner Litz, Daniel A. Jimenez, Baris Kasikci
    Whisper: Profile-Guided Branch Misprediction Elimination for Data Center Applications
    in the 55th Annual IEEE/ACM International Symposium on Microarchitecture (MICRO), 2022
    BEST PAPER [PDF]
  • Yuxuan Zhang, Tanvir Ahmed Khan, Gilles Pokam, Baris Kasikci, Heiner Litz, Joseph Devietti
    OCOLOS: Online COde Layout OptimizationS
    in the 55th Annual IEEE/ACM International Symposium on Microarchitecture (MICRO), 2022
    [PDF]
  • Shixin Song, Tanvir Ahmed Khan, Sara Mahdizadeh Shahri, Akshitha Sriraman, Niranjan K Soundararajan, Sreenivas Subramoney, Daniel A Jiménez, Heiner Litz, and Baris Kasikci
    Thermometer: Profile-Guided BTB Replacement for Data Center Applications.
    in the 49th International Symposium on Computer Architecture (ISCA), 2022
    [PDF]
  • Saba Jamilan, Tanvir A. Khan, Grant Ayers, Baris Kasikci, Heiner Litz
    APT-GET: Profile-Guided Timely Software Prefetching
    in the The European Conference on Computer Systems (EuroSys), 2022
    [PDF]
  • Heiner Litz, Grant Ayers, Parthasarathy Ranganathan
    CRISP: Critical Slice Prefetching
    in the 27th International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS'27), 2022
    [PDF] [VIDEO]
  • Devashish R Purandare, Peter Wilcox, Heiner Litz, Shel Finkelstein
    Append is Near: Log-based Data Management on ZNS SSDs
    The Conference on Innovative Data Systems Research (CIDR'22), 2022
    [PDF]
  • Tanvir Ahmed Khan, Nathan Brown, Akshitha Sriraman, Niranjan K Soundararajan, Rakesh Kumar, Joseph Devietti, Sreenivas Subramoney, Gilles A Pokam, Heiner Litz, Baris Kasikci
    Twig: Profile-Guided BTB Prefetching for Data Center Applications
    in the 54th Annual IEEE/ACM International Symposium on Microarchitecture (MICRO), 2021
    [PDF]
  • Niranjan K Soundararajan, Peter Braun, Tanvir Ahmed Khan, Baris Kasikci, Heiner Litz, Sreenivas Subramoney
    PDede: Partitioned, Deduplicated, Delta Branch Target Buffer
    in the 54th Annual IEEE/ACM International Symposium on Microarchitecture (MICRO), 2021
    [PDF]
  • Tanvir Ahmed Khan, Dexin Zhang, Akshitha Sriraman, Joseph Devietti, Gilles Pokam, Heiner Litz, Baris Kasikci
    Ripple: Profile-Guided Instruction Cache Replacement for Data Center Applications
    in the 48th International Symposium on Computer Architecture (ISCA), 2021
    [PDF]
  • Heiner Litz, Javier Gonzalez, Ana Klimovic, Christos Kozyrakis
    RAIL: Predictable, Low Tail Latency for NVMe Flash
    ACM Transactions on Storage (TOS), 2021
    [PDF]
  • Chandranil Chackraborttii, Heiner Litz
    Reducing Write Amplification in Flash by Death-time Prediction of Logical Block Addresses
    in the 14th International System and Storage Conference (SYSTOR), 2021
    [PDF]
  • Saeed Kargar, Heiner Litz, Faisal Nawab
    Predict and Write: Using K-Means Clustering to Extend the Lifetime of NVM Storage
    in the 37th IEEE International Conference on Data Engineering (ICDE), 2021
    [PDF]
  • Tanvir Ahmed Khan, Akshitha Sriraman, Joseph Devietti, Gilles Pokam, Heiner Litz, Baris Kasikci
    I-SPY: Context-Driven Conditional Instruction Prefetching with Coalescing
    in the 53nd Annual IEEE/ACM International Symposium on Microarchitecture (MICRO), 2020
    [PDF]
  • Chandranil Chakraborttii, Heiner Litz
    Improving the Accuracy, Adaptability, and Interpretability of SSD Failure Prediction Models
    in the ACM Symposium on Cloud Computing 2020 (SoCC), 2020
    [PDF]
  • Chandranil Chakraborttii, Heiner Litz
    Learning I/O Access patterns to Improve Prefetching in SSDs
    in the European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases (ECML-PKDD), 2020
    [PDF][CODE]
  • Nayana Prasad Nagendra, Grant Ayers, David I. August, Hyoun Kyu Cho, Svilen Kanev, Christos Kozyrakis, Trivikram Krishnamurthy, Heiner Litz, Tipp Moseley, Parthasarathy Ranganathan
    AsmDB: Understanding and Mitigating Front-end Stalls in Warehouse-Scale Computers
    IEEE MICRO TOP PICK 2019 [PDF]
  • Grant Ayers, Heiner Litz, Christos Kozyrakis, Parthasarathy Ranganathan
    Classifying Memory Access Patterns for Prefetching
    in the 25th International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS'25), 2020
    [PDF]
  • Yuanjiang Ni, Jishen Zhao, Heiner Litz, Daniel Bittman, Ethan L. Miller
    SSP: Eliminating Redundant Writes in Failure-Atomic NVRAMs via Shadow Sub-Paging
    in the 52nd Annual IEEE/ACM International Symposium on Microarchitecture (MICRO), 2019
    [PDF]
  • Grant Ayers, Nayana Prasad Nagendra, David I. August, Hyoun Kyu Cho, Svilen Kanev, Christos Kozyrakis, Trivikram Krishnamurthy, Heiner Litz, Tipp Moseley, Parthasarathy Ranganathan
    AsmDB: Understanding and Mitigating Front-end Stalls in Warehouse-Scale Computers
    in the 46th International Symposium on Computer Architecture (ISCA), 2019
    [PDF]
  • Milad Hashemi, Kevin Swersky, Jamie A. Smith, Grant Ayers, Heiner Litz, Jichuan Chang, Christos Kozyrakis, Parthasarathy Ranganathan
    Learning Memory Access Patterns
    in the 35th International Conference on Machine Learning (ICML), 2018
    [PDF]
  • Ana Klimovic, Heiner Litz, Christos Kozyrakis
    Selecta: Learning Heterogeneous Cloud Storage Configuration for Data Analytics
    in the 2018 USENIX Annual Technical Conference (USENIX'18), 2018
    [PDF]
  • Samuel Grossman, Heiner Litz, Christos Kozyrakis
    Making Pull-Based Graph Processing Performant
    in the 23rd ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming (PPoPP'23), 2018
    [PDF][CODE]
  • Ana Klimovic, Heiner Litz, Christos Kozyrakis
    ReFlex: Remote Flash == Local Flash
    in the 22nd International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS'22), 2017
    [PDF][CODE]
  • Heiner Litz, Benjamin Braun, David Cheriton
    EXCITE-VM: Extending the Virtual Memory System to Support Snapshot Isolation Transactions
    in the 25th International Confernce on Parallel Architectures and Compilation Techniques (PACT'25), 2016
    [PDF]
  • Heiner Litz, Ricardo J. Dias, David Cheriton
    Efficient Correction of Anomalies in Snapshot Isolation Transactions
    in ACM Transactions on Architecture and Code Optimization (TACO), 2015
    [PDF]
  • Heiner Litz, David Cheriton, Amin Firozshahian, Omid Azizi, J. Peter Stevenson
    SI-TM: Improving Transactional Memory Abort Rates through Snapshot Isolation
    in Proceedings of the 19th Internation Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS'19), March 2014
    [PDF]
  • Bo Wang, Heiner Litz, David Cheriton
    HICAMP Bitmap: Space-efficient Updatable Bitmap Index for In-memory Databases
    In 10th International Workshop on Data Management on New Hardware (DAMON'10), June 2014
    [PDF]
  • Michael Chan, Heiner Litz, David Cheriton
    Rethinking Network Stack Design with Memory Snapshots
    in Proceedings of the 14th Usenix Workshop on Hot Topics in Operating Systems (HotOS'14)
    [PDF]
  • Holger Fröning, Mondrian Nüssle, Heiner Litz, Christian Leber and Ulrich Brüning
    On Achieving High Message Rates
    in Proceedings of the 13th IEEE/ACM International Symposium on Cluster, Cloud and Grid Computing (CCGrid-2013), May 13-16, 2013, Delft, The Netherlands
    [PDF]
  • Heiner Litz, Christian Leber, Benjamin Geib
    DSL Programmable Engine for High Frequency Trading Acceleration
    in Proceedings of the 4th Workshop on High Performance Computational Finance (WHPCF-2011), co-located with SC11, November 13th, 2011, Seattle, USA
    [PDF]
  • Christian Leber, Benjamin Geib, Heiner Litz
    High Frequency Trading Acceleration using FPGAs
    in Proceedings of the 21rd International Conference on Field Programmable Logic and Applications (FPL'21), September 5-7, 2011, Chania, Greece
    [PDF]
  • Heiner Litz, Maximilian Thürmer, Ulrich Brüning
    TCCluster: A Cluster Architecture Utilizing the Processor Host Interface as a Network Interconnect
    in Proceedings of IEEE International Conference on Cluster Computing (CLUSTER), September 20-24, 2010, Heraklion, Greece
    [PDF]
  • Holger Fröning and Heiner Litz
    Efficient Hardware Support for the Partitioned Global Address Space
    in Proceedings of the 10th Workshop on Communication Architecture for Clusters (IPDPSW), co-located with the 24th International Parallel and Distributed Processing Symposium (IPDPS 2010), April 19, 2010, Atlanta, Georgia
    [PDF]
  • Heiner Litz, Holger Fröning, Maximilian Thürmer, Ulrich Brüning
    An FPGA based Verification Platform for HyperTransport 3.x
    in Proceedings of the 19th International Conference on Field Programmable Logic and Applications (FPL'19), August 31 - September 2, 2009, Prag, Czech Republic
    [PDF]
  • Heiner Litz, Holger Fröning, Ulrich Brüning
    A HyperTransport 3 Physical Layer Interface for FPGAs
    in Proceedings of the 5th International Workshop on Applied Reconfigurable Computing (ARC'6) , March 16 - 18, 2009, Karlsruhe, Germany
    [PDF]
    Best paper award!
  • Holger Fröning, Heiner Litz, Ulrich Brüning
    Efficient Virtualization of Network Interfaces
    in Proceedings of the 8th International Conference on Networks (ICN'8), March 1-6, 2009, Guadeloupe/France
    [PDF]
  • Benjamin Kalisch, Alexander Giese, Heiner Litz, Ulrich Brüning
    HyperTransport 3 Core: A Next Generation Host Interface with Extremely High Bandwidth
    in Proceedings of the 1st International Workshop on HyperTransport Research and Applications (WHTRA-2009), February 12th, 2009, Mannheim, Germany
    [PDF]
  • Heiner Litz, Holger Fröning, Mondrian Nüssle,  Ulrich Brüning
    VELO: A Novel Communication Engine for Ultra-low Latency Message Transfers
    In Proceedings of the 37th International Conference on Parallel Processing (ICPP-2008), Sep. 8 - 12, 2008, Portland, USA
    Best paper award!
    [PDF]
  • Mondrian Nüssle, Holger Fröning, Alexander Giese, Heiner Litz, David Slogsnat, Ulrich Brüning
    A Hypertransport based low-latency reconfigurable testbed for message-passing developments
    in Proceedings of the 2nd Workshop Kommunikation in Clusterrechnern und Clusterverbundsystemen (KiCC'07), TU Chemnitz, February 2007.
  • Holger Fröning, Mondrian Nüssle, David Slogsnat, Heiner Litz, Ulrich Brüning
    The HTX-Board: A Rapid Prototyping Station
    in Proceedings of the 3rd annual FPGAworld Conference (FPGA-2006), Nov. 16, 2006, Stockholm, Sweden.
  • Yun Ding, Heiner Litz
    Creating Multiplatform User Interfaces by Annotation and Adaptation'
    Proceedings of International Conference on Intelligent User Interfaces (IUI'11), Sydney, Australia, 29 January 2006 -- 1 February 2006
  • Yun Ding, Heiner Litz, Dennis Pfisterer
    A graphical single-authoring framework for building multi-platform user interfaces
    Proceedings of the Conference on Computer Aided Design of User Interfaces (CADUI), held with the International Conference on Intelligent User Interfaces (IUI'9), Funchal, Portugal, 14-16 January 2004
  • Yun Ding, Heiner Litz, Rainer Malaka and Dennis Pfisterer
    On Programming Information Agent Systems - An Integrated Hotel Reservation Service as Case Study
    Proceedings of the first German Conference on Multiagent System Technologies (MATES'03), 2003

Support


Our group's research is generously supported by -- NSF, Intel, Google, Samsung, Meta, Western Digital, Broadcom