Calvin: Fast Distributed Transactions for Partitioned Database Systems
The Calvin paper appeared in Sigmod 2012. I had read this paper before, and seen it covered in a reading group, but I never got to write a ...| muratbuffalo.blogspot.com
The Calvin paper appeared in Sigmod 2012. I had read this paper before, and seen it covered in a reading group, but I never got to write a ...| muratbuffalo.blogspot.com
This recent paper from the Berkeley Sky Computing Lab has been making waves in systems community. Of course, Aleksey and I did our live blin...| muratbuffalo.blogspot.com
This week, Aleksey and I met not to dissect a research paper, but to chat about "the process of PhD". I had recently wrote a post titled "The Invisible Curriculum of Research", where I framed research as an iceberg, with the small visible parts (papers, conferences) resting on the hidden 5 Cs:| Metadata
This paper (to appear at SOSP'25) is one of the latest efforts exploring the dream of a one-round commit for geo-replicated databases. TAPIR tried to fuse concurrency control and consensus into one layer. Tempo and Detock went further using dependency graphs. | Metadata
Courses, textbooks, and papers provide the formal curriculum of research. But there is also an invisible curriculum. Unwritten rules and skills separate the best researchers from the rest.| Metadata
This is my long-overdue trip report from last summer: July 10–11, 2024. We toured Ivy League campuses to help our rising senior son weigh his options, with our two daughters (our kids are four years apart each) tagging along for an early preview. Day one was Yale and Brown, followed by a night in New Jersey. Day two took us to Princeton and UPenn, then the long drive back to Buffalo. Of course we drove, that's howwe roll.| Metadata
This Berkeley systems group paper opens with the thesis that LLM agents will soon dominate data system workloads. These agents, acting on behalf of users, do not query like human analysts or even like the applications written by them. Instead, the LLM agents bombard databases with a storm of exploratory requests: schema inspections, partial aggregates, speculative joins, rollback-heavy what-if updates. The authors calls this behavior agentic speculation.| Metadata
This short VLDB'25 paper surveys disaggregation for cloud databases. It has several insightful points, and I found it worth summarizing. | Metadata
This year was a bastard. Not from work. God, no, I find work relaxing. Reading papers, inventing algorithms, ripping apart distributed systems with TLA+ models -- that's how I have fun. I can do that all day with a grin on my face. But the minute I need to do adulting (like simply calling the cable company and ask why keep increasing our bill when I'm not looking), I will stress and procrastinate. And this year, I had a lot of adulting to do to put our house on market, and plan a move to Cali...| Metadata
Small Gods (1992)| Metadata
People want data fast. They also want it consistent. Those two wants pull in opposite directions. This VLDB'25 paper does another take on this conundrum. Rather than assuming a symmetric network environment where all replicas face similar latencies, the paper emphasizes that in practice, some replicas are closer to the leader, where others are stranded halfway across the globe. By embracing this asymmetry, the authors propose two new algorithms: Pairwise-Leader (PL) and Pairwise-All (PA). Bot...| Metadata
This paper (to appear in VLDB'25) proposes a consensus algorithm called "Cabinet", which dynamically adjusts node weights based on responsiveness.| Metadata
This Google paper (to appear in VLDB'25) is about not blowing up your production system. That is harder than it sounds, especially with stateful applications with memories. When rolling out new versions of stateful applications, the "shared, persistent, mutable" data means bugs can easily propagate across versions. Modern rollout tricks (canaries, blue/green deployments) don't save you from this. Subtle cross-version issues often slip through pre-production testing and surface in production, ...| Metadata
This paper (VLDB'2024) looks at boosting transaction throughput through better scheduling. The idea is to explore the schedule-space more systematically and pick execution orders that reduce conflicts.| Metadata
The paper (arXiv 2020, also AI review 2023) opens up with discussing recent high-profile AI debates: the Montréal AI Debate and the AAAI 2020 fireside chat with Kahneman, Hinton, LeCun, and Bengio. A consensus seems to be emerging: for AI to be robust and trustworthy, it must combine learning with reasoning. Kahneman's "System 1 vs. System 2" dual framing of cognition maps well to deep learning and symbolic reasoning. And AI needs both.| Metadata
The paper (2023) argues for integrating two historically divergent traditions in artificial intelligence (neural networks and symbolic reasoning) into a unified paradigm called Neurosymbolic AI. It argues that the path to capable, explainable, and trustworthy artificial intelligence lies in marrying perception-driven neural systems with structure-aware symbolic models. | Metadata
This paper from HotStorage'25 presents OrcaCache, a design proposal for a coordinated caching framework tailored to disaggregated storage systems. In a disaggregated architecture, compute and storage resources are physically separated and connected via high-speed networks. These became increasingly common in modern data centers as they enable flexible resource scaling and improved fault isolation. (Follow the money as they say!) But accessing remote storage introduces serious latency and effi...| Metadata
This paper from SIGMOD 2016 proposes a transaction healing approach to improve the scalability of Optimistic Concurrency Control (OCC) in main-memory OLTP systems running on multicore architectures. Instead of discarding the entire execution when validation fails, the system repairs only the inconsistent operations to improve throughput in high-contention scenarios.| Metadata
This paper (PODC'2016) presents a clean and declarative treatment of Snapshot Isolation (SI) using dependency graphs. It builds on the foundation laid by prior work, including the SSI paper we reviewed recently, which had already identified that SI permits cycles with two adjacent anti-dependency (RW) edges, the so-called inConflict and outConflict edges. While the SSI work focused on algorithmic results and implementation, this paper focuses more on the theory (this is PODC after all) of def...| Metadata
I know I should call this recent listens, but I am stuck with the series name. So here it goes. These are some recent "reads" this month.| Metadata
Aleksey and I sat down to read this paper on Monday night. This was an experiment which aimed to share how experts read papers in real time. We haven't read this paper before to keep things raw. As it is with research, we ended up arguing with the paper (and between each other) back and forth. It was messy, and it was also awesome. We had a lot of fun. Check our discussion video below (please listen at 1.5x, I sound less horrible at that speed, ah also this thing is 2 hours long). The paper I...| Metadata
This EuroSys '23 paper reads like an SOSP best paper. Maybe it helped that EuroSys 2023 was in Rome. Academic conferences are more enjoyable when the venue doubles as a vacation.| Metadata
This paper (SIGMOD '08) proposes a lightweight runtime technique to make Snapshot Isolation (SI) serializable without falling back to locking. The key idea behind Serializable SI (SSI) is to detect potentially dangerous (write-skew) executions at runtime and abort one of the transactions to guarantee serializability (SER).| Metadata
ATC and OSDI ran in parallel. As is tradition, OSDI was single-track; ATC had two parallel tracks. The schedules and papers are online as linked above.| Metadata
This week I was in Boston for ATC/OSDI’25. Downtown Boston is a unique place where two/three-hundred-year-old homes and cobblestone streets are mixed with sleek buildings and biotech towers. The people here look wicked smart and ambitious (although lacking the optimism/cheer of Bay area people). It’s a sharp contrast from Buffalo, where the ambition is more about not standing out.| Metadata
Chapter 7 of the Concurrency Control and Recovery in Database Systems book by Bernstein and Hadzilacos (1987) tackles the distributed commit problem: ensuring atomic commit across a set of distributed sites that may fail independently.| Metadata
On distributed systems broadly defined and other curiosities. The opinions on this site are my own.| muratbuffalo.blogspot.com
The specification for consensus is as follows. The first two are safety properties, the last one a liveness property. Agreement : No two n...| muratbuffalo.blogspot.com
Chapter 7 of the Concurrency Control and Recovery in Database Systems book by Bernstein and Hadzilacos (1987) tackles the distributed commi...| muratbuffalo.blogspot.com
This paper is from IBM, 1992. This is a foundational paper in databases area. ARIES achieves long-running transaction recovery in a perform...| muratbuffalo.blogspot.com
So it goes: your system is purring like a tiger, devouring requests, until, without warning, it slumps into existential dread. Not a crash. ...| muratbuffalo.blogspot.com
This paper presents a new way to reason about transaction-isolation based on application-observable states, in lieu of prior history-based ...| muratbuffalo.blogspot.com
Chapter 5 of Concurrency Control and Recovery in Database Systems (1987) introduces multiversion concurrency control (MVCC), a fundamental ...| muratbuffalo.blogspot.com
Chapter 4 of the Concurrency Control and Recovery in Database Systems book (1987) opens with a sentence that doesn't quite pass the grammar...| muratbuffalo.blogspot.com
Chapter 3 presents two-phase locking (2PL). Remember I told you in Chapter 2: Serializability Theory that the discussion is very scheduler-...| muratbuffalo.blogspot.com
Joint work with Will Schultz . A transaction groups multiple operations into an all-or-nothing logical-box to reduce the surface area expose...| muratbuffalo.blogspot.com
I'm catching up on Phil Eaton's book club and just finished the preface and Chapter 1 of Concurrency Control and Recovery in Database Syste...| muratbuffalo.blogspot.com
This paper (to appear in VLDB'25) proposes a consensus algorithm called "Cabinet", which dynamically adjusts node weights based on responsi...| muratbuffalo.blogspot.com
This paper from SIGMOD 2016 proposes a transaction healing approach to improve the scalability of Optimistic Concurrency Control (OCC) in m...| muratbuffalo.blogspot.com
Aleksey and I sat down to read this paper on Monday night. This was an experiment which aimed to share how experts read papers in real tim...| muratbuffalo.blogspot.com
This EuroSys '23 paper reads like an SOSP best paper. Maybe it helped that EuroSys 2023 was in Rome. Academic conferences are more enjoyabl...| muratbuffalo.blogspot.com
With Chapter 6, the Concurrency Control and Recovery in Database Systems book shifts focus from concurrency control to the recovery! This c...| muratbuffalo.blogspot.com
Chapter 2 of Concurrency Control and Recovery in Database Systems (1987) by Bernstein, Hadzilacos, and Goodman is a foundational treatment ...| muratbuffalo.blogspot.com
I attended the TLA+ Community Event at Hamilton, Ontario on Sunday. Several talks pushed the boundaries of formal methods in the real world...| muratbuffalo.blogspot.com
This EuroSys 2025 paper wrestles with the messy interface between formal specification and implementation reality in distributed systems. T...| muratbuffalo.blogspot.com
This paper (2021) dives deeper in the Parallel Raft protocol introduced with PolarFS. PolarFS (VLDB'18) is a distributed file system with ...| muratbuffalo.blogspot.com
I have been reviewing papers for USENIX ATC and handling work stuff at MongoDB Research. I cannot blog about either yet. So, instead of a pa...| muratbuffalo.blogspot.com
Distributed systems are characterized by nodes executing concurrently with no shared state and no common clock. Coordination between nodes a...| muratbuffalo.blogspot.com
This master's thesis at Lund University Sweden explores how CockroachDB 's transactional performance can be improved by using tightly synch...| muratbuffalo.blogspot.com
Incremental computation represents a transformative (!) approach to data processing. Instead of recomputing everything when your input chang...| muratbuffalo.blogspot.com
I have been teaching a TLA+ miniseries inside AWS. I just finished the 10th week, with a one hour seminar each week. I wanted to pen down my...| muratbuffalo.blogspot.com
