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Neural Packet Classification [article]

Eric Liang, Hang Zhu, Xin Jin, Ion Stoica
2019 arXiv   pre-print
Packet classification is a fundamental problem in computer networking. This problem exposes a hard tradeoff between the computation and state complexity, which makes it particularly challenging. To navigate this tradeoff, existing solutions rely on complex hand-tuned heuristics, which are brittle and hard to optimize. In this paper, we propose a deep reinforcement learning (RL) approach to solve the packet classification problem. There are several characteristics that make this problem a good
more » ... t for Deep RL. First, many of the existing solutions are iteratively building a decision tree by splitting nodes in the tree. Second, the effects of these actions (e.g., splitting nodes) can only be evaluated once we are done with building the tree. These two characteristics are naturally captured by the ability of RL to take actions that have sparse and delayed rewards. Third, it is computationally efficient to generate data traces and evaluate decision trees, which alleviate the notoriously high sample complexity problem of Deep RL algorithms. Our solution, NeuroCuts, uses succinct representations to encode state and action space, and efficiently explore candidate decision trees to optimize for a global objective. It produces compact decision trees optimized for a specific set of rules and a given performance metric, such as classification time, memory footprint, or a combination of the two. Evaluation on ClassBench shows that NeuroCuts outperforms existing hand-crafted algorithms in classification time by 18% at the median, and reduces both time and memory footprint by up to 3x.
arXiv:1902.10319v1 fatcat:tmnty3hmgfhazb6ojofastihx4

An Econophysics Model for the Stock-Markets' Analysis and Diagnosis [article]

Ion Spanulescu, Ion Popescu, Victor Stoica, Anca Gheorghiu, Victor Velter
2011 arXiv   pre-print
In this paper we present an econophysic model for the description of shares transactions in a capital market. For introducing the fundamentals of this model we used an analogy between the electrical field produced by a system of charges and the overall of economic and financial information of the shares transactions from the stock-markets. An energetic approach of the rate variation for the shares traded on the financial markets was proposed and studied.
arXiv:1101.4680v1 fatcat:3qjwdvnfrbashek35shrnejjvq

Selected Aspects of Flow Phenomena in Heavy Ion Collisions

Mihai Petrovici, Amalia Pop, Livius Trache, Sabin Stoica
2008 AIP Conference Proceedings  
A review of the main results of detailed flow analysis in highly central and semicentral heavy ion collisions at SIS energies is presented in the first part of this paper.  ...  Pop Collective phenomena in heavy ion collisions  ...  One of these is the dynamical evolution of the transient piece of matter produced in heavy ion collisions.  ... 
doi:10.1063/1.2870482 fatcat:isyyllylizb3pi6xoge6cy2bb4


Lakshminarayanan Subramanian, Ion Stoica, Hari Balakrishnan, Randy H. Katz
2003 Computer communication review  
This paper proposes OverQoS, an architecture for providing Internet QoS using overlay networks. OverQoS empowers third-party providers to offer enhanced network services to their customers using the notion of a controlled loss virtual link (CLVL). The CLVL abstraction bounds the loss-rate experienced by the overlay traffic; OverQoS uses it to provide differential rate allocations, statistical bandwidth and loss assurances, and enables explicit-rate congestion control algorithms.
doi:10.1145/774763.774764 fatcat:un3oz6hmqveyzm42v2k7lahnsu


Matthew Caesar, Tyson Condie, Jayanthkumar Kannan, Karthik Lakshminarayanan, Ion Stoica
2006 Computer communication review  
It is accepted wisdom that the current Internet architecture conflates network locations and host identities, but there is no agreement on how a future architecture should distinguish the two. One could sidestep this quandary by routing directly on host identities themselves, and eliminating the need for network-layer protocols to include any mention of network location. The key to achieving this is the ability to route on flat labels. In this paper we take an initial stab at this challenge,
more » ... posing and analyzing our ROFL routing algorithm. While its scaling and efficiency properties are far from ideal, our results suggest that the idea of routing on flat labels cannot be immediately dismissed.
doi:10.1145/1151659.1159955 fatcat:27cfa676cnhzjf6manf2hqjoem

9 Conclusions and Future Work [chapter]

Ion Stoica
2004 Lecture Notes in Computer Science  
doi:10.1007/978-3-540-24706-7_9 fatcat:bujuwo4gfjasbge3zy7zc62lwy

Heavy Ion Collisions and New Forms of Matter

Larry McLerran, Arttu Rajantie, Carlo Contaldi, Paul Dauncey, Horace Stoica
2007 AIP Conference Proceedings  
They all might be studied in ultra-relativistic heavy ion collisions, nd the Color Glass Condensate might also be probed in electron-hadron collisions.  ...  FIGURE 1 . 1 A schematic picture of the evolution of matter produced in the heavy ion collisions.  ...  It is a theoretical discovery but its direct applicability to heavy ion collisions remains to be shown.  ... 
doi:10.1063/1.2823746 fatcat:vshvhzwxnnfv7lj6zglzwn6ife


Ion Stoica, Robert Morris, David Karger, M. Frans Kaashoek, Hari Balakrishnan
2001 Computer communication review  
A fundamental problem that confronts peer-to-peer applications is to efficiently locate the node that stores a particular data item. This paper presents Chord, a distributed lookup protocol that addresses this problem. Chord provides support for just one operation: given a key, it maps the key onto a node. Data location can be easily implemented on top of Chord by associating a key with each data item, and storing the key/data item pair at the node to which the key maps. Chord adapts
more » ... as nodes join and leave the system, and can answer queries even if the system is continuously changing. Results from theoretical analysis, simulations, and experiments show that Chord is scalable, with communication cost and the state maintained by each node scaling logarithmically with the number of Chord nodes.
doi:10.1145/964723.383071 fatcat:fijrsdfs7rardows5nlwg2ikja

Declarative routing

Boon Thau Loo, Joseph M. Hellerstein, Ion Stoica, Raghu Ramakrishnan
2005 Computer communication review  
The Internet's core routing infrastructure, while arguably robust and efficient, has proven to be difficult to evolve to accommodate the needs of new applications. Prior research on this problem has included new hard-coded routing protocols on the one hand, and fully extensible Active Networks on the other. In this paper, we explore a new point in this design space that aims to strike a better balance between the extensibility and robustness of a routing infrastructure. The basic idea of our
more » ... ution, which we call declarative routing, is to express routing protocols using a database query language. We show that our query language is a natural fit for routing, and can express a variety of well-known routing protocols in a compact and clean fashion. We discuss the security of our proposal in terms of its computational expressive power and language design. Via simulation, and deployment on Plan-etLab, we demonstrate that our system imposes no fundamental limits relative to traditional protocols, is amenable to query optimizations, and can sustain long-lived routes under network churn and congestion.
doi:10.1145/1090191.1080126 fatcat:vhttbhrngbf4pcrxydvh4gbj5i

Core-stateless fair queueing

Ion Stoica, Scott Shenker, Hui Zhang
1998 Computer communication review  
Our algorithm is built around several estimat,ion procedures, and thus is inherently inexact.  ...  However, our interest is not in perfect,ion, but only in obtaining reasonable approximations to the fair bandwidth allocations.  ... 
doi:10.1145/285243.285273 fatcat:jgaf5uxe4bcanlo2ux2ysy4jh4

numpywren: serverless linear algebra [article]

Vaishaal Shankar, Karl Krauth, Qifan Pu, Eric Jonas, Shivaram Venkataraman, Ion Stoica, Benjamin Recht, Jonathan Ragan-Kelley
2018 arXiv   pre-print
Linear algebra operations are widely used in scientific computing and machine learning applications. However, it is challenging for scientists and data analysts to run linear algebra at scales beyond a single machine. Traditional approaches either require access to supercomputing clusters, or impose configuration and cluster management challenges. In this paper we show how the disaggregation of storage and compute resources in so-called "serverless" environments, combined with compute-intensive
more » ... workload characteristics, can be exploited to achieve elastic scalability and ease of management. We present numpywren, a system for linear algebra built on a serverless architecture. We also introduce LAmbdaPACK, a domain-specific language designed to implement highly parallel linear algebra algorithms in a serverless setting. We show that, for certain linear algebra algorithms such as matrix multiply, singular value decomposition, and Cholesky decomposition, numpywren's performance (completion time) is within 33% of ScaLAPACK, and its compute efficiency (total CPU-hours) is up to 240% better due to elasticity, while providing an easier to use interface and better fault tolerance. At the same time, we show that the inability of serverless runtimes to exploit locality across the cores in a machine fundamentally limits their network efficiency, which limits performance on other algorithms such as QR factorization. This highlights how cloud providers could better support these types of computations through small changes in their infrastructure.
arXiv:1810.09679v1 fatcat:lxv65s42rzd6vomkg2pff2akhm

Internet indirection infrastructure

Ion Stoica, Daniel Adkins, Shelley Zhuang, Scott Shenker, Sonesh Surana
2002 Computer communication review  
Stoica, D. Adkins, S. Zhuang, and S.  ... 
doi:10.1145/964725.633033 fatcat:qank3z53nrgrln7ceja6cthnne

Variable Skipping for Autoregressive Range Density Estimation [article]

Eric Liang, Zongheng Yang, Ion Stoica, Pieter Abbeel, Yan Duan, Xi Chen
2020 arXiv   pre-print
Deep autoregressive models compute point likelihood estimates of individual data points. However, many applications (i.e., database cardinality estimation) require estimating range densities, a capability that is under-explored by current neural density estimation literature. In these applications, fast and accurate range density estimates over high-dimensional data directly impact user-perceived performance. In this paper, we explore a technique, variable skipping, for accelerating range
more » ... y estimation over deep autoregressive models. This technique exploits the sparse structure of range density queries to avoid sampling unnecessary variables during approximate inference. We show that variable skipping provides 10-100× efficiency improvements when targeting challenging high-quantile error metrics, enables complex applications such as text pattern matching, and can be realized via a simple data augmentation procedure without changing the usual maximum likelihood objective.
arXiv:2007.05572v1 fatcat:6eksq3er4fhj3hr7i4vexn7hai

Probabilistically Bounded Staleness for Practical Partial Quorums [article]

Peter Bailis, Shivaram Venkataraman, Michael J. Franklin, Joseph M. Hellerstein, Ion Stoica
2012 arXiv   pre-print
Data store replication results in a fundamental trade-off between operation latency and data consistency. In this paper, we examine this trade-off in the context of quorum-replicated data stores. Under partial, or non-strict quorum replication, a data store waits for responses from a subset of replicas before answering a query, without guaranteeing that read and write replica sets intersect. As deployed in practice, these configurations provide only basic eventual consistency guarantees, with
more » ... limit to the recency of data returned. However, anecdotally, partial quorums are often "good enough" for practitioners given their latency benefits. In this work, we explain why partial quorums are regularly acceptable in practice, analyzing both the staleness of data they return and the latency benefits they offer. We introduce Probabilistically Bounded Staleness (PBS) consistency, which provides expected bounds on staleness with respect to both versions and wall clock time. We derive a closed-form solution for versioned staleness as well as model real-time staleness for representative Dynamo-style systems under internet-scale production workloads. Using PBS, we measure the latency-consistency trade-off for partial quorum systems. We quantitatively demonstrate how eventually consistent systems frequently return consistent data within tens of milliseconds while offering significant latency benefits.
arXiv:1204.6082v1 fatcat:77y7biwjs5fqrgp67sdwsdkbw4

Nothingness: A philosophical reconsideration to the meaning of negation and reality

Ioan Dura, Ion Ene, Andrei Hera, Ion Pana, Mihai Stoica
2022 XLinguae  
Philosophical constructions have always revolved around fundamental existential issues. In an attempt to interpret the meaning of these issues, complex concepts capable of synthesising cardinal truths have been developed. This study intends to explore, on the one hand, the patterns of Mādhyamika philosophy of understanding negation as a logical-rational operation that denotes reality, and on the other hand, attempts to decipher the meaning of the term śūnya ("nothingness"), misunderstood in the West as nihilism.
doi:10.18355/xl.2022.15.01.03 fatcat:tsh76c6v6jc6hgkja4swqpurcu
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