{"title":"Model Agnostic Time Series Analysis via Matrix Estimation","authors":"Anish Agarwal, M. Amjad, D. Shah, Dennis Shen","doi":"10.1145/3309697.3331479","DOIUrl":"https://doi.org/10.1145/3309697.3331479","url":null,"abstract":"We propose an algorithm to impute and forecast a time series by transforming the observed time series into a matrix, utilizing matrix estimation to recover missing values and de-noise observed entries, and performing linear regression to make predictions. At the core of our analysis is a representation result, which states that for a large class of models, the transformed time series matrix is (approximately) low-rank. In effect, this generalizes the widely used Singular Spectrum Analysis (SSA) in the time series literature, and allows us to establish a rigorous link between time series analysis and matrix estimation. The key to establishing this link is constructing a Page matrix with non-overlapping entries rather than a Hankel matrix as is commonly done in the literature (e.g., SSA). This particular matrix structure allows us to provide finite sample analysis for imputation and prediction, and prove the asymptotic consistency of our method. Another salient feature of our algorithm is that it is model agnostic with respect to both the underlying time dynamics and the noise distribution in the observations. The noise agnostic property of our approach allows us to recover the latent states when only given access to noisy and partial observations a la a Hidden Markov Model; e.g., recovering the time-varying parameter of a Poisson process without knowing that the underlying process is Poisson. Furthermore, since our forecasting algorithm requires regression with noisy features, our approach suggests a matrix estimation based method---coupled with a novel, non-standard matrix estimation error metric---to solve the error-in-variable regression problem, which could be of interest in its own right. Through synthetic and real-world datasets, we demonstrate that our algorithm outperforms standard software packages (including R libraries) in the presence of missing data as well as high levels of noise.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122533641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Radulovic, Rommel Sánchez Verdejo, P. Carpenter, Petar Radojkovic, B. Jacob, E. Ayguadé
{"title":"PROFET: Modeling System Performance and Energy Without Simulating the CPU","authors":"M. Radulovic, Rommel Sánchez Verdejo, P. Carpenter, Petar Radojkovic, B. Jacob, E. Ayguadé","doi":"10.1145/3309697.3331502","DOIUrl":"https://doi.org/10.1145/3309697.3331502","url":null,"abstract":"Application performance on novel memory systems is typically estimated using a hardware simulator. The simulation is, however, time consuming, which limits the number of design options that can be explored within a practical length of time. Also, although memory simulators are typicallywell validated, current CPU simulators have various shortcomings, such as simplified out-of-order execution, an obsolete data prefetcher and a lack of virtual-to-physical memory translation, all of which can make a huge difference between the simulated and actual memory system.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130425134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Efficient Distributed Workload (Re-)Embedding","authors":"M. Henzinger, S. Neumann, S. Schmid","doi":"10.1145/3309697.3331503","DOIUrl":"https://doi.org/10.1145/3309697.3331503","url":null,"abstract":"Modern networked systems are increasingly reconfigurable, enabling demand-aware infrastructures whose resources can be adjusted according to the workload they currently serve. Such dynamic adjustments can be exploited to improve network utilization and hence performance, by moving frequently interacting communication partners closer, e.g., collocating them in the same server or datacenter. However, dynamically changing the embedding of workloads is algorithmically challenging: communication patterns are often not known ahead of time, but must be learned. During the learning process, overheads related to unnecessary moves (i.e., re-embeddings) should be minimized. This paper studies a fundamental model which captures the tradeoff between the benefits and costs of dynamically collocating communication partners on l servers, in an online manner. Our main contribution is a distributed online algorithm which is asymptotically almost optimal, i.e., almost matches the lower bound (also derived in this paper) on the competitive ratio of any (distributed or centralized) online algorithm.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123630831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lei Zhang, Zhemin Yang, Yuyu He, Mingqi Li, Sen Yang, Min Yang, Yuan Zhang, Zhiyun Qian
{"title":"App in the Middle: Demystify Application Virtualization in Android and its Security Threats","authors":"Lei Zhang, Zhemin Yang, Yuyu He, Mingqi Li, Sen Yang, Min Yang, Yuan Zhang, Zhiyun Qian","doi":"10.1145/3309697.3331517","DOIUrl":"https://doi.org/10.1145/3309697.3331517","url":null,"abstract":"Customizability is a key feature of the Android operating system that differentiates it from Apple's iOS. One concrete feature that gaining popularity is called \"app virtualization''. This feature allows multiple copies of the same app to be installed and opened simultaneously (e.g., with multiple accounts logged in). Virtualization frameworks are used by more than 100 million users worldwide. As with any new system features, we are interested in two aspects: (1) whether the feature itself introduces security risks and (2) whether the feature is abused for unintended purposes. This paper conducts a systematic study on the two aspects of the app virtualization techniques. With a thorough study of 32 popular virtualization frameworks from Google Play, we identify seven areas of potential attack vectors and find that most of the frameworks are susceptible to them. By deeply investigating their ecosystem, we show, with demonstrations, that attackers can easily distribute malware that takes advantage of these attack vectors. In addition, we show that the same virtualization techniques are also abused by malware as an alternative and easy-to-use repackaging mechanism. To this end, we design and implement a new app repackage detector. After scanning 250,145 apps from app markets, it finds 164 repackaged apps that attempt to steal user credentials and private data.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125069178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shoaib Akram, Jennifer B. Sartor, K. McKinley, L. Eeckhout
{"title":"Crystal Gazer: Profile-Driven Write-Rationing Garbage Collection for Hybrid Memories","authors":"Shoaib Akram, Jennifer B. Sartor, K. McKinley, L. Eeckhout","doi":"10.1145/3309697.3331492","DOIUrl":"https://doi.org/10.1145/3309697.3331492","url":null,"abstract":"Emerging non-volatile memory (NVM) technologies offer greater capacity than DRAM. Unfortunately, production NVM exhibits high latency and low write endurance. Hybrid memory combines DRAM and NVM to deliver greater capacity, low latency, high en- durance, and low energy consumption. Write-rationing garbage col- lection mitigates NVM wear-out by placing highly-written objects in DRAM and the rest in NVM. Existing write-rationing garbage collectors dynamically monitor object writes to place highly writ- ten objects in DRAM. Unfortunately, monitoring writes incurs a non-negligible performance overhead. This work proposes Crystal Gazer, profile-driven write-rationing garbage collection for hybrid memories. Allocation sites are statically profiled, and highly writ- ten objects are predicted based on previous program executions. Unlike prior work, this paper exposes a Pareto trade-off between DRAM usage and NVM lifetime. Experimental results on an emula- tion platform show that Crystal Gazer eliminates the performance overhead of dynamic monitoring, while reducing more NVM writes than state-of-the-art write-rationing garbage collectors.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116760637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hyper-Scalable JSQ with Sparse Feedback","authors":"Mark van der Boor, S. Borst, J. V. Leeuwaarden","doi":"10.1145/3311075","DOIUrl":"https://doi.org/10.1145/3311075","url":null,"abstract":"Load balancing algorithms play a vital role in enhancing performance in data centers and cloud networks. Due to the massive size of these systems, scalability challenges, and especially the communication overhead associated with load balancing mechanisms, have emerged as major concerns. Motivated by these issues, we introduce and analyze a novel class of load balancing schemes where the various servers provide occasional queue updates to guide the load assignment. We show that the proposed schemes strongly outperform JSQ(d) strategies with comparable communication overhead per job, and can achieve a vanishing waiting time in the many-server limit with just one message per job, just like the popular JIQ scheme. The proposed schemes are particularly geared however towards the sparse feedback regime with less than one message per job, where they outperform corresponding sparsified JIQ versions. We investigate fluid limits for synchronous updates as well as asynchronous exponential update intervals. The fixed point of the fluid limit is identified in the latter case, and used to derive the queue length distribution. We also demonstrate that in the ultra-low feedback regime the mean stationary waiting time tends to a constant in the synchronous case, but grows without bound in the asynchronous case.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129594837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Learning Graphs from Noisy Epidemic Cascades","authors":"Jessica Hoffmann, C. Caramanis","doi":"10.1145/3309697.3331511","DOIUrl":"https://doi.org/10.1145/3309697.3331511","url":null,"abstract":"Epidemic models accurately represent (among other processes) the spread of diseases, information (rumors, viral videos, news stories, etc.), the spread of malevolent agents in a network (computer viruses, malicious apps, etc.), or even biological processes (pathways in cell signaling networks, chains of activation in the gene regulatory network, etc.). We focus on epidemics that spread on an underlying graph [5].","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115403615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improved Queue-Size Scaling for Input-Queued Switches via Graph Factorization","authors":"Jiaming Xu, Y. Zhong","doi":"10.1017/apr.2020.31","DOIUrl":"https://doi.org/10.1017/apr.2020.31","url":null,"abstract":"This paper studies the scaling of the expected total queue size in an $ntimes n$ input-queued switch, as a function of both the load ρ and the system scale n. We provide a new class of scheduling policies under which the expected total queue size scales as Ołeft( n(1-ρ)^-4/3 łog łeft(maxfrac1 1-ρ, n right)right)$, over all n and ρ<1$, when the arrival rates are uniform. This improves over the previously best-known scalings in two regimes: Ołeft(n^1.5 (1-ρ)^-1 łog frac1 1-ρ right)$ when Ømega(n^-1.5 ) łe 1-ρ łe O(n^-1 )$ and $Ołeft(fracnłog n (1-ρ)^2 right)$ when $1-ρ geq Ømega(n^-1 ). A key ingredient in our method is a tight characterization of the largest k-factor of a random bipartite multigraph, which may be of independent interest.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128586122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Network Resilience Assessment via QoS Degradation Metrics: An Algorithmic Approach","authors":"Lan N. Nguyen, M. Thai","doi":"10.1145/3309697.3331470","DOIUrl":"https://doi.org/10.1145/3309697.3331470","url":null,"abstract":"This paper focuses on network resilience to perturbation of edge weight. Other than connectivity, many network applications nowadays rely upon some measure of network distance between a pair of connected nodes. In these systems, a metric related to network functionality is associated to each edge. A pair of nodes only being functional if the weighted, shortest-path distance between the pair is below a given threshold T. Consequently, a natural question is on which degree the change of edge weights can damage the network functionality? With this motivation, we study a new problem, Quality of Service Degradation : given a set of pairs, find a minimum budget to increase the edge weights which ensures the distance between each pair exceeds T. We introduce four algorithms with theoretical performance guarantees for this problem. Each of them has its own strength in trade-off between effectiveness and running time, which are illustrated both in theory and comprehensive experimental evaluation.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129220741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Osman Emre Dai, Daniel Cullina, N. Kiyavash, M. Grossglauser
{"title":"Analysis of a Canonical Labeling Algorithm for the Alignment of Correlated Erdős-Rényi Graphs","authors":"Osman Emre Dai, Daniel Cullina, N. Kiyavash, M. Grossglauser","doi":"10.1145/3309697.3331505","DOIUrl":"https://doi.org/10.1145/3309697.3331505","url":null,"abstract":"Graph alignment in two correlated random graphs refers to the task of identifying the correspondence between vertex sets of the graphs. Recent results have characterized the exact information-theoretic threshold for graph alignment in correlated Erdős-Rényi graphs. However, very little is known about the existence of efficient algorithms to achieve graph alignment without seeds. In this work we identify a region in which a straightforward $calO(n^11/5 łog n )$-time canonical labeling algorithm, initially introduced in the context of graph isomorphism, succeeds in aligning correlated Erdős-Rényi graphs. The algorithm has two steps. In the first step, all vertices are labeled by their degrees and a trivial minimum distance alignment (i.e., sorting vertices according to their degrees) matches a fixed number of highest degree vertices in the two graphs. Having identified this subset of vertices, the remaining vertices are matched using a alignment algorithm for bipartite graphs. Finally, we show that the implementation of a variant of this algorithm allows for the efficient alignment of large graphs under limited noise.","PeriodicalId":268462,"journal":{"name":"Abstracts of the 2019 SIGMETRICS/Performance Joint International Conference on Measurement and Modeling of Computer Systems","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129966460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}