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SSDs exhibit very different failure characteristics compared to hard drives. In particular, the bit error rate (BER) of an SSD climbs as it receives more writes. As a result, RAID arrays composed from SSDs are subject to correlated failures. By balancing writes evenly across the array, RAID schemes can wear out devices at similar times. When a device in the(More)
Existing empirical studies of Internet structure and path properties indicate that the Internet is tree-like. This work quantifies the degree to which at least two important Internet measures--latency and bandwidth--approximate tree metrics. We evaluate our ability to model end-to-end measures using tree embeddings by actually building tree representations.(More)
Choosing a cloud storage system and specific operations for reading and writing data requires developers to make decisions that trade off consistency for availability and performance. Applications may be locked into a choice that is not ideal for all clients and changing conditions. Pileus is a replicated key-value store that allows applications to declare(More)
CORFU 1 organizes a cluster of flash devices as a single, shared log that can be accessed concurrently by multiple clients over the network. The CORFU shared log makes it easy to build distributed applications that require strong consistency at high speeds, such as databases, transactional key-value stores, replicated state machines, and metadata services.(More)
We present Griffin, a hybrid storage device that uses a hard disk drive (HDD) as a write cache for a Solid State Device (SSD). Griffin is motivated by two observations: First, HDDs can match the sequential write bandwidth of mid-range SSDs. Second, both server and desktop work-loads contain a significant fraction of block overwrites. By maintaining a(More)
Cell phones connected to high-speed 3G networks constitute an increasingly important class of clients on the Internet. From the viewpoint of the servers they connect to, such devices are virtually indistinguishable from conventional end-hosts. In this study, we examine the IP addresses seen by Internet servers for cell phone clients and make two(More)
Flooding is an important communication primitive in mobile ad-hoc networks and also serves as a building block for more complex protocols such as routing protocols. In this paper, we propose a novel approach to flooding, which relies on proactive compensation packets periodically broadcast by every node. The compensation packets are constructed from dropped(More)
Distributed systems are easier to build than ever with the emergence of new, data-centric abstractions for storing and computing over massive datasets. However, similar abstractions do not exist for storing and accessing meta-data. To fill this gap, Tango provides developers with the abstraction of a replicated, in-memory data structure (such as a map or a(More)
The Smoke and Mirrors File System (SMFS) mirrors files at geographically remote datacenter locations with negligible impact on file system performance at the primary site, and minimal degradation as a function of link latency. It accomplishes this goal using wide-area links that run at extremely high speeds, but have long round-trip-time latencies—a(More)
Mobile devices are increasingly used for social networking applications, where data is shared between devices belonging to different users. Today, such applications are implemented as centralized services, forcing users to trust corporations with their personal data. While decentralized designs for such applications can provide privacy, they are difficult(More)