With the expanding data storage capacity needs, DNA as an alternative to the archival storage medium offers potential advantages, including higher density and data retention for information storage1,2. However, the majority of DNA-based memory systems are write-once and read-only, although few studies have suggested overwriting digital data on the existing DNA using chemical modifications of bases 3. Using those strategies requires constantly updating the entire data coding and iteratively synthesizing the DNA pool. Therefore, considering the complexity and cost, those methods needed some amendments to become industrially scalable. Inspired by magnetic tapes4 and multisession-CD5, in this work, we created a DNA storage system coined the Molecular File System (MolFS), to organize, store, and edit digital information in a DNA pool. MolFS uses DNA pools that consist of multiple sessions, where each session contains data block and unique index sections to store and edit the files. We used indexes to describe the file system hierarchy, locate files along with the blocks, recognize the sessions, and identify the file versions. This approach reduces the editing cost compared to the state-of-the-art methods, and editing or adding data requires only synthesizing a new DNA pool containing the DNA session of the differential file. As proof of concept, we encoded 2.3 Kbytes of graphic and text data into 2 DNA pools. To edit the existing DNA pool, we added 8 new differential data blocks to existing pools, reaching 13.8 Kbytes of data stored from sessions 1 to 5. We performed nanopore sequencing and recovered the data from the MolFS sessions accurately and precisely.
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Baoverlay: a block-accessible overlay file system for fast and efficient container storage
Container storage commonly relies on overlay file systems to interpose read-only container images upon backing file systems. While being transparent to and compatible with most existing backing file systems, the overlay file-system approach imposes nontrivial I/O overhead to containerized applications, especially for writes: To write a file originating from a read-only container image, the whole file will be copied to a separate, writable storage layer, resulting in long write latency and inefficient use of container storage. In this paper, we present BAOverlay, a lightweight, block-accessible
overlay file system: Equipped with a new block-accessibility attribute, BAOverlay not only exploits the benefit of using an asynchronous copy-on-write mechanism for fast file
updates but also enables a new file format for efficient use of container storage space. We have developed a prototype of BAOverlay upon Linux Ext4. Our evaluation with both
micro-benchmarks and real-world applications demonstrates the effectiveness of BAOverlay with improved write performance and on-demand container storage usage.
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- Award ID(s):
- 1909877
- NSF-PAR ID:
- 10297237
- Date Published:
- Journal Name:
- Proceedings of the 11th ACM Symposium on Cloud Computing (SoCC 2020)
- Page Range / eLocation ID:
- 90 to 104
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1145/3419111.3421291
