Title
RIPQ: Advanced Photo Caching on Flash for Facebook.
Abstract
Facebook uses flash devices extensively in its photo-caching stack. The key design challenge for an efficient photo cache on flash at Facebook is its workload: many small random writes are generated by inserting cache-missed content, or updating cache-hit content for advanced caching algorithms. The Flash Translation Layer on flash devices performs poorly with such a workload, lowering throughput and decreasing device lifespan. Existing coping strategies under-utilize the space on flash devices, sacrificing cache capacity, or are limited to simple caching algorithms like FIFO, sacrificing hit ratios. We overcome these limitations with the novel Restricted Insertion Priority Queue (RIPQ) framework that supports advanced caching algorithms with large cache sizes, high throughput, and long device lifespan. RIPQ aggregates small random writes, co-locates similarly prioritized content, and lazily moves updated content to further reduce device overhead. We show that two families of advanced caching algorithms, Segmented-LRU and Greedy-Dual-Size-Frequency, can be easily implemented with RIPQ. Our evaluation on Facebook's photo trace shows that these algorithms running on RIPQ increase hit ratios up to ∼20% over the current FIFO system, incur low overhead, and achieve high throughput.
Year
Venue
Field
2015
FAST
Flash file system,FIFO (computing and electronics),Cache capacity,Workload,Cache,Computer science,Parallel computing,Cache algorithms,Real-time computing,Priority queue,Throughput
DocType
Citations 
PageRank 
Conference
25
0.72
References 
Authors
34
5
Name
Order
Citations
PageRank
Linpeng Tang1251.05
Qi Huang223515.66
Wyatt Lloyd371427.53
Sanjeev Kumar42727139.04
Kai Li55345435.41