TY - GEN
T1 - Providing QoS through host controlled flash SSD garbage collection and multiple SSDs
AU - Shin, Woong
AU - Kim, Myeongcheol
AU - Kim, Kyudong
AU - Yeom, Heon Y.
N1 - Publisher Copyright:
© 2015 IEEE.
PY - 2015/3/30
Y1 - 2015/3/30
N2 - In this work, we optimize the highly variable latency of flash SSDs by presenting a host side storage engine, which is capable of cooperating with the SSDs, and augmented by the redundancy of multiple SSD instances. The storage engine schedules I/O and SSD internal operations to data blocks replicated among multiple SSDs exploiting the support of an SSD control API provided by off-the-shelf SATA 6.0 Gb/s MLC SSDs extended with modest firmware modifications. Side effects of latency heavy operations such as garbage collection (GC) are detained in a group of physical SSDs, while foreground operations are diverted to other SSDs. This way, flash SSDs can keep up with demands of free blocks, even under workloads without idle time, without harming foreground application latency. In our evaluations, our storage engine enhanced the latency stability of flash SSDs by 40 times, decreasing the 99.9999th percentile latency to sub milli-second levels. Also, our storage engine, when integrated into a flash SSD based in-memory system, was capable of reducing the 99th percentile of application latency by 4.5 times.
AB - In this work, we optimize the highly variable latency of flash SSDs by presenting a host side storage engine, which is capable of cooperating with the SSDs, and augmented by the redundancy of multiple SSD instances. The storage engine schedules I/O and SSD internal operations to data blocks replicated among multiple SSDs exploiting the support of an SSD control API provided by off-the-shelf SATA 6.0 Gb/s MLC SSDs extended with modest firmware modifications. Side effects of latency heavy operations such as garbage collection (GC) are detained in a group of physical SSDs, while foreground operations are diverted to other SSDs. This way, flash SSDs can keep up with demands of free blocks, even under workloads without idle time, without harming foreground application latency. In our evaluations, our storage engine enhanced the latency stability of flash SSDs by 40 times, decreasing the 99.9999th percentile latency to sub milli-second levels. Also, our storage engine, when integrated into a flash SSD based in-memory system, was capable of reducing the 99th percentile of application latency by 4.5 times.
KW - Design
KW - Flash
KW - Flash based In-memory Systems
KW - Garbage Collection
KW - Memcached
KW - Performance
KW - SSD
KW - YCSB
UR - http://www.scopus.com/inward/record.url?scp=84928162061&partnerID=8YFLogxK
U2 - 10.1109/35021BIGCOMP.2015.7072819
DO - 10.1109/35021BIGCOMP.2015.7072819
M3 - Conference contribution
AN - SCOPUS:84928162061
T3 - 2015 International Conference on Big Data and Smart Computing, BIGCOMP 2015
SP - 111
EP - 117
BT - 2015 International Conference on Big Data and Smart Computing, BIGCOMP 2015
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2015 International Conference on Big Data and Smart Computing, BIGCOMP 2015
Y2 - 9 February 2015 through 11 February 2015
ER -