Information Technology Reference
In-Depth Information
Size
Capacity
300 GB
Page Size
4KB
Performance
Bandwidth (Sequential Reads)
270 MB/s
Bandwidth (Sequential Writes)
210 MB/s
Read/Write Latency
75 s
Random Reads Per Second
38,500
Random Writes Per Second
2,000 (2,400 with 20% space reserve)
Interface
SATA 3 Gb/s
Endurance
Endurance
1.1 PB (1.5 PB with 20% space reserve)
Power
Power Consumption Active/Idle
3.7 W / 0.7 W
Figure12.6: Key parameters for an Intel 710 Series Solid State Drive manu-
factured in 2011.
The sequential performance of this drive is very good, with peak sustained
read and write bandwidths of 270 MB/s and 210 MB/s respectively. In com-
parison, a high-end Seagate Cheetah 15K.7 drive manufactured in 2010 spins at
15,000 revolutions per second and provides 122 MB/s to 204 MB/s of sustained
bandwidth.
Random read performance is excellent. The latency for a single random
4 KB read is just 75 s, and when multiple concurrent requests are in ight,
the drive can process 38,500 random reads per second|one every 26 s. This
is orders of magnitude better than the random read performance of a spinning
disk drive.
Random write performance is also very good, but not as good as random
read performance. The latency for a single random 4 KB write is 75 s; the
drive reduces write latency by buffering writes in volatile memory, and it has
capaciters that store enough charge to write all buffered updates to flash storage
if a power loss occurs.
When multiple concurrent writes are in flight, the drive can process 2,000
random writes writes per second when it is full; if it is less than 80% full, that
number rises to 2,400. Random write throughput increases when the drive has
more free space because the drive has to garbage collect live pages from erasure
blocks less often and because when the drive eventually does do that garbage
collection, the erasure blocks are less full.
The drive's is rated for 1.1 PB (1.1 10
15
bytes) of endurance (1.5 PB if it
is less than 80% full.) For many workloads, this endurance suces for years or
decades of use. However, solid state drives may not always be a good match
for high-bandwidth write streaming. In the extreme, an application constantly
