TRIM Performance:
While SSDs offer many benefits, there are some downsides to using flash memory. One of the biggest issues people run into is performance degradation. Over time, an SSD will run out of fresh blocks and will have to write over data the file system has marked as deleted. This procedure is very complicated and can slow an SSD's write speeds considerably.
To address this problem, most manufacturers have added TRIM support to their SSDs. The TRIM command allows an operating system, such as Windows 7, to tell an SSD which data blocks are no longer in use. Using this information, the drive pro-actively erases these blocks and adds them to the free block pool.
To test the Ultra Plus' TRIM function, I first put the drive in a "dirty" state. I used Iometer to fill the entire drive and then ran a random write test for 30 minutes. This had very little effect on the Ultra Plus' read speed. However, its average write speed dropped to a mere 30.3 MB/s.
SanDisk Ultra Plus SSD - Dirty
To see how well the Ultra Plus could recover, I let the computer sit for a few hours and then reran the test. The drive wasn't able to reach the factory fresh performance shown in our earlier tests. However, its average write speed climbed up to 180.7 MB/s.
SanDisk Ultra Plus SSD - After Trim
Lastly, I used Parted Magic to perform a secure erase on the Ultra Plus. With the drive wiped clean, its write speed jumped back up to 321.8 MB/s.
SanDisk Ultra Plus SSD - Secure Erase
Final Thoughts:
The SanDisk Ultra Plus SSD is a welcome change from the myriad of "SandForce Driven" SSDs on the market today. This ultra-slim drive combines Marvell's 88SS9175 controller with SanDisk's own 19nm eX2 ABL MLC NAND flash to deliver a fast, responsive computing experience at an affordable price. In our sequential read and write tests, the Ultra Plus was able to read at speeds as high as 531 MB/s and write at speeds in excess of 430 MB/s. It also performed very well when doing random reads, but lagged behind the other drives in our random write tests, producing only 39,000 IOPS. This may be a deal breaker for some, but the Ultra Plus is still a huge improvement over traditional hard drives and a worthy upgrade for older notebook and desktop computers.
The SanDisk Ultra Plus SSD is available now in 64GB, 128GB and 256GB capacities. The 128GB drive currently retails for about $103 with the 256GB version reviewed here going for less than $170 on Amazon.
Highs:
- Available in 64GB, 128GB and 256GB capacities
- Marvell 88SS9175 controller
- Features nCache Technology
- Good sequential read and write speeds
- Performs equally well with compressible and incompressible data
- SATA 6Gb/s interface
- 128MB DRAM Cache
- Supports TRIM, garbage collection and wear leveling
- Ultra-slim form factor
- Reasonably priced
- 3 year warranty
Lows:
- Mediocre random write performance
