Transcend SSD370 (128GB, 256GB & 512GB) Review

Performance Consistency

Performance consistency tells us a lot about the architecture of these SSDs and how they handle internal fragmentation. The reason we do not have consistent IO latency with SSDs is because inevitably all controllers have to do some amount of defragmentation or garbage collection in order to continue operating at high speeds. When and how an SSD decides to run its defrag or cleanup routines directly impacts the user experience as inconsistent performance results in application slowdowns.

To test IO consistency, we fill a secure erased SSD with sequential data to ensure that all user accessible LBAs (Logical Block Addresses) have data associated with them. Next we kick off a 4KB random write workload across all LBAs at a queue depth of 32 using incompressible data. The test is run for just over half an hour and we record instantaneous IOPS every second.

We are also testing drives with added over-provisioning by limiting the LBA range. This gives us a look into the drive’s behavior with varying levels of empty space, which is frankly a more realistic approach for client workloads.

Each of the three graphs has its own purpose. The first one is of the whole duration of the test in log scale. The second and third one zoom into the beginning of steady-state operation (t=1400s) but on different scales: the second one uses log scale for easy comparison whereas the third one uses linear scale for better visualization of differences between drives. Click the dropdown selections below each graph to switch the source data.

For more detailed description of the test and why performance consistency matters, read our original Intel SSD DC S3700 article.

Default	Transcend SSD370 256GBTranscend SSD370 512GBADATA Premier SP610 256GBADATA Premier SP610 512GBCorsair Force LS 240GBCorsair Neutron XT 240GBCorsair Neutron XT 480GBCorsair Neutron XT 960GBCrucial MX100 256GBCrucial MX100 512GBIntel SSD 730 480GBIntel SSD Pro 2500 240GBJMicron JMF667H 240GBMicron M600 256GBMicron M600 1TBOCZ ARC 100 240GBOCZ Vector 150 240GBOCZ Vertex 460 240GBOCZ RevoDrive 350 480GBPlextor M6S 256GBSamsung SSD 840 EVO 250GBSamsung SSD 840 EVO mSATA 1TBSamsung SSD 850 EVO 250GBSamsung SSD 850 EVO 500GBSamsung SSD 850 EVO 1TBSamsung SSD 850 Pro 256GBSamsung SSD 850 Pro 1TBSamsung XP941 256GBSamsung XP941 512GBSanDisk Ultra II 240GBSanDisk Extreme Pro 240GBSanDisk Extreme Pro 480GBSanDisk Extreme Pro 960GBSanDisk Extreme II 480GBSanDisk Ultra Plus 256GB
25% Over-Provisioning	Transcend SSD370 256GBTranscend SSD370 512GBADATA Premier SP610 256GBADATA Premier SP610 512GBCorsair Force LS 240GBCorsair Neutron XT 240GBCorsair Neutron XT 480GBCorsair Neutron XT 960GBCrucial MX100 256GBCrucial MX100 512GBIntel SSD 730 480GBIntel SSD Pro 2500 240GBJMicron JMF667H 240GBMicron M600 256GBMicron M600 1TBOCZ ARC 100 240GBOCZ Vector 150 240GBOCZ Vertex 460 240GBOCZ RevoDrive 350 480GBPlextor M6S 256GBSamsung SSD 840 EVO mSATA 1TBSamsung SSD 850 EVO 250GBSamsung SSD 850 EVO 500GBSamsung SSD 850 EVO 1TBSamsung SSD 850 Pro 256GBSamsung SSD 850 Pro 1TBSamsung XP941 256GBSamsung XP941 512GBSanDisk Ultra II 240GBSanDisk Extreme Pro 240GBSanDisk Extreme Pro 480GBSanDisk Extreme Pro 960GBSanDisk Extreme II 480GBSanDisk Ultra Plus 256GB

Despite the custom Transcend firmware, performance consistency is an exact match with ADATA's SP610. I'm suspecting that the reason for low steady-state performance might be the hardware because the SM2246EN is a single-core design. Most controller designs today are multicore because today's NAND requires a lot of management and with multiple cores the NAND management can be dedicated to one or more cores, which leaves the rest of the cores available for host IO processing. In Silicon Motion's case, the one core has to take care of everything from host IOs to NAND management, which translates to lower overall performance as the controller can't keep up with everything that needs to be done.

Default	Transcend SSD370 256GBTranscend SSD370 512GBADATA Premier SP610 256GBADATA Premier SP610 512GBCorsair Force LS 240GBCorsair Neutron XT 240GBCorsair Neutron XT 480GBCorsair Neutron XT 960GBCrucial MX100 256GBCrucial MX100 512GBIntel SSD 730 480GBIntel SSD Pro 2500 240GBJMicron JMF667H 240GBMicron M600 256GBMicron M600 1TBOCZ ARC 100 240GBOCZ Vector 150 240GBOCZ Vertex 460 240GBOCZ RevoDrive 350 480GBPlextor M6S 256GBSamsung SSD 840 EVO 250GBSamsung SSD 840 EVO mSATA 1TBSamsung SSD 850 EVO 250GBSamsung SSD 850 EVO 500GBSamsung SSD 850 EVO 1TBSamsung SSD 850 Pro 256GBSamsung SSD 850 Pro 1TBSamsung XP941 256GBSamsung XP941 512GBSanDisk Ultra II 240GBSanDisk Extreme Pro 240GBSanDisk Extreme Pro 480GBSanDisk Extreme Pro 960GBSanDisk Extreme II 480GBSanDisk Ultra Plus 256GB
25% Over-Provisioning	Transcend SSD370 256GBTranscend SSD370 512GBADATA Premier SP610 256GBADATA Premier SP610 512GBCorsair Force LS 240GBCorsair Neutron XT 240GBCorsair Neutron XT 480GBCorsair Neutron XT 960GBCrucial MX100 256GBCrucial MX100 512GBIntel SSD 730 480GBIntel SSD Pro 2500 240GBJMicron JMF667H 240GBMicron M600 256GBMicron M600 1TBOCZ ARC 100 240GBOCZ Vector 150 240GBOCZ Vertex 460 240GBOCZ RevoDrive 350 480GBPlextor M6S 256GBSamsung SSD 840 EVO mSATA 1TBSamsung SSD 850 EVO 250GBSamsung SSD 850 EVO 500GBSamsung SSD 850 EVO 1TBSamsung SSD 850 Pro 256GBSamsung SSD 850 Pro 1TBSamsung XP941 256GBSamsung XP941 512GBSanDisk Ultra II 240GBSanDisk Extreme Pro 240GBSanDisk Extreme Pro 480GBSanDisk Extreme Pro 960GBSanDisk Extreme II 480GBSanDisk Ultra Plus 256GB

Default	Transcend SSD370 256GBTranscend SSD370 512GBADATA Premier SP610 256GBADATA Premier SP610 512GBCorsair Force LS 240GBCorsair Neutron XT 240GBCorsair Neutron XT 480GBCorsair Neutron XT 960GBCrucial MX100 256GBCrucial MX100 512GBIntel SSD 730 480GBIntel SSD Pro 2500 240GBJMicron JMF667H 240GBMicron M600 256GBMicron M600 1TBOCZ ARC 100 240GBOCZ Vector 150 240GBOCZ Vertex 460 240GBOCZ RevoDrive 350 480GBPlextor M6S 256GBSamsung SSD 840 EVO 250GBSamsung SSD 840 EVO mSATA 1TBSamsung SSD 850 EVO 250GBSamsung SSD 850 EVO 500GBSamsung SSD 850 EVO 1TBSamsung SSD 850 Pro 256GBSamsung SSD 850 Pro 1TBSamsung XP941 256GBSamsung XP941 512GBSanDisk Ultra II 240GBSanDisk Extreme Pro 240GBSanDisk Extreme Pro 480GBSanDisk Extreme Pro 960GBSanDisk Extreme II 480GBSanDisk Ultra Plus 256GB
25% Over-Provisioning	Transcend SSD370 256GBTranscend SSD370 512GBADATA Premier SP610 256GBADATA Premier SP610 512GBCorsair Force LS 240GBCorsair Neutron XT 240GBCorsair Neutron XT 480GBCorsair Neutron XT 960GBCrucial MX100 256GBCrucial MX100 512GBIntel SSD 730 480GBIntel SSD Pro 2500 240GBJMicron JMF667H 240GBMicron M600 256GBMicron M600 1TBOCZ ARC 100 240GBOCZ Vector 150 240GBOCZ Vertex 460 240GBOCZ RevoDrive 350 480GBPlextor M6S 256GBSamsung SSD 840 EVO mSATA 1TBSamsung SSD 850 EVO 250GBSamsung SSD 850 EVO 500GBSamsung SSD 850 EVO 1TBSamsung SSD 850 Pro 256GBSamsung SSD 850 Pro 1TBSamsung XP941 256GBSamsung XP941 512GBSanDisk Ultra II 240GBSanDisk Extreme Pro 240GBSanDisk Extreme Pro 480GBSanDisk Extreme Pro 960GBSanDisk Extreme II 480GBSanDisk Ultra Plus 256GB

TRIM Validation

To test TRIM, I filled a 128GB SSD370 with sequential 128KB data and proceeded with a 30-minute random 4KB write (QD32) workload to put the drive into steady-state. After that I TRIM'ed the drive by issuing a quick format in Windows and ran HD Tach to produce the graph below.

And TRIM works as expected.