PERFORMANCE AND TURBOWRITE TECHNOLOGY
Turbowrite is brand new to the Samsung EVO SSD and is a caching mechanism that increases the performance of the EVO immediately and has a measurable result. Where last gen’s 840 120GB SSD was only capable of 130MB/s high sequential write data transfer speed, the 840 EVO triples that to 410MB/s. This is the direct result of Samsung TurboWrite and this performance has never been seen prior except where compression was used in the drives storage. The performance upgrade between the 840 and 840 EVO is evident in the specifications and comparison chart shown here:
Performance of the 840 EVO is variable and dependent on capacity. Those seeking smaller capacity SSDs will be very surprised at the speeds Samsung has squeezed out of their 120 and 250GB SSDs through implementation of TurboWrite Technology, the performance improvement documented in product specs. While read performance remains consistent, the 840 EVO 120GB SSD has more than 3x the write performance of the same capacity of last generation (410/130) while the 250GB is a bit less with a 2x performance jump (520/250).
TurboWrite is a product of Samsung’s firmware where a small portion of each SSDs memory is used as simulated SLC NAND flash memory. During data transfer, a high performance write buffer is created by TurboWrite where write data is held within the buffer, completing its trip to the memory when idle time occurs in the drive. This increases the speed of data transfer significantly. The size of the TurboWrite buffer varies depending on capacity of the solid state drive and the various buffer sizes can be seen in this slide from the Global Summit:
The size of the buffer is key to data transfer and should the buffer become full or should a file require storage that is larger than the buffer size, that data will be stored outside the buffer and in real time at a slower level than that in the buffer. Once the buffer is cleared, write performance will resume at the higher speeds. This chart displays the speed of data transfer while TurboWrite is in play and while it is not:
Probably the biggest takeaway with TurboWrite is that its effect is immediate, can be measured and is noticeable. Technically, Samsung didn’t even have to speak of TurboWrite and the consumer would have simply believed that Samsung has upped the ante with their low capacity drives. From our perspective, this is refreshing as too many times in the past companies have introduced this or that caching solution where the results couldn’t be immediately observed or were simply some small boot time increase.