Review on Silicon Power Slim S55 120GB SATA SP120GBSS3S55S25 SSD by Mateusz Grzesiak  (M ᠌

Report on the real speeds of this SSD. Tested with the fio utility, under Linux. Queue depth everywhere 128, noop scheduler, merge requests in queue for test disabled. 1) Sequential reading in the ideal case (in blocks >= 256kb) - 550 Mb / s 2) Sequential reading in blocks of 4k - an average of 190 Mb / s, but decently fluctuates between 170-280 Mb / s 3) Sequential reading in blocks of 8k - 370 Mb / s; 16k - 450 Mb/s; 32k - 500 Mb/s; 64k - 530 Mb/s; 128k - 540 Mb / s. Here, all the figures are absolutely stable, they do not fluctuate. 4) Random reading in blocks of 4k - 170 Mb / s (~ 41000 iops), also fluctuates between 120-220 Mb / s. 5) Random reading in blocks of 8k - 305 Mb / s. For 16k - 340 Mb / s. At 32k - 380 Mb / s. For 64k - 440 Mb / s. At 128k - 510 Mb / s. At 256k - 535 Mb / s (this is actually sequential reading, not random). Here the speed is again stable, almost without fluctuations. 6) There is a "pseudo-SLC cache". Sequential recording of the first 2.4 GB in 4k blocks - 244 Mb / s. Large blocks (>= 256k) - 490 Mb/s. 7) After 2.4 GB, the write settles at 95 Mb/s, regardless of the block size (SLC cache ends). 8) Random write speed is absolutely identical to sequential write speed. 9) The recording speed is kept constant, including after a complete rewriting of the entire disc. 10) 30 seconds of idle time is enough for the SLC cache to reset and write back to 490 MB/s.