A couple of comments on your testing procedure. - Please version everything you use : fio, kernel, system, bios, ssd firmware All this can have an impact on your testing. It's unclear if they all run of the same host/setup or not. - Please expose the device size as the ssd model/brand isn't enough. The size of the SSD have a huge impact on its performance You should also expose the DWPD of these drive to detail how much endurant they are supposed to be. The public price could be also a hint for the reader. - Please expose the SMART attributes of these drives If some are older than other, the wear leveling status could impact the performance too - Why do you enforce iodepth to 1 ? SSD devices can perfectly handle much more than that, and that what will happen when used by the OS. I'd suggest to run at least iodepth = 32. - Please expose the device configuration with a sdparm -a (to know what are the read & write cache settings on this devices) - Starting from the fresh erased disk would be better to start from a clear device (same TRIM state on all devices) On 29/01/2020 23:43, Louwrentius wrote: > Hello, > > I've done some benchmarks with FIO of entire SSD devices. So the FIO > benchmark stops when the whole device has been read/written. I've > logged latency and iops for the entire run. > > Those logs are then translated to graphs. The Intel SSD shows the kind > of graph I would expect. The Samsung and Kingston SSDs show 'strange' > results. > > I've written a brief blog article about this which includes links to > the raw data and the images. > https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Flouwrentius.com%2Fdifference-of-behavior-in-sata-solid-state-drives.html&data=02%7C01%7Ce.velu%40criteo.com%7C0bfd1acab1454841fad208d7a50ca983%7C2a35d8fd574d48e3927c8c398e225a01%7C1%7C1%7C637159346115224065&sdata=DzEZDHTfCk6tpEsYacMRETj5rUbRoLRtQu7yUW%2BeV3M%3D&reserved=0 > > Does anybody have an idea what could be going on? Why do we see these > 'golden gate bridge' patterns? Maybe I did something wrong? > > With regards, > > Louwrentius
