On Fri, Oct 21, 2016 at 8:07 PM, Elliott, Robert (Persistent Memory) <elliott@xxxxxxx> wrote: >> -----Original Message----- >> From: fio-owner@xxxxxxxxxxxxxxx [mailto:fio-owner@xxxxxxxxxxxxxxx] On Behalf >> Of Tarek >> Sent: Thursday, October 20, 2016 8:31 PM >> Subject: Results too good to be true? >> >> 10 NVME Intel DC P3600 spec'd at 450K Random Read 32QD 4 Jobs >> I ran 128QD, 3 Jobs each and got aggregate total of iops=7039.3K! >> That's more than the spec (granted they didn't spec it for 128QD). >> Results below and Fio File below that can you take a look >> if I am overlooking something? > > If you want to match the data sheet, you should replicate the > data sheet's test conditions: 4 jobs with a queue depth of 32. > > http://www.anandtech.com/show/8104/intel-ssd-dc-p3700-review-the-pcie-ssd-transition-begins-with-nvme/3 shows the P3700 is better at QD 128 for random reads: > * 1125 MB/s at QD 32 > * 1875 MB/s at QD 128 > > so you might be seeing a similar effect. > > Also, since the data sheet mentions iometer, they must have used > Windows. Windows and linux drivers don't always deliver equal > performance. > Have the drives been preconditioned? Reads won't make it all the way to the nand if the mapping table is empty so you need to fill each drive with data first (preconditioning) and then run your test. -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
