Should You Always Use Read Intensive SSDs?

Posted by Ryan Brown on Feb 25, 2019

When it comes to Solid State Drives (SSDs), what does Read Intensive (RI), Mixed Use (MU), and Write Intensive (WI) really mean? Are RI SSDs the best and only option for read applications? If you’re doing read and write applications, do you need a Mixed Use drive? Below is charted data that compares the Performance, Endurance, Random Reads, and Random Writes between RI, MU, and WI SSDs.

Read Intensive (RI)

Looking at the RI drives listed below, you see endurance at 1 DWPD, Random Read IOPS at roughly 200K, and Random Write IOPS at roughly 35K. When we have talked to businesses about their workloads, we found many can use a read intensive drive even with a mixed workload. They don’t write enough data to exceed the endurance levels and the IOPS meet their needs. If you can use a RI drive, take a look at the 3.84TB SSDs. You get good performance and save drive bays for future needs.

Description Endurance DWPD 5 Years Endurance TBW (TB) Random Read 4KB (IOPS) Random Write 4KB (IOPS)
960GB 12Gbps SAS MLC PX05SRB096Y 1 1752 200K 30K
1.92TB 12Gbps SAS TLC PM1633a 1 3504 201K 37K
1.92TB 12Gbps SAS MLC PX05SRB192Y 1 3504 200K 35K
3.84TB 12Gbps SAS TLC PM1633a 1 7008 201K 37K
3.84TB 12Gbps SAS MLC PX05SRB384Y 1 7008 190K 35K

Mix Use (MU)

Comparatively, the Mix Use drive has the same Random Read IOPS as the Read Intensive drives, but out performs the RI drives in Random Writes and Endurance. Because you don’t sacrifice any Read IOPS, the MU drives can be used in similar read intensive workloads and you get the benefit of longer endurance. If you are a business that is going to keep your server for more than 5 years, MU drives may be your better option even in read intensive workloads.

Description Endurance DWPD 5 Years Endurance TBW (TB) Random Read 4KB (IOPS) Random Write 4KB (IOPS)
400GB 12Gbps SAS TLC PM1635a 3 2190 199K 61K

Write Intensive (WI)

Like the Mix Use drive, the Write Intensive drives have the same IOPS as the Read Intensive drives when it comes to Random Reads. The WI drives out performs both RI and MU drives in Endurance and Random Writes. You could technically use a WI drive in a read intensive workload because you don’t lose any performance, but the increased endurance would be overkill. Using WI drives in a mix use workload gives you longer life out of your drives and better write performance. Like the MU example above, this is definitely something to consider if you keep servers more than 5 years. If you do have a truly write intensive workload, the 800GB WI drive is an amazing value. Compared to the large 3.84TB RI drive, you get double the writes on the drive (14600 TBW compared to 7008 TBW) for half the cost.

Description Endurance DWPD 5 Years Endurance TBW (TB) Random Read 4KB (IOPS) Random Write 4KB (IOPS)
400GB 12Gbps SAS MLC PX05SMB040 10 7300 200K 109K
800GB 12Gbps SAS MLC PX055MB080Y 10 14600 200K 113K

When making a decision of which drive you should purchase, run Live Optics to understand your needs and then consult with one of our engineers to make sure you get the best value for you budget, workload, and your server's life expectancy.