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Showing posts with the label SAS 6/iR

Dell, how I hate thee (let me count the ways)

A Dell "feature" that appears to be designed to force customers to use only Dell parts reduced the speed of a set of SSDs one of my customers installed on their rack-mountable R900 server by a factor of 1000. Before I get into this, there are some provisos. This server was using Linux kernel 2.6.32. The SSDs involved are Samsung 850 Pro SATA-style solid state disks. SSD is not quite ready for prime time in the 2.6.32 kernel; NVMe support was first added in 3.3, TRIM wasn't available at all until 2.6.33, and a ton of other things we all take for granted like the device mapper are part of the 4.* kernel. Consumer-level Samsung drivers bring their own issues. Despite what the knuckle-heads on Reddit have to say about the topic, the Linux kernel still blacklists queued TRIM functions from every Samsung SSD in the 8** series. As of the latest Github commit as of this writing for kernel 4.8 queued TRIM still doesn't work for these devices. More importantly, the R900