"As you probably know there is a trend in enterprise computing towards networked storage. This is illustrated by the emergence during the past few years of standards like SRP (SCSI RDMA Protocol), iSCSI (Internet SCSI) and iSER (iSCSI Extensions for RDMA)," began Bart Van Assche, proposing that SCST be merged into the mainline kernel. He suggested that while similar to the STGT project which has been part of the mainline kernel since 2.6.20, "SCST is superior to STGT with respect to features, performance, maturity, stability, and number of existing target drivers. Unfortunately the SCST kernel code lives outside the kernel tree, which makes SCST harder to use than STGT."
SCSI subsystem maintainer, James Bottomley, was not convinced, explaining:
"The two target architectures perform essentially identical functions, so there's only really room for one in the kernel. Right at the moment, it's STGT. Problems in STGT come from the user<->kernel boundary which can be mitigated in a variety of ways. The fact that the figures are pretty much comparable on non IB networks shows this. I really need a whole lot more evidence than at worst a 20% performance difference on IB to pull one implementation out and replace it with another. Particularly as there's no real evidence that STGT can't be tweaked to recover the 20% even on IB."