Dependable SCSI RAID Controllers for Linux?

PalmKiller asks: "I have been using DPT (now Adaptec) SmartRaid controllers for years with great results in Linux, but with the advent of the Adaptec assimilation they became more unreliable in current kernels (in the 2.2 or 2.4 tree)...at least for the DPT SmartRaid V and Adaptec branded equivalents, ie: the kernel panics under stress...you know when you try to use it for anything but an idle uptime box. The crashes have something to do with 5 minute long command queues creating havoc in the kernel. I have a few SmartRaid IV controllers that plug away without issue, but they use a different driver. I suspect the programmers and people who knew how to program the Adaptec/DPT controllers got lost in the buyout, or perhaps driver quality control took a dive. I would greatly appreciate other Slashdot readers opinions on a good replacement that is available in the US."

"I have been considering ICP Vortex RZ and RS series and AMI Megaraid as possibles, along with the Mylex line of controllers. I would like some opinions, praises and even nightmare stories on any of these. I am not wanting to invest $350-$1500 per controller on another nightmare like Adaptec/DPT line. It should be obvious but cost is not primary, reliability and to a lesser degree performance are the key issues. In addition I run my controllers in RAID 5 with a hot spare, so suggestions should be for controllers that can do that RAID mode and ones that can be administered from a running Linux system so I can do hot swapping. I would also like controllers whose manufacturer keeps current patches available for the stock kernel tree or is in the kernel tree (for both 2.2 and 2.4, I use 2.2 mostly due to issues with 2.4) as I never use a canned kernel after the install is done. If you run Windows or some other truthfully Adaptec supported OS look for a few *good* DPT or Adaptec controllers on eBay when the swap-out is all over."

It really depends on what you're doing...

[Sxooter]

While I'll agree that SCSI is superior for most applications, IDE is no slouch nowadays.

On one of our production servers we have twin 18 Gig 10krpm Ultrawide SCSI drives for the database, and a pai rof 80 Gig IDE drives for the static data like web content.

The pair of U2W SCSI drives in a RAID1 can be read at about 48 Megs a second by bonnie, while the pair of 80 gig IDEs can be read at about 28 Megs a second.

pgbench, a little benchmarking program for postgresql, gets about 150 to 200 transactions per second on the dual SCSI drives, while it gets about 100 to 120 on the dual IDE drives.

the problem is, even under it's heaviest loads, that machine never handles more than 10 or 20 transactions every second. Both sets of drives are plenty fast enough to hand the load.

For servers that need hundreds of gigabytes of storage but only have to provide static storage for a medium, to small group, the money you'd spend on SCSI is probably better spent on other options for that server.

For a database server handling hundreds of concurrent users, SCSI (via electrical cables) is a good choice, but maybe a SCSI over FC-AL setup would be needed.

Engineering isn't about which component is the absolute best, it's about which component makes the most sense for what you're doing.