kos-mos is dead, meet t-elos

The old file server was a beast. 2 2.4GHz dual-core Opterons, the old 90nm chips. 5GB (don’t ask) of RAM. And…2.7TB of storage, with a big pile of 250GB and 500GB drives mashed together into several arrays that were dumped into a volume group. The whole thing was encrypted just for kicks. There was also an Nvidia 7800GT board hooked up to two wide-screen displays, a PCHDTV card, a USB hub…

All told, it consumed 280W of power at idle. That’s with the CPUs sitting at 1GHz each, video card in low-power mode, etc. Was it fast? Very. But I never really got around to using the machine as intended since it had to stay up all the time: it’s a file server. The torrents run on it, mp3s stream off it, videos and data are there, etc. The idea was to use it as a fileserver, and with the leftover capacity — which, let’s be honest, there is way too much — would be used to drive a 3-display Flightgear setup. The stable release of Debian is great for a fileserver. Not so much if you want to run the latest iteration of a game under heavy development. Inevitably, dependencies crop up which are not available in stable. So that never got off the ground (see what I did there?) and it was just sucking down a lot of power for no real reason.

I replaced it….with this.

Nanbara the K6-2 webserver with t-elos, kos-mos' replacement

It’s a Sun Blade 100 with 1GB of RAM and the drive cage from kos-mos sitting atop it. It’s ugly but well thought out. It uses 90W of power, and that’s with 3 2TB drives, 2 250GB drives used to back up things, and the little 20GB IDE drives the system boots off of. With the CPU at 500MHz, it’s not going to break any speed records. The important thing was that it have ECC memory (it does), and is fast enough to stream over the wireless setup I have at full speed (it is) while using as little power as possible. It runs Debian, naturally, and aside from a few issues using the onboard sungem NIC — replaced with a generic rtl8139 board — it has been issue free under quite heavy loads. All the PCI slots are full, there are two SATA cards and the NIC installed.

This system is just fast enough. There are two easily reachable limits: the PCI bus, which is 33MHz and 32-bits wide only; and the CPU’s capacity to Do Stuff. The bus, with my configuration, seems to tap out at a bit shy of 25MB/sec of actual throughput, roughly judged by watching the speed of the RAID-1 resync on the two 250GB drives. At the same time, the RAID-5 XOR operations pretty much max out the CPU at about 20-ishMB/sec (missing the SSE/MMX optimized routines here!). Throw in software and hardware interrupts and additional traffic from the NIC…and it’s just right. It handles multiple download streams, torrents, aMule, etc without a hiccup. It stays responsive when the arrays are doing monthly parity checks. It streams HD video with all this going on. But a gigabit NIC would be pointless, as would a SATA-II controller — I tried the latter and observed identical performance to the old SATA-I cards. The additional overhead from encryption was also out of the question, but that’s fine…it was more of a ‘because I can’ thing with kos-mos. It’s not a laptop.

So here’s to hopefully years of faithful service, and thanks to the Debian team for such a solid SPARC port! And the eventual creation of the Flightgear box…

March 7, 2011 · agw · No Comments
Tags: , ,  · Posted in: Debian, Linux

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