From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bob Drzyzgula Date: Sun, 12 Jul 1998 23:59:53 +0000 Subject: Re: Ultra AXmp Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ultralinux@vger.kernel.org OK, so now this is really interesting. I had no idea that my mail would solicit this kind of response, especially with a complete lack of any attempt to answer the actual question (i.e. what will this thing do under Linux). But since y'all raise the point, I think it might be well to examine it a little. I'm curious about the accuracy of the assertion that the AXmp is overpriced compared to commodity x86 hardware. First of all, vis-a-vis the AXmp, Is there any "commodity" hardware? There's the Goliath, and by the end of the year there should be some 450NX boards around, but... commodity? A Goliath-based configuration with top-end Pros should easily run into five digits, hardly chicken feed. If you don't want to build one yourself, there's always Compaq, HP, ALR, etc., but Sun has nothing on those guys as far as price is concerned... Price out a decently-configured 4-way ProLiant 7000 with 200MHz Pros each at 1MB cache, and I think that you'll find that it ain't pocket change. So what hardware, advertised in Computer Shopper or whatever, would you compare the AXmp to and find that the AXmp is way overpriced? If you want to compare to, say, four uniprocessor or two dual-processor systems, I'd say that would be a apples-and-oranges thing, and you'd probably want to compare to the AXi, which sells for around $1800, motherboard and processor together, has dual-channel Symbios SCSI, 10/100 Ethernet and two independant PCI busses, three slots on each. You can easily build an 300MHz AXi-based system with a half-gig of memory for under $5,000, showing SPEC95 ratings in the mid-to-upper teens. But back to the AXmp, it was dissed somewhat on the basis of I/O, which I don't understand. The AXmp has four PCI busses -- two sets of two, each set bridged into a 72-bit crossbar channel; each set has a 66MHz bus and a 33MHz bus. The memory bus operates at 576 bits wide into the crossbar, and each of two UPA processor complexes pipe in at 144bits wide and 120MHz with the 360MHz processors. The board costs around $6000, the 300MHz processors around $2200 each, and the memory is standard 168-pin DIMMs. Xeon processors are in the same price range as the UltraSPARC II processors, and, although the Xeon does better on integer and the SPARC better on floating point, the sum of SPECfp95 and SPECint95 for a 400MHz Xeon is almost exactly the same as that for a 300MHz UltraSPARC II. I can believe that a 450NX motherboard will cost less than the AXmp (something that remains to be seen), but I don't see the I/O capacity in the 450NX PCIset that I see in the Sun Crossbar switch. As far as what you hang off the back in the way of RAID devices, it seems to me that the situation is largely the same between a 450NX system and an AXmp. The AXmp uses the 53C876 and the SC450NX, for example (which looks, I must say, like a *very* nice platform) uses a 53C896 and a 53C810AE. But the AXmp has more PCI bandwidth than the SC450NX. When I need a back end disk device, I ususally use the Kingston DS-500 9-bay rackmount fully decked out with dual power supplies, DE-100 SCA hot-swap carriers & frames, a CMD CRD-5440 SCSI-to-SCSI controller and a 6V lead-acid battery. Lately we've been populating them with the Fujitsu MAB3091-SC 9.1 GB drives, which work well with the CMD, run cool and of which I bought a big batch recently for $640 each. A 4U rack-mount enclosure with 45GB of disk in a RAID 5 setup (5 data, 1 parity, 1 hot spare, 1 warm spare) runs somewhere around $10K in aggregate. You can put this thing on the back of just about anything you want... Pentium, Xeon, AXmp, UltraEnterprise 6000, Alpha, whatever. [And BTW, I'm looking at the AXmp not for file servers but for compute servers, so I could care less about the back-end disk. This is more of a Beowulf kind of situation, and wondering about UltraPenguin on the AXmp is related to this. I've got users who burn up machines for months straight doing stochastic simulations and monte-carlo models. In these cases, all I care about are local CPU-memory bandwidth and floating point performance, and the SPARC machines still beat the pants off an x86 for this; and yes, an Alpha or a PowerPC could probably do better, but we've been a Sun shop since 1985 and other RISC architectures are a hard sell...] As far as maintenance and support, I generally take as little as possible. Sun's bronze contracts aren't that much, and you always have the option of buying spare parts yourself. We mostly use Solaris on our SPARC systems, but if UltraPenguin became a viable option for the AXmp, then the Solaris support issue would largely go away when the application allows it. (Although Sun still makes you buy a Solaris RTU for the SME motherboards). So, yean, the UltraEnterprise GigaPlane stuff is outrageously priced. The 450 is still up there although not quite as bad. And yeah, you can build a decent dual-processor x86 server for $2K (and that's what I do for NT print servers, for example...), but when you get into the quad-processor range, the AXmp seems to me to be one of the most cost-competitive things that Sun has done in a long time. Please tell me how I'm wrong about this... --Bob -- ============================== Bob Drzyzgula It's not a problem bob@drzyzgula.org until something bad happens ==============================