Random ramblings

Wednesday December 07, 2005

Niagara

Some lovely hardware announced yesterday. Suns' CoolThreads servers, the T1000 and T2000. Richard McDougall has some information and a comprehensive roundup of links to T1 blogs.

Highlights of Niagara (AIUI, hopefully someone correct me if I've made a mistake):

• Up to 8 single-issue, in-order UltraSPARC cores. Each core is 4-way threaded. Single cycle thread switches (no gigantic pipelines to flush, as per a certain other commodity threaded CPU).
• Huge, nay, staggering amount of memory bandwidth. 4 on-chip DDR2 controllers, 25GB/s potential peak bandwidth. The current systems have 20GB/s peak. Awesome.
• Astronomical inter-core bandwidth, somewhere in the order of 78GB/s to 134GB/s through an on-chip crossbar (I can't find the blog back with the details on this right now unfortunately).
• Single shared FPU on T1. As someone on /. pointed out, you're not going to want to run Quake4 on this machine, at least not the graphical client. However the Quake server, if it isn't too FPU heavy, might well be amazing on this chip. The architecture could have more FPU units added in the future conceivably, if there is a need (FPU heavy applications probably do not tend to have much of a need for many execution threads).
• On-chip crypto engine. So, despite the previous point, the T1 still easily beats dual 3.6GHz Xeons for RSA decrypts, and absolutely crushes it to dust for RSA sign/s.
• Hypervisor support. T1 can virtualise itself and run multiple SPARC operating systems. You will in time be able to run multiple operating systems on Niagara, e.g. multiple copies of Solaris, maybe even a few Linux and/or FreeBSD instances (yes, Sun would welcome other OSes to support Niagara).
• T1 design to be opensourced. E&E Eng classes and projects are going to be a lot more fun! This is quite an amazing move really, the hardware guys must have been jealous of all the open-sourcing over in software.
• Last but definitely not least: really low power requirements. Probably the first server class CPU to offer significantly more performance for less power. The T2000 is based on the X4200 case - the designers had downspec the 540W PSUs which it has for Opteron, to a 400W for better PSU efficiency because they could not get the T2000 to draw more than 350W, even with it fully-loaded (32GB of DDR2 RAM, PCI cards, etc.). Less heavily-laden configurations will draw significantly less than 350W.

Significantly higher transaction / client-server performance for far lower power requirements than comparable traditional servers = many fold increase in performance/watt. Such many fold increases are very very rare in processor evolution. Possibly the last time this was seen was when SPARC and MIPS showed that the RISC philosophy of less == more could trounce comparable technology CISC chips of the day or (to a lesser extent) when DEC proved that a painstakingly hand-tuned design could fly[1]. Niagara does the same thing again, stripping down the resistor count in certain CPU functionality and using them far more productively in other areas, just as RISC did two decades ago[2].

I can't wait to get a chance to play with one. The T1000 and T2000 would make for really nice BGP route-servers, at least if we divide up bgpd into multiple processes, and crypto-engine would be extremely useful if/when Secure BGP (in whatever form) comes along.

1. And, apparently, really really hard to move to new processes too - unfortunately for DEC and AXP.

2. RISC did triumph in the performance space. Even modern "CISC" processors (ie x86) are RISC at heart (e.g. compare K7 and Opteron with the Alpha 21264), maybe they'd be better described as "CRISC".

Thursday November 03, 2005

Cerncourier article on data centre power usage

Interesting article on data centre power usage in the CERN Courier, from the perspective of Google. Apparently they've even managed to convince board makers to cut out redundant DC inputs.

( Nov 03 2005, 07:54:41 AM GMT ) Permalink Comments [0]

Wednesday September 07, 2005

How to take GRUB screenshots

Someone asked google "how to take grub screenshot" and arrived at my blog. The answer is QEMU, a portable and quite fast JIT emulator of computer architectures, most notably Intel i386, but also PPC, MIPS, Alpha, etc.. Runs on Solaris, Linux, Windows, OS X and the various BSDs. The i386 system emulator will run just about any i386 OS which runs happily on older Pentium era PCs (roughly the class of system, in terms of hardware devices, which it emulates), including Solaris 10. Solaris NV newboot will not run though as it requires ACPI, which QEMU does not provide (it will run newboot GRUB though, and boot the kernel, which was all I needed to get the screen shot of Solaris newboot's GRUB menu ).

( Sep 07 2005, 12:11:23 AM IST ) Permalink Comments [0]

Saturday August 13, 2005

another blog "quiz" meme

So useless, yet still so impossible to not display a high score on your blog..

Monday January 31, 2005

Quagga 0.98.1

Quagga 0.98.1 has been released. The CVS changelog tells the full story, but essentially it boils down to fixing two silly bugs which had gotten into the .0 release. One affecting ospfd where MD5 auth was enabled and one causing bgpd to needlessly resend UPDATEs every scan interval and induce needless load. Additionally there's a working fix for an odd ospfd crash, the true origin of which has not been nailed, but its symptom has been dealt with.

The signs so far are that 0.98.1 is a good yin. yay!

Monday January 17, 2005

Another blog meme

[Update]: Retest, picking equivalently nerdly answers for questions where no answer fits me (eg calculator doesnt have a "bc + gnuplot" option, so I chose HP RPN on retest):

Friday December 31, 2004

travels

I have Europe covered, now just need to visit South America, Africa, Asia and Australasia.

create your own visited countries map