Wednesday, July 21, 2010

An exchange by any other name

This madness was based on a conceptual fallacy. ECNs really weren't broker-dealers; instead, they were exchanges and should have been regulated accordingly. Exchanges traditionally have charged their members fees for accessing exchange trading services. Persons who are not members can only obtain access to the exchange through the facilities of members. Confusing the broker-dealer and exchange models led to unanticipated consequences.

. . . .

Eventually, this road led to Regulation NMS. To level the playing field, all regulated participants--exchanges, ATSs and broker-dealers--were permitted to charge access fees to non-customers, but the amount that could be charged was capped. Among other things, this forced the transformation of the NYSE into a huge ECN forced to compete on a level playing field with other exchanges. It also led surviving ECNs to merge with exchanges or to register as national securities exchanges.

It is a nice conceit to imagine that competition spurs innovation, lower prices and increasing social welfare. But innovation and lower prices are not the only ways to compete, and some methods of competition do not increase social welfare. The flash order is an example of competition's dark side.

What is an ATS, what is an exchange? Who gets screwed? Chaos abounds from ill thought out market structure reform, it seems.

Saturday, July 17, 2010

Know your DNS: Chaosnet and Hesiod

While everyone in their right minds uses the IN/Internet class in their DNS servers, Chaosnet (CH) and Hesiod (HS) are still supported if you want to be obscure.

Sunday, July 11, 2010

CPAN 2.0

Greatest announcement since Perl 5.12 GA.

Saturday, July 3, 2010

Status update 5

Lack of change control is maddening. I spend way too much effort fixing things that shouldn't be broken. Reference data is ill thought out. Is the New York Stock Exchange represented by the ISO standard code XNYS or NYSE or N? Is Arca represented by XPSE or ARCAX or ARCA or PCOAST or P or . . . you get the idea.

Maybe I should take a job picking nits. At least when you're done, you have a juicy pile of nits to dig into for dinner.

Non-ECC memory considered harmful

For me, bitflips due to cosmic rays are one of those problems I always assumed happen to “other people”. I also assumed that even if I saw random cosmic-ray bitflips, my computer would probably just crash, and I’d never really be able to tell the difference from some random kernel bug.

A few weeks ago, though, I encountered some bizarre behavior on my desktop, that honestly just didn’t make sense. I spent about half an hour digging to discover what had gone wrong, and eventually determined, conclusively, that my problem was a single undetected flipped bit in RAM. I can’t prove whether the problem was due to cosmic rays, bad RAM, or something else, but in any case, I hope you find this story interesting and informative.