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Schrödinger's Cat and RCU (Well, Structured Procrastination, Actually)
davecb writes "Paul E. McKenney, one of the Linux RCU implementors, addresses the problem of synchronization using structured deferral on, what else, Mr Schrödinger's famous cat. Courtesy of deferral/procrastination, the cat can be both alive and dead at the same time. 'In this example, Schrödinger would like to construct an in-memory database to keep track of the animals in his zoo. Births would of course result in insertions into this database, while deaths would result in deletions. The database is also queried by those interested in the health and welfare of Schrödinger's animals. Schrödinger has numerous short-lived animals such as mice, resulting in high update rates. In addition, there is a surprising level of interest in the health of Schrödinger's cat, so much so that Schrödinger sometimes wonders whether his mice are responsible for most of these queries. Regardless of their source, the database must handle the large volume of cat-related queries without suffering from excessive levels of contention. Both accesses and updates are typically quite short, involving accessing or mutating an in-memory data structure, and therefore synchronization overhead cannot be ignored.'"
I feel like this submission was generated by SCIgen.
sysadmins and parents of newborns get the same amount of sleep.
I know! Let's explain the workings of a deterministic computational system using analogies to quantum mechanics! Everyone find quantum mechanics clear and intuitive.
Slashdot Translation: It's similar to how an article exists in a superposition of both interesting and uninteresting at the same time, so long as no one reads it. Rather than RTFA and collapse the superposition, we can simply read the quantumly entangled comments to determine the degree of interest in accordance with our groupthink.
He can be both ignorant and knowledgeable at same time until measured.
And if in an entangled pair of students one just copies notes off other, measuring one of them will immediately collapse the wave function of another.
Schrödinger's whole point was that for a macroscopic system as complex as a cat to be simultaneously alive and dead was obvious nonsense, and therefore there was something still missing in our understanding of quantum mechanics.
Ironically, the outcome was people agreeing that quantum weirdness is, well, weird, but simultaneously believing he was talking about a cat actually being both alive and dead.
So probably he turning in his grave with a spin 1/2 :-)
They're going to want reports and stats not just on the current living animals. I didn't RTFA ('natch) but if they missed that requirement, what else have they overlooked?
I think what you overlooked was that the "database" in the article was just a colorful contrivance to illustrate common usages of an in-memory data structure (e.g. a page-table in the Linux kernel) and not a True Database in the SQL/web-server/generate-me-a-report sense.
I don't care if it's 90,000 hectares. That lake was not my doing.