bitminer

It is a useful paper, yes. Good examples, good diagnosis of issues in systems theory, good definition of a way forward.

However it suffers from (a) weak definitions and (b) implausible or strange descriptions.

For (a), what is a "strong feedback loop"? Does it have high gain (low error) or high bandwidth (fast)? Is it hidden (the accidental link imbalance example)? Is it obvious (the cold cache example)? What makes it "strong"?

Or, conversely, what is a "weak" feedback loop?

A number of acronyms are undefined (SRE, LIFO). I think I know what they mean, and most HN readers will too. What about the other readers?

And using Wikipedia to define metastability? There must be a more persistent or academically defendable reference. Wikipedia is OK for informal definitions. In a paper calling for more academic studies this is ironic.

(b) Section 2.1 "When replicas are sharded differently..." Huh?

Section 4 "upper bound" used as a verb. Should be "limit or place bounds on".

Section 4 "The strength of the loop depends on a host of constant factors from the environment..." Odd, the term is not defined but this is the second dependency listed. Very strange.

In short it needs/needed a better reviewer.

That all said, it has summarized a lot of good ideas on controlling stability in distributed systems.

Other references may be found in Adrian Colyer's "the morning paper". No longer updated but has many years of good references. See blog.acolyer.org.

Especially since Netflix has a lot of entertainment featuring black actors, producers etc. from the US. And a lot of Nigerian and South African productions too.

You just have to look for it.

Be very aware -- SSD must be plugged in otherwise they may lose data after a few years.

The time varies with temperature. Search for SSD data retention for more info.

The JEDEC standard is the one to read.

21.7 cents per pixel.

Stock photos cost $5 to $100 and come with distribution rights.

Somebody paid a lot of money for bragging rights.

Non rapid updates to HN profile, I guess.

hncollector@ and the domain is bitminer.ca

I have a demo website that is "4-clicks" to ordering satellite imagery. Include one for the data type, and one for the date.

Contact me by email if you would like a demo. (I'm trying to avoid HN overload.)

There is also the CREDO app, check the Google Android app store.

And the New York Times article might be true.

I'm sure that Solarwinds uses many more developer tools than what Jetbrains supplies. But only Jetbrains was "founded by Russians" so the NYT leads with that.

Question: did you unmount/mount the source filesystem between tests? When the size of data is less than RAM you are measuring cache speed, not so much disk speed. (And yes I realize that you have SSDs.)

>>[The] defenses include obvious technical components (e.g. backup systems, ‘safety’ features of equipment) and human components (e.g. training, knowledge) but also a variety of organizational, institutional, and regulatory defenses (e.g. policies and procedures, certification, work rules, team training).

This omits "design" for defenses against problems.

Example: the chemical industries in many countries in the 1960s had horrendous accident records: many employees were dying on the job. (For many reasons) the owners re-engineered their plants to substantially reduce overall accident rates. "Days since a lost-time accident" became a key performance indicator.

A key engineering process was introduced: HAZOP. The chemical flows were evaluated under all conditions: full-on, full-stop, and any other situations contrary to the design. Hazards from equipment failures or operational mistakes are thus identified and the design is adjusted to mitigate them. This was s.o.p. in the 1980s. See Wikipedia for an intro.

Similar approaches could help IT and other systems.

I remember pestering my father for one back in 1973.

He managed to get a demonstrator from the local office of HP, for iirc CAD$695, which was a lot of money in those days.

I would push a few number keys and the log button, and, like magic, 10 significant figures. Beyond magic.

The other mystery was this: on the label at the bottom on the reverse side, it said "Made in Singapore".

To me, in the early 1970s Canada, that was as mysterious a place as you could imagine.

(I'm sure it was assembled there, not manufactured, but still.)