Caffeine cache adopts Window TinyLfu eviction policy
‘Caffeine is a Java 8 rewrite of Guava’s cache. In this version we focused on improving the hit rate by evaluating alternatives to the classic least-recenty-used (LRU) eviction policy. In collaboration with researchers at Israel’s Technion, we developed a new algorithm that matches or exceeds the hit rate of the best alternatives (ARC, LIRS). A paper of our work is being prepared for publication.’ Specifically:
W-TinyLfu uses a small admission LRU that evicts to a large Segmented LRU if accepted by the TinyLfu admission policy. TinyLfu relies on a frequency sketch to probabilistically estimate the historic usage of an entry. The window allows the policy to have a high hit rate when entries exhibit a high temporal / low frequency access pattern which would otherwise be rejected. The configuration enables the cache to estimate the frequency and recency of an entry with low overhead. This implementation uses a 4-bit CountMinSketch, growing at 8 bytes per cache entry to be accurate. Unlike ARC and LIRS, this policy does not retain non-resident keys.
(tags: tinylfu caches caching cache-eviction java8 guava caffeine lru count-min sketching algorithms)
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The ever-shitty Java serialization creates a security hole
(tags: java serialization security exploits jenkins)
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Danish glassware artist making wonderful Wunderkammers — cabinets of curiosities — entirely from glass. Seeing as one of his works sold for UKP50,000 last year, I suspect these are a bit out of my league, sadly
(tags: art glassware steffen-dam wunderkammers museums)
London garden bridge users to have mobile phone signals tracked
If it goes ahead, people’s progress across the structure would be tracked by monitors detecting the Wi-Fi signals from their phones, which show up the device’s Mac address, or unique identifying code. The Garden Bridge Trust says it will not store any of this data and is only tracking phones to count numbers and prevent overcrowding.
(tags: london surveillance mobile-phones mac-trackers tracking)
Red lines and no-go zones – the coming surveillance debate
The Anderson Report to the House of Lords in the UK on RIPA introduces a concept of a “red line”:
“Firm limits must also be written into the law: not merely safeguards, but red lines that may not be crossed.” … “Some might find comfort in a world in which our every interaction and movement could be recorded, viewed in real time and indefinitely retained for possible future use by the authorities. Crime fighting, security, safety or public health justifications are never hard to find.” [13.19] The Report then gives examples, such as a perpetual video feed from every room in every house, the police undertaking to view the record only on receipt of a complaint; blanket drone-based surveillance; licensed service providers, required as a condition of the licence to retain within the jurisdiction a complete plain-text version of every communication to be made available to the authorities on request; a constant data feed from vehicles, domestic appliances and health-monitoring personal devices; fitting of facial recognition software to every CCTV camera and the insertion of a location-tracking chip under every individual’s skin. It goes on: “The impact of such powers on the innocent could be mitigated by the usual apparatus of safeguards, regulators and Codes of Practice. But a country constructed on such a basis would surely be intolerable to many of its inhabitants. A state that enjoyed all those powers would be truly totalitarian, even if the authorities had the best interests of its people at heart.” [13.20] … “The crucial objection is that of principle. Such a society would have gone beyond Bentham’s Panopticon (whose inmates did not know they were being watched) into a world where constant surveillance was a certainty and quiescence the inevitable result. There must surely come a point (though it comes at different places for different people) where the escalation of intrusive powers becomes too high a price to pay for a safer and more law abiding environment.” [13.21]
(tags: panopticon jeremy-bentham law uk dripa ripa surveillance spying police drones facial-recognition future tracking cctv crime)
Dublin is a medium-density city
Comparable to Copenhagen or Amsterdam, albeit without sufficient cycling/public-transport infrastructural investment
(tags: infrastructure density housing dublin ireland cities travel commuting cycling)