Stuff I read last week

2017-06-05

• Converting floats to strings, part 1 Float printing with decimal bignums instead of binary bignums.
• The fear of dart:mirrors On the reflection API in Dart, using JSON parsing as the motivating example. The interesting takeaway is that unlimited reflection is a huge problem for compiling Dart to JS, rather than executing it natively. (There's often value in more limited interfaces for doing dynamic operations, just since they're easier to analyze).
• Experiments with prepledge On the difficulty of applying syscall level sandboxing (OpenBSD pledge, in this case) to arbitrary application binaries, rather than programs explicitly designed to be sandboxed.
• Jenga: Sotware-Defined Cache Hierarchies Reconfigurable L3/L4 caches. The suggestion is that applications have such different requirements for the types and sizes of lower level caches (or even having them at all). So partition a multicore system into several virtual systems, each having a static allocation of cores and sram/stacked dram cache. The OS will monitor the system behavior, and reconfigure the partitioning as needed.
• Mosaic: processing a trillion-edge graph on a single machine Terabytes of NVMe storage, 4 Xeon Phis (so 244 cores/976 hardware threads) and a Hilbert curve-style data layout to get good data locality.
• Writing a Really, Really Fast JSON Parser Micro-optimizations for string processing.
• Building the Level Design of a procedurally generated Metroidvania Procedural level generation for a 2d combat platformer. Maybe the most interesting bit here is generating maps with very different topology for the different "biomes".

  Also. I've been playing way too much Dead Cells this weekend, it's pretty good. Not really a Metroidvania though, despite what the title of this blog post says.