sslotin

#pragma GCC optimize("Ofast")
#pragma GCC target("avx2,fma")

#include <bits/stdc++.h>
#include <x86intrin.h>

const int u = 48; // all block coordinates must be a multiple of lcm(6, 16) = 48

const int n = 20 * u; // = 1920 (also try 240, 480, 960)
alignas(64) float a[n * n], b[n * n], c[n * n];

rygorous

why doesn't radfft support AVX on PC?

So there's two separate issues here: using instructions added in AVX and using 256-bit wide vectors. The former turns out to be much easier than the latter for our use case.

Problem number 1 was that you positively need to put AVX code in a separate file with different compiler settings (/arch:AVX for VC++, -mavx for GCC/Clang) that make all SSE code emitted also use VEX encoding, and at the time radfft was written there was no way in CDep to set compiler flags for just one file, just for the overall build.

[There's the GCC "target" annotations on individual funcs, which in principle fix this, but I ran into nasty problems with this for several compiler versions, and VC++ has no equivalent, so we're not currently using that and just sticking with different compilation units.]

The other issue is to do with CPU power management.

fogus

# books that helped form MY thinking about technology/programming/systems


## more so

Architecture of Symbolic Computers by Kogge
Art of the Metaobject Protocol by Kiczales, et al.
Bootstrapping by Thierry Bardini
Commodore 64 users guide
Computer Lib / Dream Machines by Ted Nelson

jdegoes

Applied Functional Programming with Scala - Notes

Copyright © 2016-2018 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

pervognsen

enum { BMAX = 32, BMIN = BMAX / 2, BHEIGHT = 6 };

struct BNode {
    uint32_t length;
    Key keys[BMAX];
    union {
        BNode *children[BMAX];
        Value values[BMAX];
    };
};

danidiaz

A series of reading lists mostly related to functional programming.

ocharles

{-# LANGUAGE GeneralizedNewtypeDeriving #-}

import Control.Monad.IO.Class
import Control.Monad.Trans.Class
import Prelude hiding (log)

--------------------------------------------------------------------------------
-- The API for cloud files.
class Monad m => MonadCloud m where
  saveFile :: Path -> Bytes -> m ()

patshaughnessy

This note explains how to build Postgres from source and setup to debug it using LLDB on a Mac. I used this technique to research this article:
http://patshaughnessy.net/2014/10/13/following-a-select-statement-through-postgres-internals

1. Shut down existing postgres if necessary - you don’t want to mess up your existing DB or work :)

$ ps aux | grep postgres
pat               456   0.0  0.0  2503812    828   ??  Ss   Sun10AM   0:11.59 postgres: stats collector process       
pat               455   0.0  0.0  2649692   2536   ??  Ss   Sun10AM   0:05.00 postgres: autovacuum launcher process       
pat               454   0.0  0.0  2640476    304   ??  Ss   Sun10AM   0:00.74 postgres: wal writer process       
pat               453   0.0  0.0  2640476    336   ??  Ss   Sun10AM   0:00.76 postgres: writer process       

prakhar1989

Rich Hickey on becoming a better developer

Rich Hickey • 3 years ago

Sorry, I have to disagree with the entire premise here.

A wide variety of experiences might lead to well-roundedness, but not to greatness, nor even goodness. By constantly switching from one thing to another you are always reaching above your comfort zone, yes, but doing so by resetting your skill and knowledge level to zero.

Mastery comes from a combination of at least several of the following:

codeinthehole

How to share a folder with a docker container on OSX

Mounting shared folders between OSX and the docker container is tricky due to the intermediate boot2docker VM. You can't use the usual docker -v option as the docker server knows nothing about the OSX filesystem - it can only mount folders from the boot2docker filesystem. Fortunately, you can work around this using SSHFS.