toricls

Lima (Linux virtual machines, on macOS) installation guide for M1 Mac.

Sep. 27th 2021 UPDATED

Now we can install patched version of QEMU via Homebrew (thank you everyone for the info!). Here is the updated instruction with it:

Used M1 Mac mini 2020 with macOS Big Sur Version 11.6.

1. Install QEMU & Lima

adrian-baker

public AWSCredentialsProvider getDefaultCredentials() {

    final String profileName = AwsProfileNameLoader.INSTANCE.loadProfileName();
    final AllProfiles allProfiles = new AllProfiles(Stream.concat(
            BasicProfileConfigLoader.INSTANCE.loadProfiles(
                    AwsProfileFileLocationProvider.DEFAULT_CONFIG_LOCATION_PROVIDER.getLocation()).getProfiles().values().stream(),
            BasicProfileConfigLoader.INSTANCE.loadProfiles(
                    AwsProfileFileLocationProvider.DEFAULT_CREDENTIALS_LOCATION_PROVIDER.getLocation()).getProfiles().values().stream())
            .map(profile -> new BasicProfile(profile.getProfileName().replaceFirst("^profile ", ""), profile.getProperties()))
            .collect(Collectors.toMap(profile -> profile.getProfileName(), profile -> profile,

frsyuki

Performance degradation due to too many active tasks

When we ran a stress testing tool on Digdag server, the server stopped running tasks. The cause was that propagateAllPlannedToDone and propagateBlockedChildrenToReady methods of io.digdag.core.workflow.WorkflowExecutor class were too slow when there're too many active tasks.

Here is the scenario:

1. Many workflows submit many tasks.

2. Eventually, there're a lot of tasks in PLANNED or BLOCKED tasks.

gakuzzzz

あなたの sbt update を爆速にする sbt-coursier の紹介

この記事は Scala Advent Calendar 2016(Adventar) 10日目の記事です。

今は 12/10 の 625時です。年明けなんて無かった。いいね？

さてさて、sbt の依存jarのダウンロードが遅い、というのは割とよく言われる事であります。

で、この原因の一旦に、sbtが Apache Ivy を使っている、という点があります。

hiroyuki-sato

git clone https://github.com/civitaspo/embulk-output-hdfs.git
cd embulk-output-hdfs
./gradlew gem
cd pkg
embulk gem install -l embulk-output-hdfs-0.1.0.gem

gakuzzzz

UserId などの型はどうするべきか

1. primitive 型をそのまま使う

case class Person(id: Long, name: String, organizationId: Long)
object Person {

  def groupByOrg: Map[Long, Seq[Person]] = ...

svrc-personal

Summary of Behaviour:

A.   OpenJDK 7 b65.  

1.   Default in java.security is securerandom.source=/dev/urandom   
2.   If securerandom.source=/dev/urandom, NativePRNG is used, SecureRandom.nextBytes() is non-blocking via /dev/urandom ; SecureRandom.generateSeed(x) is blocking via /dev/random
3.   if securerandom.source=/dev/random, then SHA1PRNG is used.  Initial seed is blocking via /dev/random.   No other accesses.
4.   If securerandom.source=/dev/./urandom then SHA1PRNG is used.  Initial seed is non-blocking via /dev/./urandom.  No other accesses.

B.   Oracle JDK 8 b25.  

ueshin

SparkSQL samples for ScalaMatsuri2014

Initialize

Docker

https://github.com/ueshin/docker

$ docker run -it -p 14040:4040 spark:1.1.0-rc4

hofmannsven

MySQL

Getting started

• http://www.sqlteaching.com/
• https://www.codecademy.com/learn/learn-sql
• https://www.codecademy.com/catalog/language/sql

Related tutorials

• MySQL-CLI
• Analyzing Business Metrics

rxin

/**
 * To compile:
 *  scalac -optimize ByteBufferPerf.scala
 *
 * JAVA_OPTS="-Xmx2g" scala IntArrayPerf 10
 *  49  62  48  45  48  45  48  50  47  45
 *
 * JAVA_OPTS="-Xmx2g" scala ByteBufferPerf 10
 *  479 491 484 480 484 481 477 477 472 473