performance

Computer latency: 1977-2017 alvin February 10, 2019 - 6:24pm

A friend sent me this link about computer latency.

A note about Scala/Java startup time alvin January 15, 2019 - 4:04pm

I was reading this post by Martin Odersky (Make the Scala runtime independent of the standard library) and came across this comment by Li Haoyi: “This would also make it more feasible to use Scala for tiny bootstrap scripts; current Mill’s launcher is written in Java because the added classloading needed to use scala.Predef (even just println) easily adds a 200-400ms of initialization overhead.” I haven’t written anything where the startup time of a Scala application was a huge problem, but that was interesting to read.

(Though I should say that I wish all Scala/Java command-line apps started faster. It’s one reason I occasionally think about using Haskell for small scripts, so I can compile them to an executable.)

Processing large files in Java alvin January 13, 2019 - 10:37am

I haven’t read the article I’ve linked to yet, I’m just saving it here for future reading.

Great tech review of Apple’s iPad A12X system

Kudos to Samuel Axon of Ars Technica for writing a very good tech review of the hardware behind Apple’s new iPad Pro (2018). As I was reading it, it reminded me of the old style of solid writing that I used to get when I bought print copies of magazines.

One of the nuggets of the article is shown in the image I’ve attached here, where you can see that the 2018 iPad Pro is faster than every MacBook Pro in existence other than its 2018 model, at least in terms of the Geekbench multi-core performance tests. If you dig through the images in the article you’ll see that the story isn’t quite as powerful in the single-core benchmark, where the iPad Pro lags the 2018 MacBook Pro by up to 16%. But in those tests the iPad Pro is roughly the equivalent of a 2018 Dell XPS 15 2-in-1 model. (The older Macs use Intel Core i7 and Xeon W processors, and the Dell model uses an Intel Core i7. The 2018 MacBook Pro uses an Intel Core i9.)

These numbers — comparing a tablet to i7 and i9 processors — make one think that Apple will be using their own chips inside Mac computer systems some time soon.

JMH, an SBT plugin for running OpenJDK JMH benchmarks

JMH is an SBT plugin for running OpenJDK JMH benchmarks. Per its docs, “JMH is a Java harness for building, running, and analysing nano/micro/milli/macro benchmarks written in Java and other languages targeting the JVM.”

They also recommend reading an article titled Nanotrusting the Nanotime if you’re interested in writing your own benchmark tests.

How to speed up Scala compilation times with scalac-profiling alvin June 5, 2018 - 11:49am

scala-lang.org has an article titled Speeding Up Compilation Time with `scalac-profiling` where they demonstrate how they reduced a project’s compilation time from 32.5 seconds down to 4 seconds. In addition to all of the scalac and profiling details, it demonstrates a nice use of flamegraphs.

Scala 2.12.5 compiler flag to let the backend run in parallel alvin May 14, 2018 - 6:19pm

I haven’t tried it yet, but as a note to self, Scala 2.12.5 introduced a new -Ybackend-parallelism N compiler flag with which “the backend can now run in parallel on N threads.”

Drupal 8 anti-spam modules, caching, and performance alvin April 17, 2018 - 7:39pm

I’m not sure why, but on April 3, 2018, the people behind the Mollom anti-spam module for Drupal basically went out of business. This meant that I either had to disable comments on this site (which I did for a while), or look at other anti-spam modules, which I did over the weekend.