DTrace at Home

I had been procrastinating making the family holiday card. It was a combination of having a lot on my plate and dreading the formulation of our annual note recapping the year; there were some great moments, but I’m glad I don’t have to do 2016 again. It was just before midnight and either I’d make [...]

Posted on December 17, 2016 at 9:32 pm by ahl · Permalink · Comments Closed
In: DTrace

Submitting to Systems We Love

We’ve been overwhelmed by the positive response to Systems We Love! As simple as this concept is, Systems We Love — like Papers We Love, !!Con and others that inspired it — has tapped into a current of enthusiasm. Adam Leventhal captured this zeitgeist in a Hacker News comment: What catches our collective attention are [...]

Posted on September 30, 2016 at 2:57 pm by bmc · Permalink · Comments Closed
In: Uncategorized

Systems We Love

One of the exciting trends of the past few years is the emergence of Papers We Love. I have long been an advocate of journal clubs, but I have also found that discussion groups can stagnate when confined to a fixed group or a single domain; by broadening the participants and encouraging presenters to select [...]

Posted on September 26, 2016 at 2:55 pm by bmc · Permalink · Comments Closed
In: Uncategorized

Turtles on the Wire: Understanding how the OS uses the Modern NIC

The modern networking card (NIC) has evolved quite a bit from the simple Ethernet cards of yesteryear. As such, the way that the operating system uses them has had to evolve in tandem. Gone are the simple 10 Mbit/s copper or (BNC) devices. Instead, 1 Gb/s is common-place in the home, 10 Gb/s rules the [...]

Posted on September 15, 2016 at 10:06 am by rm · Permalink · Comments Closed
In: Miscellaneous

Hacked by a bug?

Early this afternoon, I had just recorded a wide-ranging episode of Arrested DevOps with the incomparable Bridget Kromhout and noticed that I had a flurry of Twitter mentions, all in reaction to this tweet of mine. There was just one problem: I didn’t tweet it. With my account obviously hacked, I went into fight-or-flight mode [...]

Posted on September 13, 2016 at 12:11 am by bmc · Permalink · Comments Closed
In: Uncategorized

TCP puzzlers

This post was cross-posted to the Joyent blog. It’s been said that we don’t really understand a system until we understand how it fails. Despite having written a (toy) TCP implementation in college and then working for several years in industry, I’m continuing to learn more deeply how TCP works — and how it fails. [...]

Posted on August 18, 2016 at 9:02 am by dap · Permalink · Comments Closed
In: Uncategorized

A Filesystem on Noms

Since Noms dropped last week the dev community has seemed into it. “Git for data” — it simultaneously evokes something very familiar and yet unconstrained. Something that hasn’t been well-noted is how much care the team has taken to make Noms fun to build with, and it is. Noms is a content-addressable, decentralized, append-only database. It borrows [...]

Posted on August 9, 2016 at 8:54 am by ahl · Permalink · Comments Closed
In: APFS, btrfs, FUSE, go, noms, software, ZFS

I Love Go; I Hate Go

I liked Go right away. It was close enough to C and Java to be instantly familiar, the examples and tutorials were straightforward, and I was quickly writing real code. I’ve wanted to learn Go since its popularity was surging few years ago. In no danger of being judged an early adopter, I happily found [...]

Posted on August 1, 2016 at 8:19 pm by ahl · Permalink · Comments Closed
In: software

dtrace.conf(16) wrap-up

Something that got a little lost in the excitement of Samsung’s recent acquisition of Joyent was dtrace.conf(16), our quadrennial (!) unconference on DTrace. The videos are up, and in the spirit of Adam Leventhal‘s excellent wrap-ups from dtrace.conf(08) and dtrace.conf(12), I wanted to provide a survey of the one-day conference and its content. Once again, [...]

Posted on July 29, 2016 at 12:00 pm by bmc · Permalink · Comments Closed
In: Uncategorized

APFS in Detail: Conclusions

This series of posts covers APFS, Apple’s new filesystem announced at WWDC 2016. See the first post for the table of contents. Summing Up I’m not sure Apple absolutely had to replace HFS+, but likely they had passed an inflection point where continuing to maintain and evolve the 30+ year old software was more expensive than building [...]

Posted on June 19, 2016 at 12:37 pm by ahl · Permalink · Comments Closed
In: APFS, software