scalability.org

Data loss, thanks to buggy driver or hardware

2019-02-062019-02-06 by joe

So this happened on the 3rd, on one of my systems Feb 3 03:02:39 calculon kernel: [195271.041118] INFO: task kworker/20:2:757 blocked for more than 120 seconds. Feb 3 03:02:39 calculon kernel: [195271.048116] Not tainted 4.20.6.nlytiq #1 Feb 3 03:02:39 calculon kernel: [195271.052678] “echo 0 > /proc/sys/kernel/hung_task_timeout_secs” disables this message. Feb 3 03:02:39 calculon kernel: [195271.060626] … Read moreData loss, thanks to buggy driver or hardware

Interesting articles on systemd and ZFS

2019-01-282019-01-28 by joe

The systemd article is on LWN, and discusses the “tragedy” of it. The ZFS post was linked from HackerNews and discusses risk to ZFS’s future from the perspective of FreeBSD leveraging ZFS on Linux as its upstream. Ok, first onto systemd. For those who don’t know systemd, think of it as the borg that ate … Read moreInteresting articles on systemd and ZFS

Reflections on where we’ve been in HPC, and thoughts on where we are going

2019-01-202019-01-20 by joe

Looking back on past reviews from 2013 and a few other posts, and what has changed since then up to 2019 (its early, I know), I am struck by a particular thought I’ve expressed for decades now. In 2009 I wrote HPC has been moving relentlessly downmarket. Each wave of its motion has a destructive … Read moreReflections on where we’ve been in HPC, and thoughts on where we are going

Systems that are designed to fail, often do

2018-12-182018-12-18 by joe

I’ve been saying this for mumble decades. What I mean by “designed to fail” isn’t specifically that someone wants a system to fail. Rather, by various interactions, wishful thinking, drinking of one’s own kool-aid, a system is placed on an inexorable path to failure. Without something to divert it in time, failure is the most … Read moreSystems that are designed to fail, often do

With every update, MacOSX becomes harder to build for

2018-12-02 by joe

Way back in the good old 90s, we had very different versions of various unix systems. SunOS/Solaris, Irix, AIX, HP/UX, this upstart Linux, and some BSD things floating about. Of course, windows NT and others were starting to peek out then, and they had a “POSIX subsystem”. Cross platform builds were generally speaking, a nightmare. … Read moreWith every update, MacOSX becomes harder to build for

Opening keynote @Supercomputing #SC18 : #HPC is an enabling technology …

2018-11-13 by joe

… Ok, the speaker said far more than that. But one of his central theses is that in this “second” machine revolution, we are enabling data driven decision making, distributed decision and consensus, as well as expanding beyond the confines of specific expertise in a field. The latter I’ve heard described as cross fertilization … … Read moreOpening keynote @Supercomputing #SC18 : #HPC is an enabling technology …

#HPC in all the things

2018-11-09 by joe

I read this announcement this morning. Our friends at Facebook releasing their reduced precision server side convolution and GEMM operations. Many years ago, I tried to convince people that HPC moves both down market, into lower cost hardware, as well as more widely into more software toolchains. Basically, the decades of experience building very high … Read more#HPC in all the things

Looking forward to #SC18 next week and a discussion of all things #HPC

2018-11-06 by joe

I’m attending SC18 next week. It’s been 3 years since I last attended (2015). Then we (@scalableinfo) had a large booth, lots of traffic, and showed off some of the first commercial NVMe high performance storage systems running BeeGFS over 100GbE. I am looking forward to talking with as many people as I can, to … Read moreLooking forward to #SC18 next week and a discussion of all things #HPC

A bug in s3 buckets with no apparent way to request support to deal with it

2018-09-25 by joe

This is a fun one, I’ve been playing with for the last 5 days or so. I’m helping someone out with backups, and they changed their mind on what they wanted backed up. So I started deleting the backups they didn’t want. One of the machines contained a set of directories for hashdeep which includes … Read moreA bug in s3 buckets with no apparent way to request support to deal with it

Finally posted Tiburon on github

2018-08-21 by joe

Tiburon specifically solves the problem of stateful vs stateless boots, roll forward/backwards in images, consistent booting with immutable images. Coupled with an image generator and a programmatic config environment (as in Nyble and other tools), you have the workings of the non storage/networking parts of a cloud or cluster manager. The philosophy behind this has … Read moreFinally posted Tiburon on github