Very interesting trial of ground-based plates to reduce wingtip vortices near Vienna airport.
If this works, airports can reduce in-trail distance, allowing more landings and takeoffs per hour. The A380 has such a major vortex problem that airport passenger capacity is reduced by the delay time needed after it departs for other aircraft.
Could inspire other real-time control of aerodynamics, somewhat similar to adaptive optics in astronomy.
For example, transsonic shock waves “dance” at approx. 60 Hz across the fuselage and control surfaces of aircraft, and the forward-swept X-29 used a dancing canard to stabilize flight.
This project was sponsored by the German Aerospace Center (DLR), their equivalent of NASA. State organizations play a very important role in fundamental aerospace research, with the X-Planes program influencing the design of every airliner.
Note movable ground-based parallel green plates that dampen vortices. Wingtip vortices are the result of induced drag, and roll off the wingtips – they have upset smaller airliners and businzess jets.
ainonline.com: Wake Vortex Reduction Trials Go Live at Vienna Airport
PSA: It’s possible to move a MacBook Pro notebook SSD drive to another similar model of the same year, with two exceptions:
1) the new computer needs the firmware for that filesystem version. For example, if the SSD used APFS (10.13 and later) and the target computer used only HFS (10.12 and earlier), then it will not boot or even recognize the volume.
The dreaded Mac question-mark folder icon. It indicates no boot device was recognized.
2) The new computer also needs the same level of other firmware (EFI) to boot. Otherwise, you’ll see the “folder with a question mark icon” upon boot, and when using the Disk Utility startup menu, you will not see the SSD drive (just an empty startup options list.)
Also, if your App Store account does not have a linked payment method, the highest version of Mac OS X that can be downloaded is High Sierra, as of July 1, 2019. (No Mojave for you!)
support.apple.com: File system formats available in Disk Utility on Mac
Stoked to hear that Microsoft is working on a release of Flight Simulator 2020, for the Xbox and PC (Windows 10).
Besides being one of the top-selling games of all time, I got my IFR airplane rating in the minimum number of training hours on the first test ride thanks to practising procedures with FS5. That $50 program saved me over $1000 in block time. 🙂
After MS stopped developing it around 2009, they licensed the ESP version to Lockheed Martin as Prepar3d, restricted for non-consumer use for around $200. In other words, it’s military-grade simulator software.
The rumor is that FS was Bill Gates’ “personal hobby project”, and that one year after he stepped down it was killed off.
If you can’t wait for FS2020, the free and Open Source Flightgear is pretty nice too, with photorealistic sky and terrain rendering. Some enterprising folks even box it for sale.
avweb.com: Microsoft Revives Flight Simulator
I had a chance to talk to a Big Data sales manager 5 years ago.
He said, “Hadoop is a tough sale on the East Coast. Hoping Spark will help.”
Now, MapR is facing insolvency and Cloudera/Hortonworks isn’t doing great.
Some of the reasons Hadoop has lost its lustre:
- Commercial Hadoop is licensed per server ($5,000+) times the number of cluster nodes ($millions)
- Hadoop requires rewriting any current reporting jobs using Java/Mapreduce. Large companies tend to not formally budget for maintenance or re-QA of existing applications
- Hadoop jobs tend to be duplicated for different departments and salespersons compared to dedicated internal reporting projects. Yahoo! went from 10 servers to around 1,000 Hadoop nodes for one of their datawarehouses
- Google, the inventor of Mapreduce, used C, which resulted in 3x faster results than Java, and have moved onto other graph systems, like Pregel, a graph database
- vendors declined to monetize their distributed file system as a stand-alone product, resulting in salesmen and technical buyers being at odds.
DBA Pro Tip: Don’t use Hadoop, instead use summary tables and aggressive data retention. AWS has volumes large enough to avoid distributed systems entirely.
Cloudera plummets 40% after CEO abruptly departs and company cuts forecast
An Update from MapR “As a privately held company we are unable to provide forward-looking statements regarding financial performance.” – Really?
theregister.co.uk: MapR misses deadline for sale, biz prospects looking thinner than a Hadoop sales pitch
Luke Demi from Coinbase (YC) gave a talk on “Observability for Startups” tonite at the AWS Loft at 525 Market Street. Video
He talked about their odyssey through the years to monitor their infrastructure, now over 5,000 AWS servers (originally Ruby on Rails and Mongo) and serverless (AWS Lambda.)
Like most startups, they don’t have a DBA team because features. So they rely on monitoring during outages to tell them when to run EXPLAIN. 🙂
EXPLAIN is your friend!
They have used or evaluated several products over the years:
New Relic – likely too expensive
- Kibana – based on logs, so detailed, but poor aggregation and alerting. Only can afford to store 7 days. Dashboard with 100 ms/200 ms and 500s graphs. They use AWS-managed services as much as possible to reduce workload.
Grafana/Prometheus – too DIY, poor alerting UI
- Datadog – good aggregation and alerting, easiest for new engineers, long retention, poor details and granularity. Special VPC routing for eng. security.
Kibana vs. Datadog – Complementary Features
Now using Kibana and Datadog, which are literally complementary (see slides
) but would like to combine the best of both into one tool. Maybe someday! 🙂
For serverless (AWS lambda), either AWS X-ray with Datadog, or Cloudwatch.
As a finance company, Coinbase does spend effort on compliance, though it’s a Cloud world now.
Coming soon: AWS Database Week in SF from June 4-6.
AWS: Patching Python Libraries to Instrument Downstream Calls
bloomberg.com: Coinbase Says Chief Operating Officer Has Left Crypto Exchange
Firefox zero-day was used in attack against Coinbase employees, not its users