Category: Technology

Categories
Computing Technology Web

Firefox Slow to Startup, Using Large Amounts of RAM?

Part of my structure and workflow with browsers – Firefox in this case – and one of the innovations I use to structure my browser is Pinned Tabs. Depending on the browser – different machines have different contexts and so different sets of Pinned Tabs in their browsers – I could have between 6 and 12 tabs pinned in the tab bar.

It took quite a while for me to realize it, but slowly my browser startup and performance was becoming very poor. Especially for those occasional links clicked when Firefox is not already open. Today it occurred to me that I’m well aware that Normal Tabs load their content on-demand when first switched to, and not immediately on browser startup. But is this the same for Pinned Tabs?

A quick test showed that Pinned Tabs load all their content immediately when the browser is started. I had my most resource-heavy web apps in those pinned tabs (Webmail, Slack, Trello, Feedly, and more) and they were inflating the startup memory overhead of Firefox by hundreds of megabytes.

Fortunately, as with most things Firefox, in about:config it’s a quick change to browser.sessionstore.restore_pinned_tabs_on_demand to prevent those heavy pages from loading immediately on browser start and rather have them load more comfortably when I actually need them.

Categories
SysAdmin Technology

Subnetting and CIDR, a Pain in the Ass Worth Knowing

When it comes to networking, CIDR and subnetting are not something I’m particularly good or fast at because I haven’t bothered to memorize the most popular subnets – things like /22, 255.255.248.0 and blah. I was taught to work it out in binary, which is a pain in the ass, but correct. So because I tend to not memorize things I can work out, it fell into that category in my head, and has just never stuck. I do absolutely understand the concepts though.

I had a telephone interview with Google years ago where they asked me how many usable IP addresses there were in a certain subnet. I think I looked at the ceiling for a second, gave a hmmm, and just guessed an answer – it felt like the pressure was on providing a fast answer off the top of my head rather than a worked-out one, which was the wrong approach and a mistake. I was ill-prepared for that whole interview anyway and at the very least I should have had a pen and paper with me so I could walk through the process, which I do know. Or perhaps I only know it now because of that experience.

Either way, the point is subnetting is methodical and whether you can spit subnet ranges off the top of your head or do it with a binary calculator it doesn’t matter. Just be right. Or know how to find it on the Internet. And be sure to know how it works so you can prove you’re right when people say you’re wrong – I regularly bump heads with network engineers who’ve never managed to comprehend the underlying composition of subnets, hosts and subnet masks and then I have to try to very diplomatically teach them one of the basics of their profession. The Wikipedia page is most of what you need.

Categories
Technology Web

August Browser Tab Round-Up

Security
http://dev-sec.io/index.html
https://www.inspec.io/
https://kali.training/
https://github.com/laramies/theHarvester
https://modmyi.com/content/22198-myriam-security-challenges-exploit-education-tool-scores-update.html

Linux
https://www.cyberciti.biz/faq/how-to-movemigrate-lxd-vm-to-another-host-on-linux/

Queueing in the Linux Network Stack


https://www.vultr.com/docs/how-to-deploy-google-bbr-on-centos-7
https://serversforhackers.com/s/docker-in-development
https://learn.chef.io/
https://dnsdiag.org

Solaris FMD logs

Oracle Big Data
http://www.oracle.com/technetwork/database/bigdata-appliance/oracle-bigdatalite-2104726.html#movieplex
http://www.oracle.com/partners/en/knowledge-zone/applications/big-data-study-guide-3032976.pdf
https://apexapps.oracle.com/pls/apex/f?p=44785:141:0::NO:141:P141_PAGE_ID,P141_SECTION_ID:27,615

https://pythonhosted.org/python-hpilo/index.html

Exadata
https://karlarao.wordpress.com/2012/05/14/iosaturationtoolkit-v2-with-iorm-and-awesome-text-graph/
http://karlarao.tiddlyspot.com/#%5B%5Bawr_iowlexa.sql%20-%20Hierarchy%20of%20Exadata%20IO%5D%5D
http://www.databasejournal.com/features/oracle/monitoring-smart-flash-cache-activity-on-oracle-exadata.html

Geography

National Park Maps

Coding
https://www.golang-book.com/books/intro

Open Source Projects
https://dapulse.com/
https://www.passbolt.com/

Music
http://www.themetimeradio.com/
http://lifehacker.com/learn-the-basics-of-music-theory-with-this-interactive-1796329461

Weather
https://www.ventusky.com

Windows
http://www.dell.com/support/article/us/en/19/sln208643/how-to-turn-your-windows-laptop-into-a-wifi-hot-spot?lang=en

Categories
Computing Technology

Playing with Bitcoin

Blockchain and Bitcoin are still way too complex for mainstream adoption.
Here are some links I’ve had to use over the past weeks to manage a few simple transactions.
(Don’t trust these links – rather visit the sites directly – there’s a lot of mischief in this space)

https://blockchain.info – Bitcoin wallets, status, API
Note – not easy to get the private keys to one’s wallet, had to go through a BIP39 mnemonic conversion from https://github.com/iancoleman/bip39
More on blockchain.info private key management here: https://bl4nkcode.info/bitcoin/how_to_export_blockchain_wallet_private_key#bip39-standalone.html

Don’t underpay your Bitcoin transfer fees – you’ll get your money stuck for eternity.
https://support.21.co/bitcoin/transactions-and-fees/what-happens-when-a-fee-is-too-low
Check the current fee levels here: https://bitcoinfees.21.co/
If your coin does get stuck, luckily there’s CPP – Child Pays for Parent – perform a child transaction with one of the outputs (hopefully you have leftover coin to work with) and bump up the fee to the total satoshis per byte that it should have been for all your stuck transactions in that chain – Blockchain.info will give you each transaction size in bytes and you’ll need to multiply it out.

https://pool.viabtc.com/tools/txaccelerator/ – Bitcoin transaction accelerator (free), uhm, whatever.

BitAddress has paper wallet options.

https://blockexplorer.com/ Blockexplorer, among other features, will give you details on how fast blocks are completing, which should give a rough idea of the state of mining.

https://coinb.in/ Coinbin is the coolest – a javascript based in-browser wallet and manual transacting system.
If you can use this tool effectively you probably understand blockchain. It’s not for those who are careless with security or those who don’t want to perform very manual bitcoin transactions. They also offer a wallet, but best be careful you don’t make a mistake.

https://coinmarketcap.com/ – What are the total values of each of these currencies? Hint: a lot smaller than the values of the dotcom giants.

Bitcoin Cash
https://bcc-wallet.btc.com A Bitcoin Cash wallet. Very rudimentary, but does the job for this alt currency.

http://blockdozer.com/insight/status Blockdozer for insights into Bitcoin Cash addresses, blocks and transactions.

https://www.bitfinex.com/stats Bitfinex cryptocurrency data and charts

https://www.blocktrail.com/BCC Bitcoin Cash blockchain and block insights, including visibility to the test networks.

http://www.techradar.com/how-to/how-to-claim-bitcoin-cash-bcc-using-the-electron-cash-wallet Get your Bitcoin Cash

Other
https://chain.com/ – Roll your own blockchain…

https://www.rootproject.co/ – An Ethereum based project, let’s see if their noble plan works…

Convert between cryptocurrencies at: https://www.shapeshift.io and https://changelly.com

Categories
Computing SysAdmin Technology Web

April 2017 Browser Tab Round-Up

Development
https://store.digg.com/sales/xamarin-bundle-cross-platform-development?utm_source=digg.com&utm_medium=referral&utm_campaign=xamarin-bundle-cross-platform-development_012117&utm_term=scsf-213321
https://store.digg.com/sales/the-python-power-coder-bonus-bundle?utm_source=digg.com&utm_medium=referral&utm_campaign=the-python-power-coder-bonus-bundle_012117&utm_term=scsf-213318
https://code.visualstudio.com/

Literature
http://lifehacker.com/the-20-best-books-of-2016-according-to-36-best-of-li-1790560969

Infrastructure
https://hyper.is/
https://envoyer.io/
https://serversforhackers.com/
https://forge.laravel.com/features
https://quickadminpanel.com
https://spark.laravel.com/

Reducing latency spikes by tuning the CPU scheduler


https://medium.freecodecamp.com/how-we-fine-tuned-haproxy-to-achieve-2-000-000-concurrent-ssl-connections-d017e61a4d27
https://github.com/fardog/secureoperator
https://developers.google.com/speed/public-dns/docs/dns-over-https
https://dns.google.com/query?name=google.com&type=A&dnssec=true

GoTTY – Share Your Linux Terminal (TTY) as a Web Application


New Draft NIST standards for password management

“Verifiers SHOULD NOT impose other composition rules (e.g., mixtures of different character types) on memorized secrets. Verifiers SHOULD NOT require memorized secrets to be changed arbitrarily (e.g., periodically) and SHOULD only require a change if the subscriber requests a change or there is evidence of compromise of the authenticator.”

https://pages.nist.gov/800-63-3/sp800-63b.html