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Showing posts from May, 2017

[HDGEM] Google Compute Engine users will now be able to attach up to 455 GB of memory per VM instance

Google Compute Engine users will now be able to attach up to 455 GB of memory per VM instance when they opt for building their own custom machine type and choose the new extended memory option. Previously, you had to adhere to a certain ratio between memory and the number of virtual CPUs that topped out at 6.5 GB.

Posted By Blogger to HDGEM at 5/31/2017 08:01:00 PM

[HDGEM] Typing `npm install [email protected] -g` will update you to npm version 5.0.1.

[email protected] is all new and packed with performance, reliability, and usability improvements.

These include a new approach to lockfiles, more robust caching, and incredible speed — for many common tasks, [email protected] is up to 5x faster than previous versions.

Posted By Blogger to HDGEM at 5/31/2017 05:35:00 PM

[HDGEM] Percona XtraDB Cluster provides a cost-effective, robust solution for businesses.

Percona XtraDB Cluster enables applications requiring synchronous replication of data to have fault tolerant failover and quick, easy scalability across commodity and off-the-shelf hardware. Organizations use Percona XtraDB Cluster to power highly available applications in the most demanding public, private and hybrid cloud environments.

Posted By Blogger to HDGEM at 5/31/2017 08:18:00 AM

[HDGEM] MySQL Router is part of InnoDB cluster, and is lightweight middleware that provides transparent routing between your application and back-end MySQL Servers.

MySQL Router can be used for a wide variety of use cases, such as providing high availability and scalability by effectively routing database traffic to appropriate back-end MySQL Servers. The pluggable architecture also enables developers to extend MySQL Router for custom use cases.

Posted By Blogger to HDGEM at 5/31/2017 07:37:00 AM

[HDGEM] How to copy files to remote server with sudo

With SCP, you have to do in two steps, however, you can do it in one with rsync as follows: rsync --rsync-path="sudo rsync" <LOCALFILE> [email protected]:/root Note: This does require NOPASSWD sudo. use --rsync-path option to make rsync run with sudo. The following command correctly creates all the directories and syncs the files as expected. rsync -rvR --rsync-path="mkdir -p /srv/backupdir/Linux/sync/ && rsync" <LOCALFILE> [email protected]:/root

Posted By Blogger to HDGEM at 5/31/2017 06:54:00 AM

[HDGEM] rsync vs scp

scp basically reads the source file and writes it to the destination. It performs a plain linear copy, locally, or over a network. rsync also copies files locally or over a network. But it employs a special delta transfer algorithm and a few optimizations to make the operation a lot faster.

Posted By Blogger to HDGEM at 5/31/2017 06:28:00 AM

[HDGEM] rsync Encryption

rsync performs no encryption on its own. If you don't use ssh, nor do you tunnel the rsync traffic through stunnel or some kind of VPN, then no encryption is performed. 
If you use the rsync:// protocol scheme (i.e. when you connect to a rsyncd daemon) then no encryption will be used (although password authentication is done using a MD4-based challenge-response system and is probably still reasonably secure).
If you use the hostname:/some/path scheme then rsync transparently calls SSH, which encrypts everything, and uses SSH's native authentication mechanisms. 

Posted By Blogger to HDGEM at 5/31/2017 06:27:00 AM

[HDGEM] How cloud services typically ensure data consistency

Most distributed cloud services take one of two approaches to ensuring data consistency:

One approach, strong consistency, doesn't allow reads until all associated writes are complete. Any read always returns the latest version of an item. If you use strong consistency for your data, your application is only as fast as the latency among all the regions where you store data.

The other approach, eventual consistency, is a lazier approach to working with data. It's more focused on applications that need to read data as soon as it's written. Data is read at any time, but there's a risk that it could be changed by another write. That leaves you with a level of indeterminacy in your data: You know at some point it's going to be accurate, just not when that will be. Data may arrive in any order, so don't use eventual consistency for series data. There's even the chance that if you read the same item twice, the second time could return older data than the first.…

[HDGEM] the dead letter queue in message queueing

In message queueing the dead letter queue is a service implementation to store messages that meet one or more of the following criteria : Message that is sent to a queue that does not exist. Queue length limit exceeded. Message length limit exceeded. Message is rejected by another queue exchange.

Posted By Blogger to HDGEM at 5/30/2017 12:42:00 PM

[HDGEM] High performance of ProxySQL

ProxySQL has an advanced multi-core architecture. It's built from the ground up to support hundreds of thousands of concurrent connections, multiplexed to potentially hundreds of backend servers. The largest ProxySQL deployment spans several hundred proxies.

Posted By Blogger to HDGEM at 5/30/2017 12:27:00 PM

[HDGEM] The MySQL query cache is a query results cache.

The MySQL query cache compares incoming queries that start with SEL to a hash table, and if there is a match returns the results from the previous execution of the query. There are some restrictions:

The query must match byte-for-byte (the query cache avoids parsing)
Use of non-deterministic features will result in the query not being cached (including temporary tables, user variables, RAND(), NOW() and UDFs.)
The query cache was designed to not serve stale results.  Any modification to the underlying table(s) results in all cache being invalidated for those tables.
There are some restrictions on if the cache can be used for InnoDB (to respect MVCC; as you have a transaction open, the 'cache' might not represent the data in your expected view.)

Posted By Blogger to HDGEM at 5/30/2017 12:21:00 PM

[HDGEM] Main advantage of Google Cloud

Google says the main advantage it holds over other major tech companies that offer cloud services like Microsoft and Amazon, is that along with traditional storage, the tech giant also provides algorithms to help make more sense of massive amounts of data. 

Posted By Blogger to HDGEM at 5/30/2017 09:25:00 AM

[HDGEM] Decoupling the components of an application by message service

You have a queue of work items and want to track the successful completion of each item independently. Message service tracks the ACK/FAIL results, so the application does not have to maintain a persistent checkpoint or cursor. After a configured visibility timeout, Message service deletes acknowledged messages and redelivers failed messages.

Posted By Blogger to HDGEM at 5/30/2017 09:10:00 AM

[HDGEM] Notification Settings of Google Forms

You can get real-time notifications when people fill out your form.  It's incredibly easy to set up. All you have to do is go to Tools and Notification Rules, and choose what type of notifications you would like to get such as, in a batch or individual.

Posted By Blogger to HDGEM at 5/30/2017 07:46:00 AM

[HDGEM] Intel Core X models will improve multitasking performance

<span style="color: rgb(66, 66, 66); font-family: Helvetica,
sans-serif; font-size: 18px; -webkit-tap-highlight-color: rgba(26, 26,
26, 0.301961); -webkit-text-size-adjust: 100%; background-color:
rgb(255, 255, 255);">Intel claims that the Core X series reaches 10
percent faster multithread performance over the previous generation,
and 15 percent faster single thread.</span>

Posted By Blogger to HDGEM at 5/30/2017 01:40:00 AM

[HDGEM] How to connect Spring Boot Application to database

Spring Boot gives you defaults on all things, the default in database is H2, so when you want to change this and use any other database you must define the connection attributes in the file. Example: In the sources folder, you create a resource file src/main/resources/ spring.jpa.hibernate.ddl-auto=create spring.datasource.url=jdbc:mysql://localhost:3306/db_example spring.datasource.username=springuser spring.datasource.password=ThePassword

Posted By Blogger to HDGEM at 5/29/2017 01:41:00 PM

[HDGEM] How to show maven dependency tree from command line

$ mvn dependency:tree
[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] Building demo 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] --- maven-dependency-plugin:2.10:tree (default-cli) @ demo ---
[INFO] com.example:demo:jar:0.0.1-SNAPSHOT
[INFO] +- org.springframework.boot:spring-boot-starter:jar:1.5.3.RELEASE:compile
[INFO] |  +- org.springframework.boot:spring-boot:jar:1.5.3.RELEASE:compile
[INFO] |  |  \- org.springframework:spring-context:jar:4.3.8.RELEASE:compile
[INFO] |  |     +- org.springframework:spring-aop:jar:4.3.8.RELEASE:compile
[INFO] |  |     +- org.springframework:spring-beans:jar:4.3.8.RELEASE:compile
[INFO] |  |     \- org.springframework:spring-expression:jar:4.3.8.RELEASE:compile
[INFO] |  +- org.springframework.boot:spring-boot-autoconfigur…

[HDGEM] The Software Development Kit Manager

SDKMAN! is a tool for managing parallel versions of multiple Software Development Kits on most Unix based systems. It provides a convenient Command Line Interface (CLI) and API for installing, switching, removing and listing Candidates.

Get started now! Go on, paste and run the following in a terminal: 
$ curl -s "" | bash

Posted By Blogger to HDGEM at 5/29/2017 12:39:00 PM

[HDGEM] The Spring Boot CLI is a command line tool that can be used if you want to quickly prototype with Spring.

The Spring Boot CLI allows you to run Groovy scripts, which means that you have a familiar Java-like syntax, without so much boilerplate code.

You don't need to use the CLI to work with Spring Boot but it's definitely the quickest way to get a Spring application off the ground.

Posted By Blogger to HDGEM at 5/29/2017 12:35:00 PM

[HDGEM] The spring-boot-starter-data-jpa POM provides a quick way to get start of the Java Persistence API

The Java Persistence API is a standard technology that allows you to 'map' objects to relational databases.  The spring-boot-starter-data-jpa POM provides the following key dependencies: Hibernate — One of the most popular JPA implementations.Spring Data JPA — Makes it easy to implement JPA-based repositories.Spring ORMs — Core ORM support from the Spring Framework.

Posted By Blogger to HDGEM at 5/29/2017 11:34:00 AM

[HDGEM] Spring DataSource configuration is controlled by external configuration properties in spring.datasource.*.

For example, you might declare the following section spring.datasource.url=jdbc:mysql://localhost/test spring.datasource.username=dbuser spring.datasource.password=dbpass spring.datasource.driver-class-name=com.mysql.jdbc.Driver

Posted By Blogger to HDGEM at 5/29/2017 11:31:00 AM

[HDGEM] Spring hibernate property


You can set this property to the following values:

none, validate, update, create-drop. 

For a production database, you probably would want to use validate.
For a development database, you probably would want to use create-drop.

Posted By Blogger to HDGEM at 5/29/2017 11:27:00 AM

[HDGEM] MySQL Maven Dependencies

First we need to add the MySQL database drivers to our project. You will need to add the following dependency to your Maven POM file. POM.xml <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency>

Posted By Blogger to HDGEM at 5/29/2017 11:21:00 AM

[HDGEM] How to output file name from grep

-L, --files-without-match Suppress normal output; instead print the name of each input file from which no output would normally have been printed. The scanning will stop on the first match. -l, --files-with-matches Suppress normal output; instead print the name of each input file from which output would normally have been printed. The scanning will stop on the first match.

Posted By Blogger to HDGEM at 5/29/2017 10:55:00 AM

[HDGEM] iPhone 7 dramatically improves the most important aspects of the iPhone experience.

iPhone 7 introduces advanced new camera systems. The best performance and battery life ever in an iPhone. Immersive stereo speakers. The brightest, most colorful iPhone display. Splash and water resistance.1 And it looks every bit as powerful as it is. This is iPhone 7.

Posted By Blogger to HDGEM at 5/29/2017 06:40:00 AM

[HDGEM] Siri Eyes Free is an extension of Apple's Siri functionality for enabling voice control of an iOS mobile device that is linked with a car's in-dash audio system.

With Siri Eyes Free, drivers can speak natural language voice commands in order to operate the mobile device as well as the car's sound or in-vehicle infotainment system.
Siri Eyes Free operates via a voice command button on the car's steering wheel, enabling the driver to make and receive calls, select and play music, audibly send and receive text messages, access Maps and get directions, audibly receive notifications, set reminders and more.

Posted By Blogger to HDGEM at 5/28/2017 09:18:00 AM

[HDGEM] CarPlay is an iOS feature that makes using your iPhone simpler and easier while in the car.

How Apple describes CarPlay:

Available on select cars, CarPlay is a smarter, safer way to use your iPhone in the car. CarPlay takes the things you want to do with your iPhone while driving and puts them right on your car's built-in display. You can get directions, make calls, send and receive messages, and listen to music, all in a way that allows you to stay focused on the road. Just connect your iPhone and go.

Posted By Blogger to HDGEM at 5/28/2017 09:15:00 AM

[HDGEM] Siri Eyes Free allows drivers to use a button on the steering wheel to activate Siri

Siri Eyes Free allows drivers to use a button on the steering wheel to activate Siri and carry out a limited number of functions, while the iPhone screen remains off to avoid the temptation to look at it whilst driving.

Siri Eyes Free allows drivers to call people in their Contacts, dictate and listen to text messages, check & add calendar appointments, check the weather, set reminders and of course play music, all via voice.

Posted By Blogger to HDGEM at 5/28/2017 09:13:00 AM

[HDGEM] What Google Lens can do for you

Tell you what species a flower is just by viewing the flower through your phone's camera;
Read a complicated Wi-Fi password through your phone's camera and automatically log you into the network;
Offer you reviews and other information about the restaurant or retail store across the street, by you just flashing your camera over the physical place.

Posted By Blogger to HDGEM at 5/28/2017 09:03:00 AM

[HDGEM] The opportunity to work from anywhere.

Entrepreneurship in a digital era presents a unique lifestyle choice for today's business owners: the opportunity to work from anywhere. All you need is a laptop and an internet connection to run your online business on the go.

Posted By Blogger to HDGEM at 5/28/2017 08:25:00 AM

[HDGEM] Docker multi-stage builds

The docker multi-stage build feature helps you create thin Docker images by making it possible to divide the image building process into multiple stages.
Artifacts produced in one stage can be reused by another stage.

Posted By Blogger to HDGEM at 5/28/2017 05:57:00 AM

[HDGEM] Function-as-a-Service (FaaS)

FaaS features

Complete abstraction of servers away from the developer
Billing based on consumption and executions, not server instance sizes
Services that are event-driven and instantaneously scalable

Posted By Blogger to HDGEM at 5/28/2017 05:27:00 AM

[HDGEM] Personal is a new option of Google Search that is not integrated directly in the algorithm that determines which search results are returned to users when they run searches on Google.

It is a new option under the more link instead which you can load. Please note that personal is only an option there if you are signed in to a Google account, and that the new feature won't work yet for Google Apps customers.

Posted By Blogger to HDGEM at 5/28/2017 05:19:00 AM

[HDGEM] How do you change the voice on Google Maps on iPhone?

Launch Google Maps and tap the three bars to open the menu, then Settings, then Voice Search. This is where you can change the voice setting. If the default is not what you'd like it to be open your iPhone settings, tap General, then Language & Region and adjust accordingly.

Posted By Blogger to HDGEM at 5/27/2017 07:15:00 PM

[HDGEM] Google Photo is smart and free.

You can upload unlimited photos to Google Photos (although compressed), without paying a dime. Also, once your photos are in there, you can do a lot of interesting things.

Posted By Blogger to HDGEM at 5/27/2017 05:22:00 PM

[HDGEM] Night Mode on Chrome OS

Like on many Android smartphones today, including the Pixel, Night Mode on Chrome OS removes as much blue light as possible from the display by adding a yellow-ish hue. This new slider simply enables users to tweak the intensity of that setting.

Posted By Blogger to HDGEM at 5/27/2017 05:17:00 PM

[HDGEM] Microsoft is working on channelling Windows 10 Pro for ARM devices

Microsoft earlier revealed plans for yet another low-end optimised, sleek version of Windows 10 in order to take on ChromeOS. This isn't the first version of Windows to take on Chromebooks, and it probably won't be the last. Microsoft is also working on channelling Windows 10 Pro for ARM devices, so hardware manufacturers can make use of cheaper Qualcomm SOCs for their devices.

Posted By Blogger to HDGEM at 5/27/2017 08:28:00 AM

[HDGEM] Matebook E specs

2,160x1,440-pixel resolution touchscreen
Intel M3 or i5 CPU
4GB/8GB RAM (8GB only in US)
128GB/256GB/512GB internal storage
USB-C port
Estimated 9-hour battery life

Posted By Blogger to HDGEM at 5/27/2017 08:25:00 AM

[HDGEM] The Huawei Matebook E tablet

The Huawei Matebook E is an updated version of last year's model. The Windows 10 tablet was notable for its iPad Pro-like chassis, but didn't include the keyboard case in its base price.

The new 12-inch tablet corrects that mistake by throwing in the luxe leather keyboard accessory, as well as packing a higher 2K-resolution screen and offering an optional upgrade to an Intel i5 processor.

Posted By Blogger to HDGEM at 5/27/2017 08:24:00 AM

[HDGEM] Huawei Matebook X specs

2,160x1,440-pixel resolution screen (non-touch)
Intel Core i5 or i7 CPU
256GB/512GB SSD
Full-size Chiclet backlit keyboard
Two USB-C ports
Includes multiport adapter
Estimated 10-hour battery life

Posted By Blogger to HDGEM at 5/27/2017 08:22:00 AM

[HDGEM] Photos for iOS. Bringing all your memories into focus.

You've never experienced your photos quite like this. With the new Memories feature, Photos helps you rediscover favorite and forgotten moments. And advanced search technology and editing tools let you find, share, and remaster your photos in entirely new ways.

Posted By Blogger to HDGEM at 5/27/2017 07:32:00 AM

[HDGEM] Google cloud Committed Use Discounts

Google cloud Committed Use Discounts are similar to AWS's Reserved Instances but without the upfront fees or lock-in to a particular instance type, netting up to a 57 percent discount.

Posted By Blogger to HDGEM at 5/27/2017 01:22:00 AM

[HDGEM] How do I open directory inside Vim?

Try :Ex[plore]. From :help Ex: :Explore will open the local-directory browser on the current file's directory (or on directory [dir] if specified). The window will be split only if the file has been modified, otherwise the browsing window will take over that window. Normally the splitting is taken horizontally.

:Sex command. It does the split window for you, and drops you into the current directory. :Sex path/to/dir

Posted By Blogger to HDGEM at 5/26/2017 07:02:00 AM

[HDGEM] DoubleClick for Publishers is a single platform that allows you to manage and deliver all of your web, mobile, and video advertising across all your sales channels.

DoubleClick for Publishers doesn't come with it's own ads, but rather helps you scale your ads business by managing your ad sales across a variety of ad networks such as AdSense, ad exchanges like DoubleClick and direct advertising partners.

Posted By Blogger to HDGEM at 5/26/2017 01:06:00 AM

[HDGEM] The main difference between DoubleClick Ad Exchange and AdSense

DoubleClick Ad Exchange gives you real-time access to the largest pool of advertisers.The main difference between DoubleClick Ad Exchange and AdSense is that AdSense does a lot of the technical settings and optimization work for you, such as automating the sale of all your ad space to the highest bidder. With DoubleClick Ad Exchange you manage these adjustments yourself, controlling exactly how your inventory is sold.

Posted By Blogger to HDGEM at 5/26/2017 12:53:00 AM

[HDGEM] How to set up canned responses in Google inbox

There are answers to common questions that you're asked via email.

Go to settings then labs. Search canned responses, click enable, and then save. When you compose an email, there's an arrow in the bottom right corner. Just hover over canned responses and save the canned response.

Posted By Blogger to HDGEM at 5/25/2017 07:26:00 PM

[HDGEM] How to increase GlassFish server asadmin deployment timeout

If your app is big, you might encounter the following when deploying it:

No response from Domain Admin Server after 600 seconds. The command is either taking too long to complete or the server has failed. Please see the server log files for command status. Command deploy failed.

One way to fix it is to increase GlassFish server asadmin deployment timeout. The default deployment timeout value of asadmin is 600 seconds. You can set the environment variable AS_ADMIN_READTIMEOUT to increase the asadmin deployment timeout from 600 seconds to 3600 seconds.
export AS_ADMIN_READTIMEOUT="3600000"or put it to glassfish/conf/asenv.conf.

Posted By Blogger to HDGEM at 5/25/2017 04:27:00 PM

How to backup and restore domain in Glassfish / Payara Java EE application Server

1.  Execute asadmin utility of your Glassfish distribution. 2.  Stop your domain if it’s running by issuing stop-domain <YOUR DOMAIN NAME> command. 3.  Run backup-domain <YOUR DOMAIN NAME>. 4.  After executing the backup domain command, your backed up domain is located under glassfish_ home/domains/<YOUR DOMAIN NAME>/backups  directory a .zip file. 5.  Copy the generated .zip backup file to other location. 6.  Now delete your existing domain by issuing delete-domain <YOUR DOMAIN NAME> command. (optional, since we are going to restore it by force later) 7.  Open your backup file, normally packaged as a zip file. Open the file and change property to your desired name. 8.  Save the file and make sure that the modification is applied to your zip file too. 9.  Bring up asadmin utility up and issue the following command restore-domain --filename <PATH TO BACKUP ZIP FILE> --force 10.  Execute list-domains command to see your doma…