投稿時間:2022-08-18 19:43:44 RSSフィード2022-08-18 19:00 分まとめ(54件)

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IT	InfoQ	Dealing with Cognitive Load Using Observability	https://www.infoq.com/news/2022/08/cognitive-load-observability/?utm_campaign=infoq_content&utm_source=infoq&utm_medium=feed&utm_term=global	Dealing with Cognitive Load Using ObservabilityWe can make good decisions with speed when we limit the cognitive load on any one person or team Observability can help to increase delivery speed by providing information to developers that helps them to make decisions quickly By Ben Linders	2022-08-18 09:03:00
IT	ITmedia 総合記事一覧	[ITmedia Mobile] Xperia PRO／PRO-Iがアップデート　一眼レフカメラで撮った映像をスマホ経由で配信可能に	https://www.itmedia.co.jp/mobile/articles/2208/18/news174.html	ITmediaMobileXperiaPROPROIがアップデート一眼レフカメラで撮った映像をスマホ経由で配信可能にソニーは月日から、プロ用途向けGスマートフォン「XperiaPRO」「XperiaPROI」にソフトウェアアップデートを順次提供している。	2022-08-18 18:30:00
IT	ITmedia 総合記事一覧	[ITmedia ビジネスオンライン] ファミマのフラッペ、2500万杯突破　全品100円引きセールを実施へ	https://www.itmedia.co.jp/business/articles/2208/18/news168.html	famimacafe	2022-08-18 18:09:00
IT	ITmedia 総合記事一覧	[ITmedia Mobile] PayPay、登録ユーザーが5000万人を突破　記念キャンペーンも後日実施	https://www.itmedia.co.jp/mobile/articles/2208/18/news170.html	itmediamobilepaypay	2022-08-18 18:04:00
TECH	Techable（テッカブル）	b8taが3都市でポップアップストア開催。軽のEV「日産サクラ」など19の展示品発表	https://techable.jp/archives/184390	btapopupstore	2022-08-18 09:00:55
AWS	AWS Japan Blog	Synadia が AWS IoT と ML を使用して次世代の錠剤検証システムを構築	https://aws.amazon.com/jp/blogs/news/synadia-builds-next-generation-pill-verification-systems-with-aws-iot-and-ml/	sebastiaanwijn	2022-08-18 09:11:16
AWS	lambdaタグが付けられた新着投稿 - Qiita	Lambda - RDS Proxy(TLSあり) - Auroraの構成でRDS（Aurora）に接続する	https://qiita.com/yuta-katayama-23/items/c543d957694ea37988ab	aurora	2022-08-18 18:32:02
AWS	AWSタグが付けられた新着投稿 - Qiita	Amazon EC2のストレージボリューム（EBS）	https://qiita.com/jaken1207/items/a1f8093758f9ecf31378	amazon	2022-08-18 18:11:22
Azure	Azureタグが付けられた新着投稿 - Qiita	【AutoML】チュートリアルを使って分類モデルを作ってみる【Azure】	https://qiita.com/K-Nomu3/items/7951d53f6aa4e58f236f	automl	2022-08-18 18:25:54
海外TECH	DEV Community	How would you refactor this code? (tennis-3-modern)	https://dev.to/lgrammel/how-would-you-refactor-this-code-tennis-3-modern-40h7	How would you refactor this code tennis modern export class TennisGame constructor pN pN this p this p this pN pN this pN pN getScore let s if this p lt amp amp this p lt amp amp this p this p lt const p Love Fifteen Thirty Forty s p this p return this p this p s All s p this p else if this p this p return Deuce s this p gt this p this pN this pN return this p this p this p this p Advantage s Win for s wonPoint playerName if playerName player this p else this p I ve created a modern version of the Tennis refactoring kata The class calculates the tennis score for a game You can find the full code including a test suite on GitHub How would you refactor it	2022-08-18 09:13:54
海外TECH	DEV Community	9 No-Code Tools You should definitely try in 2022 🔥💯	https://dev.to/aviyel/9-no-code-tools-you-should-definitely-try-in-2022-33ol	No Code Tools You should definitely try in IntroductionThe world around us is changing and the way we do things has to change with it In this case writing codeーand doing so more efficiently than ever beforeーhas become much simpler thanks to the plethora of no code and low code tools available on the market No code development platforms and low code development platforms are similar in that they both drastically reduce the amount of time it takes to create an application Unlike low code no code development platforms don t require any codingーthey offer predesigned templates from which businesses can build apps As companies deal with the parallel trends of an increasingly mobile workforce and a limited supply of competent software developers these platforms have both increased in popularity Popularity and the rise of no code toolsNo code tools have become increasingly popular and thanks to this there are many options for you to choose from No code tools are easy to use affordable and user friendly They also provide the opportunity for developers who are new to coding or those who have limited experience in building websites or apps on their own No code doesn t mean that you won t need any knowledge of coding as some might think It simply means that you don t have to learn how everything works behind the scenes before being able to build something yourself with no prior experience required whatsoever Google AppSheetGoogle AppSheet is a web app that allows you to build a spreadsheet based app without writing any single line of code It s an easy to use tool that allows you to create and customize templates for different types of applications including business apps websites and email marketing campaigns AppSheet also has built in drag amp drop editor so users can quickly add content from the web into their spreadsheets without having to learn how to use coding languages like HTML or JavaScript This makes it a good choice for small businesses and startups who want something simple but powerful at their disposal when they need it most If you re looking for a way to make an app without code check out AppSheet It s absolutely free limited up to users ZapierZapier is a workflow automation tool that connects the apps you use It allows you to automate repetitive tasks and it s free for up to zaps Zapier provides some of the easiest ways to automate your business You can use Zapier s simple and user friendly interface by building automated workflows between apps like Gmail or Slack that allow you to perform complex actions across multiple platforms without writing any code by yourself For example with one click of a button on our website you can automatically send an email reminder when someone signs up for our newsletter using Mailchimp as well as create custom emails with the customer s name in them Zapier is great because it s easy to use and has a lot of integrations with other apps so if you re looking for something that can do more than just one thing at once Zapier might be the right choice for you You can connect hundreds of different apps such as Google Sheets or Asana project management software etc with Zapier And because they offer both free and paid plans starting at just per month there s no risk involved in trying WebflowWebflow is a website builder that lets you create your own website without writing any code Using drag and drop tools it s easy to build a beautiful site in just minutes It also has a powerful suite of marketing tools that will make it easy for you to get the word out about your business online With Webflow you can create a website in just a matter of minutes that looks professional and is mobile friendly It s built for small businesses or individuals who want to build their own websites but don t have the skills to do so This platform has an easy to use interface that allows users of all skill levels to design websites without having any coding experience Webflow is a really awesome tool that enables anyone to design and host their own website without writing any code It s a really very easy to use interface that makes it simple for newbies beginners to easily get started with it The best part about this tool is the fact that you don t need any coding experience but it can be used by professionals as well You can create your own website with Webflow in just minutes and get started right away absolutely free of charge ThunkableThunkable makes it easy for you to build your application in no time whether you re looking for a hands on experience with no code creation or are launching your very own business Its simple drag and drop design canvas and powerful logic blocks allow you to unlock all the benefits of a native mobile and tablet device and also you can add third party power to your app with their open integrationsーconnecting your own database is as easy as it gets Thunkable makes the process of creating apps simple and straightforward With design components including animations logic blocks and open integrationsーthousands of users rely on Thunkable to build custom applications It makes it easy to turn your idea into an app without writing any code so you can try it outーand even customize it ーwithout having to pay a single dime because the personal plan is free Bravo StudioBravo Studio is an app builder for designers and developers It makes it possible to turn Figma prototypes into native iOS and Android applications instantly without writing any codeーand allows users to test their designs on real devices with no hassle Bravo Studio makes use of native components and mobile actions to make your application look like it was developed specifically for that mobile platform With Bravo Studio your prototype can be connected to real time data You can pull and display information from any APIs or third party services The changes to your data will automatically be synchronized and the new information should appear in your app within seconds Bravo Studio offers users a free version of the app as well as a paid subscription to unlock additional features ToolJetToolJet is a no code platform that allows you to create custom apps without coding skills This tool is suitable for any business from start ups to enterprises It has been designed to help you build launch and manage your internal tools quickly and easily This way there are no longer any restrictions when it comes to using our products because they are completely customizable by the user himself or herself ToolJet is a fully open source no code framework for quickly building and deploying internal tools without having to put in a lot of effort Users can connect to databases such as PostgreSQL and MongoDB API endpoints like Stripe s and external servicesーlike Google Sheets In addition to these data sources Tooljet provides UI widget templates that let you build internal tools without writing code KnackKnack is a no code platform that allows you to build apps without writing any code Knack is a really awesome tool for non technical users It makes it easy for non technical users to create apps and publish them on various platforms The best part of this tool however is its ability to customize your app according to your needs and preferences You can choose from multiple templates based on different categories which will help you save time when creating an app because all you have to do is select one or two options Getting started with Knack is easy and you can even try it free for daysーno credit card required After that though a subscription will cost at least month BubbleBubble is a simple and easy to use drag and drop website builder It s great for beginners small businesses and non techies who want an alternative to coding their own web pages With Bubble you can create a website that looks and feels professional without doing any coding This is especially helpful for those who are looking to start their own business or make some extra money online It s also great for non techy people who have no idea how coding works but want their own website anyway Bubble allows you to create beautiful websites in a few minutes by dragging elements from the library onto your page think of it as an easy way to build your first website You can also choose from hundreds of prebuilt templates or start from scratch with custom HTML CSS code if necessary Bubble is free to use but you ll need a subscription plan if you want more advanced features A starter plan costs month while an enterprise one goes for per month MiroMiro is a no code platform for creating and visualizing data that can be stored in a database spreadsheet or third party tool With Miro you can create sprint epics from clusters of sticky notes then export your sketches to preferred design tools for high fidelity prototyping In addition with Miro you can plan across teams and integrate context from all of your other tools into a visual way to see projects or sprints and roadmaps Finally bring together data from multiple sources throughout your business so that the whole story is on one screen ーmaking better decisions for smarter growth In brief Miro is a collaborative platform that enables distributed teams to collaborate effectivelyーfrom brainstorming with digital sticky notes to planning and managing multiple workflows The product comes with a user friendly drag and drop interface that allows beginners to get started without any hassle All of these no code tools will help you build or optimize a business or website quickly and easily without the need to code The era of no code tools is here and it s going to be a big deal for anyone who wants to build or optimize a business or website quickly and easily There are many options for you to choose from so whether you re looking for a tool that will help you build an online store from scratch or one that can help with some of the technical aspects of running your own blog website like hosting there s something out there for everyone This is a growing trend in technology as more people realize how easy it is to create websites without having any programming knowledge at allーand this trend isn t going away anytime soon either because as long as humans use computers we ll always need them even if they don t know how they work No matter what kind of business or website you re looking to build there s a no code tool for it Whether you want something powerful like ToolJet or simpler but still effective options like Bravo Studio you ll find that there are plenty of ways to get started without coding ConclusionThe world is changing and your business needs to change with it If you want to stay competitive in the years ahead you need to be ready for a marathon of development that s never ending The good news is that there are plenty of tools out there designed specifically for this purpose The above mentioned compiled list of nine no code and low code tools is intended to help you get started on your journey to becoming an expert in building and crafting applications without writing a single line of code	2022-08-18 09:13:00
海外TECH	DEV Community	Database Caching Strategies	https://dev.to/kalkwst/database-caching-strategies-16in	Database Caching StrategiesOriginally posted hereMost if not all developers are at least somewhat familiar with the concept of caching After all this technology is so ubiquitous nowadays from CPU to browser caching that all software relies on caching techniques to a certain extent to provide rapid responses A latency of just a few milliseconds can cause millions of loss in revenue so a sub millisecond response is becoming the norm There is a vast number of caching solutions available in the market thus making the process of choosing the right one an adventure on its own In this post we will discuss what a cache is and the benefits of caching Next we will discuss different caching strategies and cache eviction policies Finally we are going to review some existing caching solutions available Caching Fundamentals What is a cache In software development a cache is a component that stores portions of a dataset that would either take too long to calculate or originates from another underlying system By reducing unnecessary calculations and preventing additional request roundtrips for frequently used data can increase the application performance or decrease response latencies Caches are designed to respond to cache requests in near real time and therefore are implemented as simple key value stores The inner workings however can still be very different and depend on backend storage Typical use cases are in memory caches for databases or slowly retrievable disk based data data stored remotely behind slow network connections or results of previous calculations What are a cache hit and a cache miss A cache hit happens when the data requested is already available in the cache and can be returned without any other operation or processing A cache miss happens when the data requested is not already available and the data must be either retrieved from an underlying system or calculated before it can be returned Application Challenges and Caching BenefitsModern systems have to accommodate large volumes of traffic and need to respond blazingly fast Also as the volume of traffic and data increases the applications need to be able to grow to be successful On the other hand most infrastructure relies on disk based databases either directly or indirectly Disk based databases can pose a lot of challenges for distributed applications that require low latency and scalability A few of the most common challenges include Slow processing queries The data retrieval speed from a disk plus the added query processing times generally keeps response times relatively high There are a lot of optimization techniques and designs that can boost query performance However there is a limit to the performance that we can achieve before reaching the physical limitations of the medium A large part of the latency of the database query is dictated by the physics of retrieving data from disk after all Cost of Scalability Databases can be scaled either horizontally or vertically Both of these scaling techniques do have their disadvantages Vertical scaling is both expensive and you can reach the physical limit of components that can be added to a machine Horizontal scaling allows sharding of the database to achieve higher throughput Nonetheless scaling for higher reads can be costly and may require a lot of replicas to achieve Moreover we must be very careful not to become imbalanced while trying to achieve higher response times Availability Sometimes the connection to the database server or a database shard can be interrupted Without a cache the system will become unresponsive until the connection is restored The overall benefit of caching is to aid both the content consumer and content providers A good caching strategy can offer several advantages Improved responsiveness Caches can provide faster retrieval of content and prevent additional network roundtrips Caches maintained close to the user like the browser cache can make this retrieval nearly instantaneous Increased performance on the same hardware For the server where the content originated aggressive caching can be squeezed from the same hardware The content owner can leverage more powerful servers along the delivery path to take the brunt of content loading Decreased network costs Depending on the caching strategy content can be available in multiple regions in the network path That way content can move closer to the user and network activity beyond the cache is reduced Robustness of content delivery With certain policies caching can be used to serve content to end users even when it may be unavailable due to network shortages or server failures Elimination of database hotspots In many applications a small subset of data will likely be accessed more frequently than the rest This can result in hotspots in the database The hotspots may require overprovisioning of database resources based on the throughput requirements for the most frequently used data Storing common keys in an in memory cache mitigates the need for overprovisioning while providing fast and predictable performance What to CacheA good indicator of what to cache is to find any element where multiple executions of some request will result in the same outcome This includes database queries HTML fragments or the output of heavy computations In general only one rule applies Data should not change too often but should be read very frequently What not to CacheA common misconception especially among tech adjacent roles is that if you cache everything you ll automatically benefit from it What often looks like a good idea in the first place causes another problem during high data peaks Volatile data is generally not very good for caching Whenever data changes the cache must be invalidated and depending on the caching strategy we are using this can be a costly operation Another type of data that is not benefited by caching is data that is fast to retrieve Caching those elements will introduce additional roundtrips while filling the cache and inevitably increase the required memory The benefit of caching these elements might event not show the expected results making them not worth the overhead Cache Types In memory CacheAn in memory cache is a chunk of RAM that is used for the temporary storage of data Since accessing RAM is significantly faster than accessing other media like hard disk drives or networks caching helps applications run faster due to faster access to data Memory caching works by first setting aside a portion of RAM to be used as the cache As an application tries to read data typically from a data storage system like a database it checks to see if the desired record already exists in the cache If it does then the application will read the data from the cache thus eliminating the slower access to the database If the desired record is not in the cache then the application reads the record from the source When it retrieves that data it also writes the data to the cache so that when the application needs that same data in the future it can quickly get it from the cache One broad use case for memory caching is to accelerate database applications especially those that perform many database reads By replacing a portion of database reads with reads from the cache applications can remove latency that arises from frequent database roundtrips This use case is typically found in environments where a high volume of data access is seen like in a high traffic website that features dynamic content from a database Another use case involves query acceleration in which the results of a complex query to a database are stored in the cache Complex queries running operations such as grouping and order can take a significant amount of time to complete If queries are run repeatedly as is the case in a business intelligence BI dashboard accessed by many users storing results in a cache would enable greater responsiveness in those dashboards Distributed CacheA distributed cache is a system that pools together the RAM of multiple networked computers into a single in memory data store used as a cache to provide fast access to data While most caches exist traditionally in one physical component be it a server or hardware component a distributed cache can grow beyond the physical limitations of a single machine by linking multiple computers for larger capacity and processing power A distributed cache pools the RAM of multiple computers into a single in memory data store used as a data cache to provide fast access to data Distributed caches are especially useful in environments with high data volume and load The distributed architecture allows incremental scaling by adding more hardware to the cluster allowing the cache to grow in step with the data growth There are several use cases for which an application may include a distributed cache as part of its architecture Application acceleration Most applications rely on disk based databases either directly or indirectly and can t always meet today s increasingly demanding requirements By caching the most frequently accessed data in a distributed cache we can dramatically reduce the bottleneck of disk based systems Storing session data A site may store user session data in a cache as inputs for a multitude of operations such as shopping carts and recommendations With a distributed cache we can have a large number of concurrent web sessions that can be accessed by any server in the system This allows us to load balance web traffic to several servers and not lose sessions should any application server fail Extreme scaling Some applications request significant volumes of data By leveraging more resources across multiple machines a distributed cache can answer those requests Caching Data Access StrategiesWhen we are caching data we can choose from a variety of caching strategies that we can implement including proactive and reactive approaches The patterns we choose to implement should be directly related to our caching and application objectives Cache Aside Lazy Loading Cache aside is perhaps the most commonly used caching approach This strategy dictates that the cache must sit on the side and the application will directly talk to both the cache and the database In this strategy when the application requires some data it will first query the cache If the cache contains the element we have a cache hit and the cache will return the data to the application If the data is not present in the cache we have a cache miss The application will now have to do some extra work The application will first have to query the database for the required data Afterwards it will return the data to the client and finally update the cache with the retrieved data Now any subsequent reads for the same data will result in a cache hit Cache aside caches are usually general purpose and work best for read heavy workloads Systems using cache aside are resilient to cache failures If there are multiple cache nodes and a node fails it will not cause a total cause of connectivity but the application might face increased latency As new cache nodes come up online and more requests are redirected to them the node will be populated with the required data with every cache miss In case of a total cache failure the application can still access the data through database requests A disadvantage of this strategy is that three network round trips are required after a cache miss First the application will need to check the cache Next the application will need to retrieve the data from the database Finally the application will need to update the cache These roundtrips can cause noticeable delays in the response Read ThroughCompared to Cache Aside Read Through moves the responsibility of getting the value from the datastore to the cache provider This strategy dictates that the cache must sit between the application and the database In this strategy when the application requires some data it will query the cache If the cache contains the element we have a cache hit and the cache will return the data to the application If the data is not present in the cache we have a cache miss The cache will first have to query the database for the required data Afterwards the cache will update itself with the required data Finally the cache will return the retrieved data to the application Now any subsequent reads for the same data will result in a cache hit Read Through caches are ideal to use in tandem with the Write Through strategy when we have data that is meant to be kept in the cache for frequent reads even though this data changes periodically This strategy is not intended to be used for all data access in an application If the system uses the cache for all data access between the database and the application a cache failure can cause a bottleneck in the application performance or outright cause an application crash since the application cannot access the database Write ThroughSimilar to Read Through but for writes Write Through moves the writing responsibility to the cache provider This strategy dictates that the cache must sit between the application and the database This strategy doesn t provide any functionality for reading data from the primary data source but handles what happens when new data or updates are issued by the application In this strategy when the application tries to update existing data or add new data to the datastore it will hit the cache This operation always results in a cache hit and the cache will either update its entries or create a new entry for the data Then the cache will update the primary data storage Finally the cache will acknowledge that the data were successfully stored On its own Write Through doesn t seem to do much if fact it introduces an extra write latency since data is written to the ache first and then to the database But when this strategy is paired with a Read Through reading strategy ensures data consistency As was the case with the Read Through strategy This strategy is not intended to be used for all data access in an application If the system uses the cache for all data access between the database and the application a cache failure can cause a bottleneck in the application performance or outright cause an application crash since the application cannot access the database Write AroundWrite Around caches have similar functionality to Write Through caches In Write Around caches the cache data will be updated only if it s already mapped into the cache and simultaneously writes the data through to the backend storage In this strategy when the application tries to add or update some data it will query the cache The cache will update the backend storage with the updated data Then if the cache contains an entry for the updated data it will update itself otherwise it will skip the data entirely This strategy protects the cache from being flooded with data that are not so frequently read while introducing minimal latency for write operations It also ensures data consistency between the cache and the main data storage Because of this it s very well suited for systems with a very high write volume of one off data such as messages from a chatting application The disadvantage of this strategy is that recently written data will always result in a cache miss and so a higher latency since data can only be found in the slower backend storage Write BackWrite Back works pretty similar to the Write Through strategy The main difference is that the cache does not update the main data storage synchronously but in batches after predefined time intervals In this strategy when the application adds or updates the data it communicates with the case The case will send an acknowledgement to the application After a defined time interval the cache will perform a batch query on the data storage and update all relevant data Write Back caches improve the write performance and are ideal for both read heavy and write heavy workloads Since the application writes only to the caching service it doesn t need to wait until the data are written to the underlying data source thus improving performance Also because all reading and writing are performed on the cache the application is insulated from database failures If the database fails queued items can still be accessed This strategy also introduces some problems that need to be addressed Considering that this strategy reads and writes to the cache first there is only eventual consistency between the cache and the main data storage If the main data storage is shared with other applications there is always the danger that other applications will get stale data if their read operations occur between batch actions Also there is no way of knowing whether cache updates will conflict with other external updates This has to be handled manually or heuristically Eviction PoliciesEviction policies allow the cache to ensure that its size doesn t exceed the maximum limit To achieve this existing elements are removed from a cache depending on the eviction policy but it can be customized as per application requirements A caching solution may be compatible with different eviction policies but before choosing a caching strategy it s good to have an idea of what eviction policies the application might need Least Recently Used LRU One of the most used strategies is Least Recently Used The Least Recently Used eviction policy removes values that were last used most far back in terms of time To do the analysis each record in the cache keeps track of its last access timestamp that can be compared to other records to find the last least recently used item Least Frequently Used LFU The Least Frequently Used eviction strategy removes values that are accessed the least amount of times To do the analysis each record keeps track of its accesses using a counter which is increment only This counter can then be compared to those of other records to find the least frequently used element Most Recently Used MRU The Most Recently Used eviction policy removes values that were last used most recently in terms of time To do the analysis each record keeps track of its last access timestamp that can be compared to other records to find the most recently used element Most Frequently Used MFU The Most Frequently Used eviction strategy removes values that are accessed the most amount of times To do the analysis each record keeps track of its accesses using a counter which is increment only This counter can then be compared to those records to find the most frequently used element Least Time To Live LTTL The Least Time To Live eviction policy removes values that have the least amount of time in their TTL field To do this analysis each record keeps track of its TTL which is assigned when it s added to the cache and decrements it at specific time intervals The field can then be compared to those of other records to find the item that lived the longest in the cache RandomThe Random eviction policy removes values randomly This policy does not respect the insertion order of the items in the cache or how frequently an item is accessed This policy can be used when we have cyclic access and all elements are scanned continuously or we expect the distribution to be uniform Real Life Caching Solutions MemcachedMemcached is a general purpose distributed memory caching system It is often used on dynamic database driven websites to reduce the number of times an external data source must be read Memcached is free and open sourced licensed under the Revised BSD license making it a very low cost solution The system is designed as a simple key value store Memcached does not understand what the application is saving it can store strings and objects as values while the keys must always be stored as strings In a distributed setting Memcached nodes don t interact with each other because the system does not provide any synchronization or replication functionality Thus the client has to decide which node has to access a particular dataset Notable Memcached Users include YouTube Reddit Twitter and Wikipedia LimitationsMemcached does not provide any persistence for the cache entries so with every crash or restart the cache needs to warm up again Another limitation is the size limit of values The values per key have to be up to MB per key This means that large objects or data sets may take more space and have to be fragmented in different cache slots Moreover objects must be serialized before being stored in the cache increasing latency for reading writing operations RedisRedis Remote Dictionary Server is an in memory data structure store used as a distributed in memory key value database cache and message broker Redis supports several data structures namely lists sets sorted sets and strings natively It also supports range queries hyperloglogs and geospatial indices Redis typically holds the whole dataset in memory but can be configured to persist its data through two different methods The first method is through snapshotting where the dataset is asynchronously transferred from memory to disk at regular intervals as a binary dump The second method is journaling where a record of each operation that modifies the dataset is added to an append only file in a background process By default Redis writes data to a file system at least every seconds with more or less robust options available if needed In the case of a complete system failure on default settings only a few seconds of data would be lost Redis also supports master replica replication Data from any Redis server can be replicated to any number of replicas Redis also provides a publish subscribe feature so a client of a replica may subscribe to a channel and receive a full feed of messages published to the master LimitationsIn a distributed environment Redis shards data based on the hash slots assigned to each master If any master goes down data to be written on this slot will be lost Moreover failovers are not supported unless the master has at least one slave Since Redis stores the data in a large hash table in memory it requires a large amount of RAM AerospikeAerospike is a flash memory and in memory open source distributed key value NoSQL database management system One of the most important selling points of Aerospike is that supports a hybrid memory model this means that if RAM is maxed out other suitable flash drives such as SSDs NVMes etc can be used as an alternative Aerospike uses flash drives to scale vertically Generally the IOPS Input Output Per Second keeps on increasing SSDs can store orders of magnitude more data per node than DRAM and NVMe drives can now perform up to K IOPS per drive Aerospike exploits these capabilities it can perform millions of operations per second with a sub millisecond latency all the time HazelcastHazelcast is an open source in memory data grid based on Java In a Hazelcast grid data is evenly distributed among the nodes of a cluster allowing for horizontal scaling of processing and available storage Backups are also distributed among nodes to protect against failure or any single node Hazelcast can run on premise in the cloud and Docker containers Hazelcast offers integration for multiple cloud configurations and deployment technologies including Apache jclouds Consul Eureka Kubernetes and Zookeeper Hazelcast can also enable cloud based or on premises nodes to auto discover each other Final ThoughtsIn this post we have discussed what cache is and what are the benefits of caching We also examined what are in memory and distributed caches We reviewed the most common caching strategies and we discussed what are the most popular eviction strategies Finally we reviewed some caching providers available to us It should now be a little more clear that choosing a caching service is not only a decision between big names or familiarity but it s more of the application s use cases data access patterns infrastructure requirements availability and volume of data among other things It s up to the engineers how much consideration they want to have before they choose something ーit s normal behaviour that people choose a technology with which they are already familiar but knowing all of these parameters for sure helps us make better design decisions	2022-08-18 09:09:00
海外TECH	Engadget	Dodge says its all-electric Charger concept is as loud as gas-powered muscle cars	https://www.engadget.com/dodge-all-electric-charger-concept-092156218.html?src=rss	Dodge says its all electric Charger concept is as loud as gas powered muscle carsWhen Dodge CEO Tim Kuniskis first talked about releasing an quot American eMuscle quot last year he said the company s vehicle will quot tear up the streets not the planet quot Now the Stellantis brand has revealed what Kuniskis meant by that It has introduced the Dodge Charger Daytona SRT concept which looks like a futuristic take on its gas powered Challenger and Charger muscle cars While it s still just a concept at this point and could change tremendously by the time it s released a spokesperson told TechCrunch that quot it is very close to production quot The two door electric Dodge Charger will be powered by the new V Banshee propulsion system In its announcement Dodge says the Banshee is more powerful than the engine of a Hellcat which is already a high performance variant of the Challenger And unlike other electric vehicles that barely make a sound the all electric Charger was designed to be loud just like its gas powered counterparts The company actually put an exhaust on the vehicle even though it doesn t need one and the only thing it emits is sound quot The Charger Daytona SRT Concept voices a dB roar that equals the SRT Hellcat quot Dodge writes in its announcement That s made possible by pushing the EV s sounds through an amplifier and tuning chamber You can hear what it sounds like in the video below starting at the mark Outside the vehicle features a familiar design with modern tweaks that make it more aerodynamic The quot R Wing quot at the front end for instance has a pass through form factor that allows air to flow through and enhance downforce Inside you ll find modern amenities including a inch center screen an x inch Head up Display that shows additional vehicle information and a PowerShot button on the steering wheel that gives the vehicle a burst of acceleration Dodge has yet to announce pricing for the Charger Daytona but the company previously said that it s targeting a release date for its first American eMuscle By the time it arrives the brand would ve already discontinued its gas powered Challenger and Charger muscle cars Kuniskis said in a statement quot Dodge is about muscle attitude and performance and the brand carries that chip on its shoulder and into the BEV segment through a concept loaded with patents innovations and pertformance features that embody the electrified muscle of tomorrow The Charger Daytona SRT Concept can do more than run the car show circuit it can run a blazing quarter mile And when it comes to product cycles it outruns Darwin Charger Daytona does more than define where Dodge is headed it will redefine American muscle in the process quot	2022-08-18 09:21:56
海外科学	NYT > Science	U.S. Ship Sunk by Germans in 1917 Is Found Off English Coast	https://www.nytimes.com/2022/08/18/world/europe/us-navy-destroyer-shipwreck.html	action	2022-08-18 09:56:23
医療系	医療介護 CBnews	東京都のコロナ入院患者数、過去最多を更新-検査陽性率「極めて高い値で推移」	https://www.cbnews.jp/news/entry/20220818180512	入院患者	2022-08-18 18:10:00
ニュース	@日本経済新聞 電子版	三菱地所、丸ビル・新丸ビルを改装　大規模実施は初 https://t.co/xnN9zWXrFx	https://twitter.com/nikkei/statuses/1560199653894737920	三菱地所	2022-08-18 09:39:19
ニュース	@日本経済新聞 電子版	通信システムにサイバーセキュリティー対策をした防衛関連企業への税優遇を政府が検討。中国やロシアからのサイバー攻撃を念頭に、防衛産業の機密漏洩対策を後押し。2023年の通常国会へ関連法案提出を目指します。 #日経イブニングスクープ https://t.co/Eem7vO0J5L	https://twitter.com/nikkei/statuses/1560197373598507008	通信システムにサイバーセキュリティー対策をした防衛関連企業への税優遇を政府が検討。	2022-08-18 09:30:15
ニュース	@日本経済新聞 電子版	大阪桐蔭、春夏連覇ならず　下関国際が甲子園初の4強 https://t.co/nF5QA6gXcg	https://twitter.com/nikkei/statuses/1560196112132509697	大阪桐蔭	2022-08-18 09:25:14
ニュース	@日本経済新聞 電子版	英国2桁インフレ・入社前の体験希望・八神純子さん https://t.co/JdVVAOX6QO	https://twitter.com/nikkei/statuses/1560194233973501952	八神純子	2022-08-18 09:17:47
ニュース	@日本経済新聞 電子版	国内コロナワクチン接種、3回完了は8082万人　4回目は1978万人 #日経_チャートで見る日本の接種状況 #日経ビジュアルデータ https://t.co/bJ6EKIHK0J	https://twitter.com/nikkei/statuses/1560193551778152448	状況	2022-08-18 09:15:04
ニュース	@日本経済新聞 電子版	森英恵さん「先頭走る道しるべ」　コシノジュンコさん https://t.co/dLo6EOCtWh	https://twitter.com/nikkei/statuses/1560190192581222400	道しるべ	2022-08-18 09:01:43
ニュース	@日本経済新聞 電子版	サイバー対策に税優遇　政府、防衛企業の機密保護へ新法 【日経イブニングスクープ】 https://t.co/nCjxQubq0F	https://twitter.com/nikkei/statuses/1560190191352283138	防衛	2022-08-18 09:01:43
海外ニュース	Japan Times latest articles	PGA players rally around Tiger Woods in fight against LIV Golf	https://www.japantimes.co.jp/sports/2022/08/18/more-sports/golf/tiger-woods-pga-liv/	mcilroy	2022-08-18 18:18:55
海外ニュース	Japan Times latest articles	Borna Coric spoils Rafael Nadal’s return to Cincinnati	https://www.japantimes.co.jp/sports/2022/08/18/tennis/nadal-eliminates-cincinnati/	nadal	2022-08-18 18:18:19
海外ニュース	Japan Times latest articles	Japanese squad to host Ivy League all-star team in Japan-U.S. Dream Bowl	https://www.japantimes.co.jp/sports/2022/08/18/more-sports/football/japan-ivy-dream-bowl/	bowlthe	2022-08-18 18:11:05
ニュース	BBC News - Home	Amol Rajan to take over from Jeremy Paxman as University Challenge host	https://www.bbc.co.uk/news/entertainment-arts-62588667?at_medium=RSS&at_campaign=KARANGA	challenge	2022-08-18 09:46:51
ニュース	BBC News - Home	MP Margaret Ferrier pleads guilty to exposing public to Covid	https://www.bbc.co.uk/news/uk-scotland-62589375?at_medium=RSS&at_campaign=KARANGA	glasgow	2022-08-18 09:55:47
ニュース	BBC News - Home	Rushdie suspect 'read two pages' of Satanic Verses	https://www.bbc.co.uk/news/entertainment-arts-62588666?at_medium=RSS&at_campaign=KARANGA	salman	2022-08-18 09:08:17
ニュース	BBC News - Home	Afghanistan: Deadly blast rips through crowded Kabul mosque	https://www.bbc.co.uk/news/world-asia-62581102?at_medium=RSS&at_campaign=KARANGA	taliban	2022-08-18 09:28:04
ニュース	BBC News - Home	Bodies found in New Zealand auction suitcases were of two young children	https://www.bbc.co.uk/news/world-asia-62588994?at_medium=RSS&at_campaign=KARANGA	childrenthe	2022-08-18 09:23:34
ニュース	BBC News - Home	A-level results 2022: How were grades decided?	https://www.bbc.co.uk/news/education-58026976?at_medium=RSS&at_campaign=KARANGA	grades	2022-08-18 09:05:54
ビジネス	不景気.com	静岡の貸切バス運行「遠江観光」に破産決定、負債2億円 - 不景気com	https://www.fukeiki.com/2022/08/totoumi-kanko.html	株式会社	2022-08-18 09:49:54
ビジネス	不景気.com	富山の園芸店経営「大井種苗店」に破産決定、負債2億円 - 不景気com	https://www.fukeiki.com/2022/08/ooi-shubyoten.html	富山県富山市	2022-08-18 09:35:10
京都	烏丸経済新聞	10年目の「京まふ」開催へ　イベント支援者募集も始まる	http://karasuma.keizai.biz/headline/3674/	京都国際マンガ	2022-08-18 18:30:15
北海道	北海道新聞	縄文遺跡群やウポポイ、観光バスで巡ろう　北海道中央バスが新コース	https://www.hokkaido-np.co.jp/article/719227/	世界文化遺産	2022-08-18 18:36:00
北海道	北海道新聞	演奏、ダンス　定演沸いた　富良野高吹奏楽部	https://www.hokkaido-np.co.jp/article/719225/	吹奏楽部	2022-08-18 18:35:00
北海道	北海道新聞	１００万円詐取疑い、大工の男逮捕　札幌東署	https://www.hokkaido-np.co.jp/article/719217/	札幌市西区	2022-08-18 18:27:00
北海道	北海道新聞	東京円、１３５円台前半	https://www.hokkaido-np.co.jp/article/719223/	東京外国為替市場	2022-08-18 18:32:00
北海道	北海道新聞	神奈川２児熱中症死 母親を追送検　長女放置疑い	https://www.hokkaido-np.co.jp/article/719221/	熱中症死	2022-08-18 18:32:28
北海道	北海道新聞	「弔意の強制」国葬撤回を　宗教者団体、都内で反対会見	https://www.hokkaido-np.co.jp/article/719222/	安倍晋三	2022-08-18 18:32:00
北海道	北海道新聞	大輪ヒマワリ満開　名寄・サンピラーパーク	https://www.hokkaido-np.co.jp/article/719160/	名寄市日進	2022-08-18 18:32:15
北海道	北海道新聞	横綱の里活性化へ期待大　２０日から福島で相撲の全国中体連	https://www.hokkaido-np.co.jp/article/719220/	全国中学校体育大会	2022-08-18 18:30:00
北海道	北海道新聞	道南各地で全国中体連　ハンドボール函館で開幕、市内２選手が宣誓	https://www.hokkaido-np.co.jp/article/719219/	全国中学校体育大会	2022-08-18 18:29:00
北海道	北海道新聞	アクロバティックで華麗な動き間近で　２７日に札幌でパルクール大会	https://www.hokkaido-np.co.jp/article/719215/	障害	2022-08-18 18:26:00
北海道	北海道新聞	一流に学び、目指す音色へ　３年ぶりに若手育成「紋別音楽セミナー」　２０、２１日受講生ら無料コンサート	https://www.hokkaido-np.co.jp/article/719214/	音色	2022-08-18 18:20:00
北海道	北海道新聞	「メロン川柳」最優秀に井上さん　「血糖値検査の翌日メロン食べ」　訓子府町振興会５０周年で企画	https://www.hokkaido-np.co.jp/article/719203/	訓子府町	2022-08-18 18:13:00
北海道	北海道新聞	大阪桐蔭４―５下関国際　下関国際、九回に逆転	https://www.hokkaido-np.co.jp/article/719201/	大阪桐蔭	2022-08-18 18:11:00
北海道	北海道新聞	ＢＰ建設現場紹介する車内放送人気　ＪＲ千歳線快速エアポート　男性車掌、独自の取り組み	https://www.hokkaido-np.co.jp/article/719195/	取り組み	2022-08-18 18:07:33
北海道	北海道新聞	関電に２３９億円賠償請求　米法人など「金品受領巡り損害」	https://www.hokkaido-np.co.jp/article/719197/	福井県高浜町	2022-08-18 18:02:47
IT	週刊アスキー	440円→250円に！バーガーキングの人気「ワッパーチーズJr.」が43％オフになるお得なキャンペーン【1週間限定】	https://weekly.ascii.jp/elem/000/004/102/4102155/	特別価格	2022-08-18 18:45:00
IT	週刊アスキー	ティアック、カラオケに便利なマイク入力も備えるカセットデッキ／CDプレーヤー「AD-850-SE」8月27日発売	https://weekly.ascii.jp/elem/000/004/102/4102124/	月日	2022-08-18 18:30:00
IT	週刊アスキー	「グリザイア 戦場のバルカローレ」にてレイドイベント「盗られた夏を取り戻せ」を開催！　イベント記念ピックアップガチャも登場	https://weekly.ascii.jp/elem/000/004/102/4102140/	dmmgames	2022-08-18 18:20:00
IT	週刊アスキー	「エンジェリックリンク」リリース1周年記念のアニバーサリーイベントやキャンペーン情報を公開！	https://weekly.ascii.jp/elem/000/004/102/4102139/	dmmgames	2022-08-18 18:15:00
IT	週刊アスキー	DMM GAMES、「千年戦争アイギス」にて10連召喚チケットがGETできるイベントを開催！　高レアの帝国キャラを選べるお得なパックも販売中	https://weekly.ascii.jp/elem/000/004/102/4102135/	dmmgames	2022-08-18 18:10:00