不爲也 比不能也

Here are some great slides from our Core Elasticsearch: Operations course that help explain the concept. We'd recommend that you take the full course to understand this even better, but I'll provide an overview from our training here:다음은 Core Elasticsearch: Operations 과정(개념을 설명하는)에서 제공하는 몇 개의 멋진 slide이다. 이 내용을 더 잘 이해하기 위해서는 전체 과정을 수강하는 것이 좋겠지만, 여기에서 과정의 개요를 제공한다.Shard allocation is the process o..

As the project manager of stagemonitor, an open source performance monitoring tool, I've recently been looking for a database to replace the cool-but-aging Graphite Time Series DataBase (TSDB) as the backend. TSDBs are specialised packages for storing (performance) metric data, like the response time of your app or the CPU utilisation of a server. Ultimately, we were looking for a datastore that..

UPDATE: This article refers to our hosted Elasticsearch offering by an older name, Found. Please note that Found is now known as Elastic Cloud.이 게시물은 기존에 Found라는 이름으로 제공된 Elasticsearch 서비스에 관한 것이다. Found은 이제 Elasticsearch Cloud로 알려져 있다.The previous article in this series, Elasticsearch from the Bottom Up, covered essential data structures within a single shard. In this article, we will look at t..

UPDATE: This article refers to our hosted Elasticsearch offering by an older name, Found. Please note that Found is now known as Elastic Cloud.이 게시물은 기존에 Found라는 이름으로 제공된 Elasticsearch 서비스에 관한 것이다. Found은 이제 Elasticsearch Cloud로 알려져 있다.In this article series, we look at Elasticsearch from a new perspective. We'll start at the "bottom" (or close enough!) of the many abstraction levels, and gradua..

Closing / deleting indices while running snapshoteditIn previous versions of Elasticsearch, closing or deleting an index during a full snapshot would make the snapshot fail. In 5.0, the close/delete index request will fail instead. The behavior for partial snapshots remains unchanged: Closing or deleting an index during a partial snapshot is still possible. The snapshot result is then marked as ..

In Life Inside a Cluster, we introduced the shard, and described it as a low-level worker unit. But what exactly is a shard and how does it work? In this chapter, we answer these questions:Life Inside a Cluster에서, low-level worker unit 이라 묘사된, shard를 소개했었다. 이 장에서는 shard가 정확이 무엇이고, shard가 동작하는 방법에 대한 설명을 하도록 하겠다.Why is search near real-time?왜 검색은 실시간에 가까운가?Why are document CRUD (create-read-updat..

Without an fsync to flush data in the filesystem cache to disk, we cannot be sure that the data will still be there after a power failure, or even after exiting the application normally. For Elasticsearch to be reliable, it needs to ensure that changes are persisted to disk.fsync 없이, filesystem cache에서 디스크로, 데이터를 flush하면, 정전 후에 또는 응용프로그램이 정상적으로 종료된 후에, 데이터가 거기 있다고 확신할 수 없다. 신뢰할 수 있는 Elasticsearc..

With the automatic refresh process creating a new segment every second, it doesn’t take long for the number of segments to explode. Having too many segments is a problem. Each segment consumes file handles, memory, and CPU cycles. More important, every search request has to check every segment in turn; the more segments there are, the slower the search will be.매초마다 자동 refresh 프로세스가 새로운 segment를 ..

There will come a time when you need to perform a rolling restart of your cluster—keeping the cluster online and operational, but taking nodes offline one at a time.cluster를 차례대로 재 시작(cluster는 온라인이고 동작을 하는 상태로 유지하면서, node를 차례로 오프라인으로 하는)해야 할 경우가 있을 것이다.The common reason is either an Elasticsearch version upgrade, or some kind of maintenance on the server itself (such as an OS update, or hardware..