Shulou(Shulou.com)06/01 Report--

This article mainly shows you "what is the use of ceph-immmutable-object-cache", the content is easy to understand, clear, hope to help you solve your doubts, the following let the editor lead you to study and learn "what is the use of ceph-immmutable-object-cache" this article?

I. brief introduction

Currently, the official ceph-immmutable-object-cache daemon is responsible for caching content to the local cache directory. For better performance, it is recommended to use SSD as the underlying storage medium.

II. IO process

The ceph-immmutable-object-cache daemon starts to initialize, listens on the local domain socket and waits for a connection from the librbd client.

The client librbd connects to the cache daemon through the domain socket and registers with the cache daemon.

When the client librbd reads, it requests to the cache daemon to find it. If not found, the daemon reads the RADOS object directly and writes to the local cache directory. Otherwise, find the update LRU and move it to the header.

If the return tells the client that it is not cached, the client librbd gets the information directly from the rados. (the next time the librbd will be obtained directly from the local)

III. Strategy

MAP information maintains filename and Entry information.

The LRU linked list maintains Entry information to ensure that the capacity reaches the threshold to eliminate the cache.

Entry information, maintenance of maximum capacity, capacity water level, maximum ops.

IV. Storage format

Filename: pool_nspace + ":" + std::to_string (pool_id) + ":" + std::to_string (snap_id) + ":" + oid

Cache_file_dir: ceph_crc32c (0, file_name, length)% 100

Key: m_cache_root_dir + cache_file_dir + cache_file_name

Val:object_name

The above is all the content of this article "what's the use of ceph-immmutable-object-cache?" Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.