media cache - for files store on the same machine ?

Wowza Streaming Engine
1

I wonder why Media Cache will help for files store on the same machine of Wowza? It just does the same thing - get files from disk and stream ?? So why is it faster ? Is there any extra processes here ?

2

MediaCache can request content from any web server, but in order for MediaCache to provide significant benefits the local storage used by MediaCache should have extremely fast seek and I/O access speeds and have an appropriate amount of space.

MediaCache can store any number of assets as long as the cache specified has the appropriate amount of space.

In order to cache an asset the entire asset needs to be able to fit in the cache location, if it will not fit then there is no benefit to Wowza, MediaCache source or the end user.

Any content cached is made available for playback by any client so in order to service any number of clients the cache speed needs to exceed that of the client requests.

It is important to note seek time and read throughput. In most cases a standard ‘disk’ is not sufficient to be used as a cache location so consideration of multiple disks using RAID or SSD should be made.

I hope this answers your question.

Salvadore

3

Hi,

If you content is already stored on the same local disk, then Media Cache won’t bring any improvements.

Media Cache will help you if you have a multiple server setup, probably in a load balanced architecture, where several Wowza Streaming Engine servers are configured to deliver video on demand streams and the video files are stored on a network storage drive, or a remote web server. In this case, it is not efficient to store all your video files on each of the Wowza servers from your streaming platform. You can store the videos in a central location, and have the Wowza servers, using the Media Cache feature, retrieve and cache locally and deliver only the video on demand files that are being requested by the playback clients.

Zoran

4

Hi,

Media Cache is improving the delivery from Wowza to the playback clients. It is requesting one the media file from the content storage location once, caching it locally, and delivering it to the playback clients as soon as it is requested.

Zoran

5

Thank for your info but that seems not aim at the question. The question is why Media Cache will help for files store on the same machine of Wowza? It just does the same thing without using Media Cache- get files from disk and stream ?? So why is it faster ?

What if I do not use Media Cache, it looks like it is the same - because it gets data from a location on disk ?

6

Thank for your answers about local storage. Just another question in the case of remote storage. The time it takes to transfer files from network storage device to Wowza probably not much ? It is still fast in this case ? Media Cache helps but does it help significantly here in the case that the speed of transferring files from network storage device to Wowza is high ?

7

Content is not always stored on the same machine, or on the same disk(s) of the same machine. In these cases you get a local, dynamic, high-speed cache, which does make a difference.