Setting Up Local Media Caching & SQL Log Item Cue Caching

Modified on Tue, 24 Sep at 12:56 PM

Local Media Sync

This article covers the process of setting up local media caching in Myriad 5 Playout. Once setup, this option enables the Local Caching Application which will maintain a copy of some or all of your Media on a designated local hard drive. Whenever Myriad 5 Playout needs to play a Media Item, it will first check the local cache location and use this if present. If the needed Media Item is not available in the local cache location then it will use the network file stored in the central data location. This configuration can improve performance and reduce playback issues caused by slow or inconsistent networks.

WARNING: If your network is unstable or performing badly, you should fix your network first as local caching will only mask issues that may (and probably will) cause issues elsewhere in your system!

Before you get started, you will need to consider the following:

Which Myriad 5 workstations you want to enable local sync on.
What content do you want to include in the local cache (all content or just certain types like Songs and Jingles).
Do you have enough free disk space on the PC to enable the storage of this content.

To enable local sync, follow these steps:

Go the a PC you want to enable local caching on.
Run Myriad Playout (v5.28 or higher).
Go to Settings Menu > Applications Settings > Data Locations Tab
On the Data Locations tab, tick the Also cache data files onto the local hard drive option.
Set the location to use for the locally cached files using the browse button.
When you are done, click on OK. You will now need to Restart Myriad Playout in order for these changes to take effect.

Myriad Playout is now configured to use local caching on this PC but you still need to add a few more settings to the Local Sync application so it know what Media Items you want to cache on to the local storage.

Once you have restarted Myriad, expand your sys-tray and you will see a new Local Sync application is running in a minimised state.

Click on the icon to open Local Sync.

To configure the Media Items you want to synchronise to your local cache, follow these steps:

Click on Syncing Menu > Edit Media Sync.
This will open the Media Sync Settings window which is used to set the Media Ranges and / or Media Types you want to include in the Local Sync process.
Slide the Automatically Start option to Yes.
When deciding what content to sync to the local cache, you can use with a Range (ie from 1 to 10,0000) or a Media Type (ie Links or Songs) or a combination of both. In this example, we are going to add a Range of Media Items what will cover our Songs (they are between 10,000 and 15,000 in this example) plus we will also add Media Item Types for Links.

To add a new Range or Type to sync, click on the New Sync button.

You can then select whether you want to sync a Range from the Media Wall or a particular Media Item Type.

Let's add a range first. Select Media Range from the Sync Type option and then type in the Media Range you want to sync.

In the example above, Local Sync will copy all Media Items between 10,000 and 15,000 to our local cache. Click on OK to add the settings.

Now lets a add in all Media Items that have Media Type set to Links.

Click on the New Sync button again but this time select Media Item Type from the Sync Type options and then select the Link type from the Item Type option.

As you can see, both the Range (10,000 to 15,000) and the Media Type (Link) has been added to our Local Sync settings.
The final section of the Media Sync Settings window is concerned with what to do with a locally cached Media Item when it is deleted from the central Data Location:

The first option (Keep the local cached copy for disaster recovery purposes) will not delete the cached copy of a Media Item when the the matching Media Item on your central Media Wall is deleted. This means you could recover the audio from this local cache should it be accidently deleted from the central Media Wall. This option is good for disaster recovery but could result in using a lot of additional disk space on your local hard drive.

The second option (Mark the local cached copy to be deleted after 4 days) will set the system to automatically deleted the cached media file after 4 days giving you that time to recover it if required. After 4 days the file will be deleted freeing the associated disks space.
When you have added all your Sync Settings, click on the OK button.

The first time you enable this, you will see that the system will immediately start to copy Media Items to the selected local cache location. This may take some time to complete. You can minimise the application and it will return to the sys-tray.

Once complete, Myriad Playout will always try to use a local sync file before it uses a network file.

Every time you add new content or edit content within a synchronised Range or Media Type, the resulting changes will be replicated to the local cache shortly after.

This will increase performance in Myriad Playout (as it is working on local audio files) and can also work around slow or unreliable networks. If you are experiencing network speed or reliability issues, we strongly recommend you address these issues rather than using Local Caching as a 'plaster' to hid the network issues.

For further assistance with addressing network issues see - Network Troubleshooting – Broadcast Radio Help

Increasing SQL Cue Caching

Local caching of audio files can help Myriad 5 Playout to continue to play audio in the event of a network or server issue but unless Myriad 5 Playout knows what it should be playing, it will not be able to play Media Items even if they are in the local cache.

Luckily, there is a setting you can use to increase the amount of Log Items the system 'look' ahead in the Log and keep these in local memory. If Myriad 5 Playout temporarily looses contact with the SQL server, it will fall back on this list and continue to play items from the Log until the SQL connection is re-established or it runs out of it's cached list of items to play!

To adjust this setting click on Settings Menu > Station Settings > Scheduled Log Tab.

The setting we are interested in is Additional number of Log Items ahead to cache.

This is how many additional items are ALSO held in memory in the engine ready to be executed without a round trip to the database, but are not being shown in the Dashboard.

The higher this number is set, then the longer Myriad Playout can run without the SQL server even being available.

For example, if you had a problem with the Microsoft SQL Server software, such that it was no longer responding to requests for information, Myriad would be able to carry on for this many items before it could no longer operate.

The downside to setting this number very high is that it means that Myriad has to watch much more of the log for any changes, so can slow Myriad down slightly.

In the screen shot above, this has been set to to 50 items, and for our fictional station, let us assume that covers the next 2 hours worth of log items in the Scheduled Log. Therefore ANY changes to ANY of those 45 items will result in Myriad having to check and update the log playback engine.

By combining this setting with Local Cache Media Items, you can configure Myriad 5 Playout to be able to continue to operate on a PC even if the central Data Location is not available for a short time. This will allow your re-start a server or investigate a network fault.

Important Note: The measures above are designed to keep you 'on air' during a short network outage. The SQL database includes far more than just a list of Log Items so after only a few minutes loss of connectivity to the SQL server, you will start to see error messages in Myriad telling you that non-critical systems are unable to connect to the SQL server.

However, your core audio will continue to play as long as the content is in the Local Cache and you do not run out of cached Log items.