nScreenMedia OTT multiscreen media analysis

YouTube TV DVR’s 20 Exabyte storage requirement

YouTube TV splash

YouTube TV provides a benefit no other vMVPD offers, unlimited DVR storage. It could require the service to buy and maintain 20 Exabytes of storage unless it has managed to win a license right no other vMVPD has.

YouTube TV provides unlimited DVR storage

Providing unlimited DRV storage is a significant advantage for YouTube TV. Other services are much less generous. For example, Hulu Live limits recordings to 50 hours on the basic tier, and 200 hours if you pay extra. AT&T TV Now users are limited to just 20 hours of storage. The only restriction on a YouTube TV user’s storage is the length of time a recording is kept around. According to the service’s help system:

“As long as you maintain your membership status, live TV recordings will be saved for nine months. Other programs will vary based on agreements with our content partners.”

Such generosity could be costing YouTube TV a massive amount in storage and maintenance costs unless it has won a license right no other pay TV operator has been able to get.

YouTube TV needs to store one copy of a show for each recording request

Back in 2009, Cablevision prevailed before the Supreme Court in a lawsuit brought by TV programmers regarding its remote DVR technology. The programmers said storing TV shows in the data center and allowing people to watch them remotely in their homes amounted to a rebroadcast, which Cablevision’s TV channel license did not permit. The Supreme Court did not agree, siding with Cablevision’s view that if it worked like a DVR it didn’t matter where the TTV show was stored.

However, Cablevision’s implementation kept a single copy of each show recorded for each person requesting a recording. So, if ten people recorded the ten o’clock news on ABC, the system kept ten copies of the recording. Serving everyone recording the news from one file – called shared copy – would likely have been held to be a rebroadcast, and not covered by Cablevision’s content license.

In other words, YouTube TV also needs to keep one copy of each show per request unless it has won the right to use the shared copy method from the TV programmers. If it has, it is likely the only vMVPD or MVPD to do so.

The minimum storage needed in the single-copy model

I suspected that almost all DVR users run with the DVR disk effectively full, letting the device manage the space. To check this, I asked the DVR experts, TiVo. Charles Dawes, Senior Director, International Marketing at TiVo, told me:

“Yes – your hypothesis is correct. Almost all TiVo users have, over time, a disk that is running at near full capacity, and they rely on TiVo’s software to actively manage their content for them.”

Many TiVo models have a terabyte of storage or more. If each of the million-plus YouTube TV users are using a terabyte of disk space, the company would need an Exabyte of storage.[1] However, they are probably using much more. People are limited in their storage needs by the size of the hard disk in their DVR. With YouTube TV, there is no limit. So, how much storage are people really using?

A better estimate of storage requirements for YouTube TV’s network DVR

Many shows in syndication cycle through all the seasons in a relatively short time. For example, Charmed plays in the mornings on TNT, delivering about 23 episodes a week. The channel cycles through every episode of each of the eight seasons in about eight weeks. Similarly, TBS cycles through every episode of the 12 seasons of Big Bang Theory in about 22 weeks. Assuming all the episodes are captured in HD, it takes 300 Gigabytes of storage to record Charmed.

On YouTube TV, if a user favorites five syndicated shows, within three months all the recorded episodes will likely occupy 1.5 Terabytes of storage. Moreover, if each family member has their own favorite five shows, each subscriber could be using ten terabytes. As well, the 9-month limit doesn’t reduce the storage requirement, since the syndicating channels cycle through the episodes within a few months.

Recording 5 syndicated shows might not sound realistic. However, there is no incremental cost to record a show. All a user must do is favorite it, and all the episodes will appear over time. I have eight or more syndicated shows in my YouTube TV DVR library, and I hardly ever watch them!

There are also all the football games, news, and current shows that people will record and never bother to erase. This “transient” load could double the disk storage requirement again. In other words, the per-subscriber storage requirement could easily be 20 terabytes or more!

YouTube TV needs at least 20 Exabytes of storage to handle the unlimited DVR requirements of its one million customers. 20 Exabytes is about 2% of all the hard disk storage space that will be shipped worldwide in 2019.[2]

The incredible expense required to buy and maintain that much storage is why every other vMVPD puts severe limits on the number of recordings its DVR users can make.

Shared copy slashes storage requirements

Of course, if YouTube TV is using shared copy, not single copy, the storage requirement would be dramatically different. All the service would need to do is record everything broadcast on every channel it carries. Then when someone requests a recording, YouTube TV simply uses the single recording it has already made. Over nine months, it would need at most 50 Petabytes or about 400-times less than single copy.

Why it matters

YouTube TV offers unlimited recordings to its subscribers and makes it very easy to record entire seasons of shows.

Using the single copy method of storage, YouTube TV needs 20 Exabytes or more of hard disk storage.

Using the shared copy method, the company needs 400 times less storage.

[1] One hour of HDTV requires about 1.7 Gigabytes of storage.

[2] Thomas Coughlin, Digital Storage Technology Newsletter, Coughlin Associates, August 2019, p88


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.