Does downloading make a difference?

PART 2 of our testing on the PlayStation 4 storage systems, with the stock hard drive, an SSHD hybrid and an SSD. Previously, we compared performance based on Blu-ray based installations though today we add downloaded titles from PSN to the mix. Be sure you read PART 1, PlayStation 4 (PS4) HDD, SSHD and SSD Performance Testing. This isof our testing on the PlayStation 4 storage systems, with the stock hard drive, an SSHD hybrid and an SSD. Previously, we compared performance based on Blu-ray based installations though today we add downloaded titles from PSN to the mix. Be sure you read

I posted a story earlier this week that looked at the performance of the new PS4 when used with three different 2.5-in storage options: the stock 500GB hard drive, a 1TB hybrid SSHD and a 240GB SSD. The results were fairly interesting (and got a good bit of attention) but some readers wanted more data. In particular, many asked how things might change if you went the full digital route and purchased games straight from the Sony's PlayStation Network. I also will compare boot times for each of the tested storage devices.

You should definitely check out the previous article if you missed it. It not only goes through the performance comparison but also details how to change the hard drive on the PS4 from the physical procedure to the software steps necessary. The article also details the options we selected for our benchmarking.

Today I purchased a copy of Assassin's Creed IV from the PSN store (you're welcome Ubisoft) and got to testing. The process was the same: start the game then load the first save spot. Again, each test was run three times and the averages were reported. The PS4 was restarted between each run.

The top section of results is the same that was presented earlier – average load times for AC IV when the game is installed from the Blu-ray. The second set is new and includes average load times fro AC IV after the installation from the PlayStation Network; no disc was in the drive during testing.

First, the load times across the board were faster for PSN installs than they were for Blu-ray installs, which actually kind of boggles the mind. It seems obvious that read from the optical drive is taking some time even when Sony is installing the necessary content on the hard drive itself. Some kind of authentication is likely taking place in a pattern (or even continuously) to make sure the disc hasn't been removed. Even with the stock hard drive we see load times drop from 35 seconds to 28 seconds, a decrease of nearly 20%.

Both the SSHD and the SSD results decrease as well though: 20% and 14% respectively. Keep in mind that the SSHD load times are SLOWER for the first run but decrease in the 2nd and 3rd run as more of the data becomes cached.

If you read the previous article, you should remember that we perceived a see-saw pattern of load times with the AC IV test when installed from Blu-ray drive. That no longer seems to take place with the PSN downloaded version of the game. With the same SSHD at work, the load times were consistent once the data was cached. Very little difference was seen between runs 3-7. It would appear that some of the disc read times might be randomly inserted, causing the variance we saw with the disc-installed setup.

Finally, users were asking about boot times with the three storage options so I did some quick testing. Clearly the SSD is the fastest of the three once again getting to the menu 5.5 seconds faster than the stock drive (nearly 25%). The Seagate SSHD does have better performance as well but carefully consider if those 5 seconds you save are worth it to you.

Downloading versus Blu-ray Installing

It surprised me, but there is definitely a performance advantage to installing your games from the PSN (and going all digital) compared to installing from a Blu-ray. Obviously the PS4 is doing some kind of checks with the disc in the drive on a semi-regular basis and not simply checking it once during game load time. It it were, and if the data downloaded were the same as the data copied from the disc, then load times should be identical; they aren't.

Potential SSHD Issues

Even though we saw a lot of the oscillation of load time performance go away with the downloaded version of Assassin's Creed IV, there are still some obvious concerns with using a hybrid HDD + SSD solution as they currently exist. First, though our repeated loading tests show improvements in performance, keep in mind we were loading the same level over and over, not loading new levels or different ones. I would imagine that frequent changing of games (starting up a game of NBA 2K14 for example) would start to throw the cache for loop and the performance advantages would come and go depending on your particular gaming habits.

A solution to this (or at least a reduction to the ailment) would be to increase the size of the flash on the drive. Current Seagate options are limited to 8GB of flash. Increasing that to 32GB would likely allow a lot more caching to occur and make your gaming experiences better overall. I'm actually surprised neither Sony or Microsoft thought of this option (or at least failed to act on those good insights) for their storage implementations.

TRIM Support?

Several people have asked about using SSDs with the PS4 without knowing if TRIM is supported on the platform. While I still don't know for sure if it is, a quick chat with Allyn, our storage guru, was a bit more reassuring.

I don't think the installation process is going to be doing random writes to an SSD, and sequential writes do not impede performance over time. Remember, it is the sequential write process that actually can restore an SSD to full read/write performance without TRIM in use.

Essentially, because of the installation process going on with PSN installed games, it could be "fixing" any issues that the SSD would suffer without a TRIM-aware operating system anyway. Random writes, the action that can actually fragment the flash, would be pretty minimal in a console environment with exception of saved games. Even captures of video content on the PS4 would long, extended (and sequential) writes.

Why is there no 7200 RPM drive tested?

Honestly, I just couldn't find a 500GB or 1TB 7200 RPM laptop drive in stock today, though, again talking with Allyn, we decided that if we had one to test, the performance would be much closer to that of the stock drive than the SSHD.

Closing Thoughts

My testing testing of the storage performance of the PS4 has been interesting but is no means complete or all-encompassing. We'll likely be trying out some new games in the coming days, both digital and disc-based, but until then…anyone want to buy a Blu-ray copy of Assassin's Creed IV?

This is PART 2 of our testing on the PlayStation 4 storage systems, with the stock hard drive, an SSHD hybrid and an SSD. Previously, we compared performance based on Blu-ray based installations though today we add downloaded titles from PSN to the mix. Be sure you read PART 1, PlayStation 4 (PS4) HDD, SSHD and SSD Performance Testing.