I found out what was freezing Watch Dogs: Legion (can see it in task manager)

g67575

g67575

g67575

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I left task manager running on my 2nd monitor and I noticed that when the game freezes, the active time on the SSD I installed the game on reaches 100% and doesn't return to 'normal' until the game resumes again (usually takes about 30 seconds). When the freezing issue happens, the game is heavily writing to the page file and swap file.

The read access time of my BX500 Crucial 2TB SSD is apparently approx. 220 microseconds, so not the best. Other performance stats of the drive seem fine though.

The latest consoles use NVME drives, which have much lower access times (and we know Ubisoft doesn't put much time and effort into PC ports).

As far as I can tell, the VRAM was not a factor in this freezing, except that higher texture settings result in more data being read by the SSD.
 
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Task manager doesnt tell you anything about access times. Your SSD will be closer to 0.1ms. 220ms is mechanical drive levels of delay.

Disk usage in the task manager shows disk utilisation. If it's hitting 100% then there's a throughput bottlenecked somewhere. The BX500 has no dram cache so that could be the cause? looking at some reaviews it is quite limited in certain situations compared to drives with onboard cache, i wouldnt be suprised if Watch Dogs is hitting the drive in a similar mannor to the tests which the BX500 doesnt do too well in. Just speculation, i'd have to look in more detail.

g67575 said:
The latest consoles use NVME drives, which have much lower access times (and we know Ubisoft doesn't put much effort into PC ports).
Click to expand...

Again, access times are broadly the same - ie, very very fast. It's broadly burst throughput that puts NVME ahead, and that's because of the limitations of SATA. Things like random access performance and sustained throughput relies much more heavily on the architecture of the drive itself and cache is a big part of that.
 
The BX500 has no dram cache so HDD or worse seek times are to be expected when the drive has to find out where the data is stored. I used to have a dramless drive and GTA V used to stutter super hard, in Modern Warfare 2019 guns and characters wouldn't load for a good 30 seconds into a match. Neither of these things happened on my HDD.
 
g67575 said:
Oops, I've edited it now, it should have said active time.

Access times (Read) on NVME SSDs do appear to be significantly lower, here is an example:

https://www.elinfor.com/article/S/S/SSD (2).png
Click to expand...

If you are comparing that to what you are reading in the task manager then they aren't the same thing. Apples and oranges.

2R45Cjn.jpg

if you are seeing ~200ms access time in the task manager directly after Watch Dogs goes sideways then that's a result of the drive being bottlenecked. 200ms access time is not normal for any SSD. As for what's causing it, as i said it could be because the SSD has no cache. Write performance is way more reliant on cache than read, so maybe something is writing a lot of data too it when Watch Dogs tanks? You need to look at everything else your PC is doing when this happens.
 
Yes, it can be played on 4K + Medium textures on my system without freezing. This made me think it was a VRAM issue before, but it's definitely the SSD.

In a way, I'm not that surprised, as the last Ubisoft AC game I played had problems with texture streaming on a hard disk drive.

WD Legions is a very odd game, I tried to load the page file onto a RAM disk, but the page file climbs to 10GB then crashes lol. Probably needs 11-12GB page file with the settings I'm using.
 
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So, has no one else had the problem with Watch Dogs: Legion? You need to set the game resolution to 4K, then enable High / Ultra Texture resolution in the game settings.

I suspect the issue doesn't occur on NVME drives.
 
g67575 said:
I left task manager running on my 2nd monitor and I noticed that when the game freezes, the active time on the SSD I installed the game on reaches 100% and doesn't return to 'normal' until the game resumes again (usually takes about 30 seconds). When the freezing issue happens, the game is heavily writing to the page file and swap file.

The active time (read access time) of my BX500 Crucial 2TB SSD is apparently approx. 220 microseconds, so not the best. Other performance stats of the drive seem fine though.

The latest consoles use NVME drives, which have much lower access times (and we know Ubisoft doesn't put much time and effort into PC ports).

As far as I can tell, the VRAM was not a factor in this freezing, except that higher texture settings result in more data being read by the SSD.
Click to expand...

When I was shopping around for a high capacity sata SSD a few months ago I specifically avoided DRAM'less drives like the BX500 as there's a fair few issues and general weirdness you can run into, I wouldn't be surprised if your predicament is down to that.
 
g67575 said:
So, has no one else had the problem with Watch Dogs: Legion? You need to set the game resolution to 4K, then enable High / Ultra Texture resolution in the game settings.

I suspect the issue doesn't occur on NVME drives.
Click to expand...

Your reason for believing that is access times but i've already shown you access times on sata SSDs are directly comparable. Without any other information (I have made suggestions already....) Then the lack of cache is the primary suspect. An NVMe drive may well fix your problems, but not because it's an NVMe drive...
 
The game loads all the game assets and textures onto the system's committed memory. Some of this committed memory will be the page file (virtual memory). I know this because if the page file is disabled, committed memory (now just 16GB on my system), is entirely allocated as the game loads into a level, then the game crashes.

In theory, another 8/16GB of system RAM would probably mean the game doesn't use the page file / disk to load textures at all, as all the committed memory can be physical RAM if the page file is disabled.

I don't have an SSD with DRAM cache (except a small OS drive), but feel free to test it. I haven't seen any evidence that suggests that there would be this kind of performance deficit with a DRAMless SSD (there seem to be a lot of assumptions about real world performance for some reason, even though most SSDs have an option to use system RAM as a cache for the SSD).

An SSD cache "caches the most frequently accessed data ("hot" data) onto lower latency Solid State Drives (SSDs) to dynamically accelerate system performance. SSD Cache is used exclusively for host reads". Link here:
https://mysupport.netapp.com/NOW/pu...UID-74019039-D7CD-4628-8BE5-334B47DD94BE.html

It's obvious that a NVME SSD (might as well get one with a DRAM cache too) would be the best bet though, to run the game without stuttering, why waste time on a sata drive? NVME drives have approx 5-10x faster read access times, and noticeably higher 4K read and write performance, compared to a Sata SSD with DRAM cache, example here:

https://www.elinfor.com/article/S/S/SSD (2).png
 
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