Trying to understand all this. (NEWB)

[brighttail]

Hey all,

First off I should give a few specs of my system.
Asus R5E10 MB
Corsair Dom Platinum 32GB RAM
Samsung 950 pro. 256gb
2x Samsung sm961 256gb
Samsung 850 pro 512gb
WD black 4TB

Up to now I was using my 950pro as my OS drive and made a raid 0 drive with my two sm961s and used this for gaming.

I do some video editing and I use the 850 pro to store web downloads and of course the WD 4tb as a main storage of larger (completed files) I also have a NAS for a 2nd backup and an External USB HDD as my 3rd redundant backup.

In the past I have used the Asus Ramcache, but I find that this is limited to a single drive to cache. Basically I'm looking for speed. I have a RamDisk setup to house browser cache/Windows Temp files and set that to 4GB. I figure I have about 12-16gb left that I'm just not using on a consistent basis.

So. From what I read I can make a L1 cache that may help speed up my OS drive a bit. Just testing it in Crystal Diskmark and a few others, it does seem to do the trick.

I have found that using Raid 0 on the m.2s really doesn't give me real time performance gains unless I'm moving large files, so I was considering using only ONE for gaming, play and my video applications and thought I could use the other as an L2 cache. Then I read that since I already have an SSD m.2 drive for my Applications, I am not going to see much performance using an L2 cache. The only reason I would want to use it is to speed up some apps while having it have the safety net to write to a disk in case of power outage.

So with all that being said, is there any benefit from using an m.2 as an L2 cache? I'm sure it will help with the WD HDD and maybe a little with the slower Samsung 850 Pro SSD.

Any suggestions here?

Thanks.

*note* For fun I put one of the SM961 as an L2 cache using max. I have read/write on and deferred writes 10sec. Using it for 30 minutes moving around an have a 95% cache, which I'm sure will go down as I use it more. I have a feeling i'm really not doing anything special and it only seems like things are moving faster, but the crystaldisk mark is well over 10k for sequential read/writes and 4k read/writes right at 1k, same with 4k at q 32. So on the surface.. wow. I must be missing something.

[brighttail]

Okay did some more research and found SSD > L2 > HDD.

So no real reason for me to have an L2 except for my WD HDD.

L1 for my C: drive... would it also be good for my D: application drive? Also would there be any benefit to creating an 8Gb L1 Cache for these two drives?

[brighttail]

Reading more and more and more...

I guess I really don't fully understand all this. 8GB is way too much for L1 as this isn't a RAMDisk. Ah well. No reason for me to purchase this if I can't figure out what it can do for me. Fun to see lots of numbers in the 10k range and bootup/shutdown a lot faster but with my computer I'm not sure it really does anything for me.

Thanks tho.

[Babel17]

If you enable read caching, and pre-fetching, then the game you played yesterday can have a lot of it loaded into memory today. Even without pre-fetching you can get faster loading of game levels as they can be cached. And as long as you don't reboot Windows they can stay in the cache. With pre-fetching enabled, Primocache will reload information from the game after the system reboots. Unless it got "pushed out" by data that later got cached. This is why some people use gigabytes of memory for caching.

[BonzaiDuck]

He's right, brighttail.

It's your choice. Apparently demand for Primo has increased, because they used to offer a 90-day trial, and last I checked, it was changed to a 60-day trial-period.

Before I purchased my 960 Pro 1TB more than a week ago, I had been experimenting with a 250GB EVO as SSD-cache. If you read some other recent thread(s) with my stamp on them, you'll see I had a question about whether benchmarks will pick up an indication about the L2 cache. They won't, because Primo uses a "stealth" strategy to cache when the system is idle. SUPPORT told me they will release version 3.0 which actually does "write" caching to the SSD, no longer escaping from "benchmark detection."

I'm putting all sorts of programs on a 2.5" 2TB 5,400 RPM Barracuda drive. With the RAM-caching, it is surely great, but you could really feel the difference with an L2 cache. People are skeptical, suggesting I should just get an SATA SSD and replace the spinner with it. But the spinner has capacity, and the caching -- tailored to personal usage patterns, makes the limitations of the HDD seem almost non-existent.

With 32GB of RAM, you will also get great results, but hibernation and pagefile will mean more writes to your boot-SSD or larger writes. Of course, you can put the page file on the HDD, and it will be cached with files accessed from that HDD. You could set the hiberfil.sys to 50% of RAM -- a minimum limit. No problem with that.

With the 960 EVO experiment, I cached my SATA SSD boot-system disk to a 40GB caching-volume allocation, and the HDD allocated another 60GB. That was less than half the size of the EVO. Things were getting so fast, it seemed almost scary. Thought I'd get a heart-attack racing in GRID2 . . . .

[InquiringMind]

Welcome to the forums Brighttail,

I have found that using Raid 0 on the m.2s really doesn't give me real time performance gains unless I'm moving large files, so I was considering using only ONE for gaming, play and my video applications and thought I could use the other as an L2 cache. Then I read that since I already have an SSD m.2 drive for my Applications, I am not going to see much performance using an L2 cache. The only reason I would want to use it is to speed up some apps while having it have the safety net to write to a disk in case of power outage.

As you've noted, L2 caching serves no purpose for data held in SSD - it's purpose is to speed up access to HDDs. If your HDDs are used solely for storing downloads and media files (where speed is of little importance as long as it is fast enough to support playback), then L2 setup can be ignored.

As far as RAID-0 goes, you do gain the benefit of having 2 separate disks treated as one larger one. 256GB may be enough for you currently, but it is quite possible to exceed this with modern games using 20-50GB space.

...8GB is way too much for L1 as this isn't a RAMDisk. Ah well. No reason for me to purchase this if I can't figure out what it can do for me. Fun to see lots of numbers in the 10k range and bootup/shutdown a lot faster but with my computer I'm not sure it really does anything for me...

If you have the memory to spare, then 8GB+ is perfectly reasonable for a L1 cache (you mention having 12-16GB free, so I would suggest 10-12GB to give yourself a safety margin). You may wish to experiment with block sizes (I found 64KB the best for my situation) but the best way to judge PrimoCache is to use your system as normal for a while. Then disable PrimoCache and see if things seem slower - if they do, then PrimoCache is providing you with a noticeable benefit.

[BonzaiDuck]

I guess the only caveat I can offer for that speaks to the new NVMe M.2 drives. While an SATA SSD is "fast enough" for most anyone, you can cache an SATA SSD to an NVMe and begin to see a real boost in performance, just as you might see caching an HDD to an SATA SSD (or NVMe, for that matter -- also). But if I were building a computer system and setting it up for someone else -- assume I might have "customers" -- I wouldn't introduce any of these complications we discuss here.

The beauty of PrimoCache is its versatility. But you customize your system even more than without it, and it requires attention.

[brighttail]

Thank ye for the suggestions I did use it and it did well until the new Windows update as of April 11.

[BonzaiDuck]

Thank ye for the suggestions I did use it and it did well until the new Windows update as of April 11.

We'll all get ahead of this. Just a matter of time.