Questions about L2 and Settings

[Tobiwan]

Hi there,

first of all, sorry about the question and maybe my bad English, it's not my native language, I'm testing PrimoCache 3.0.2 now since good 30 days and plan to buy it the next days, but I have a few questions that I don't really understand with the FAQ etc.

Currently I'm only using the it with Level 1 Cache and the following settings
- 8 GB shared memory + Release L1 Cache on Hydrid-Sleep or Hibernation
- 32KB Block Size
- Defer-Write with Intelligent Mode at a 10 sec latency

The system runs good so far and there is no problem, the Cache Hit Rate is very low as example my OS SSD after one day has 5,81% Hit Rate...

More RAM size or going from 32kb to 16kb doesn't really any change for me, maybe is 8GB even to much and I should go to a lower block size?

My system specs are i7 7700K, 1080TI and 32 GB RAM, 2x Samsung 850 Evo, 1 Samsung 860 Evo with the OS and 2x 3TB Seagate HDDs + 1 Toshiba 4TB

With my OS SSD Samsung 860 Evo and my setting I get at Samsung Magician Benchmark:
Read: 9422 / Write: 8791 and Read: 101806 / Write 92773
The two 850er goes to:
Read: 8262 / Write: 7899 and Read: 102050 /Write 90332
Read: 8358 /Write: 8053 and Read: 107177 /Write 95458

My questions are now, I know with only L1 Cache and Defer-Write there can be maybe a data lost, I could install a second Samsung 860 Evo and use one of it for a Level 2 Cache, but isn't that really a benefit at performance or misunderstand it something? The DDR4 Ram boost everything because it runs faster than the SSD or HDD, if I use now a SSD to cache something and write data to the SSD does it not slow down the speed back to the SSD speed?

Or is it maybe better to set a small part on every SSD/HDD as L2 like Over Provisioning?

So in case I would buy a new Samsung 860 Evo SSD only for L2 caching can I only use the SSD than for the cache or is the cache only a small part of the SSD? Or should I buy a small 256er Samsung Pro with more speed for the cache? I really doesn't understand that with the L2 caching.

Did I need a Windows pagefile anymore with PrimoCache? I read something about it get's cached too, but is it really useful anymore with 32GB RAM

A yeah one last question I got, that's about external HDDs, can I cache that with PrimoCache without problems, I have a few Western Digital hard drives with AES encryption, can I make a cache for the HDDs that remember the HDDs on connection and work with them?

Any news about a new version? The version 3.0.2 is now almost 1 year old and Windows got a lot of updates since that.

Thanks guys

Tobi

[Support]

Please upload a screenshot of your current PrimoCache main dialog with cache configuration and statistics showed. Thanks.

[Tobiwan]

Bad timing right now, because I made delete the current settings.

I use MiniTool Partition Wizard Free 10.3 and create a from my main Samsung 960 Evo a 6GB partition and try to use it as L2 cache... Not sure about it, if it works or not at this way. Currently I have a free SATA port and can buy a new SSD for that job.

But before I can test ever thing I need to fix a HDD drive that I "broke", its showing as RAW but the tools and Windows says its NTFS...

[Support]

you may try chkdsk to check the broken file system.

[Tobiwan]

The problem is, one of my HDDs (Toshiba HDWE140 4TB) is displayed as RAW at the Windows workplace and DIskmanager don't let me have any access on it. But on the tools like MiniTool Partition Wizard, testdisk 7.1 WIP or EaseUS Partition Master Free the HDDs is NTFS and not RAW. All data on the disk is there but I have no access to it. chkdsk doesn't work completely on that HDD because I get a weird error message. I can copy the data, but have no diskspace for that many data right now.

[Tobiwan]

Ok I'm back and everything runs so far again and I bought a license for PrimoCache. Can some one give me some answers about my questions at the first post and tips/hints about my settings. Is there anything wrong or can I made something better?

I made now a L2 cache with 6 GB at my Samsung 860 EVO. First I wasn't sure what L2 exactly did, but now I know it, it's the same as you use a Intel Optane, it boosts the "old" HDDs but does nothing with SSDs.

Here you can see my current settings:
https://picload.org/view/dcrairci/primocache1.jpg.html

[Support]

You may increase cache block size to reduce memory overhead. Current setting consumes about 4.7GB which is too much.
L2 cache size seems too little compared to target HDD capacity.

[Tobiwan]

Next week my new Samsung 860 Evo with 1TB should arrive me, there was a very cheap offer for it, I move the L2 cache to the new 1TB SSD and make a new size for it. The are 4 HDDs with total 16TB dataspace, all movies, big files, copys etc. plus external HDDs, but I don't sure about caching them.

So at the moment the hit rate is most of the time at 100%, so yeah, the sizes seems to low. If I see the 16TB HDD how big should I set the L2 cache size? 50GB maybe or higher?

Does the L2 cache help against losing files at problems with Defer? If I see it right, L2 cache is used by my SSDs and HDDs, but I need it only on my HDDs?

[Support]

It depends on the amount of hot data which you frequently access to decide L2 cache size for a better performance.

Does the L2 cache help against losing files at problems with Defer?

No. So far same risk.

If I see it right, L2 cache is used by my SSDs and HDDs, but I need it only on my HDDs?

L2 concept is using a faster drive to speed up a slow drive. So it is possible you use a fast SSD to speed up a slow SSD, though usually we use SSD to speed up HDDs. You can disable L2 for certain volumes in the "Volume Specifications" (cache configuration).