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Re: How to optimize my settings for best performances ?

Posted: Fri Jul 12, 2019 8:51 am
by NemeWheel
Jaga wrote: Thu Jul 11, 2019 11:45 pm Which mode to use is a bit trickier, it really depends on your goals, the delay time, etc. I have mine optimized for gaming with a defer time of 300s using the Intelligent write mode, but I have the longer delay coupled with a large L1 cache and a UPS on the machine. You'll probably want to use either Idle, or Idle-Flush since your delay time will be much shorter.
My main goal is to have the lowest possible load times in games as my use of PrimoCache is only based on this. In a way, my goal is to transform my HDDs into "SSD" and in the future, to buy a high capacity HDD rather than a high capacity SSD because financially it is more interesting ^^

That's why I created this topic in order to have the best possible parameters to obtain the best possible performances ;)

But otherwise, I have taken note of your recommendations for the parameters to be performed on the Defer write ;)

Also, I had another question about the Cache Hit Rate : I understood that the higher percentage was, the better was. However, what exactly does that correspond to?

Re: How to optimize my settings for best performances ?

Posted: Fri Jul 12, 2019 10:25 am
by Jaga
High hitrate means that an application or the OS requested information be read from the drive, but since it was already in the Cache Task it didn't need to query the drive for the data. Primocache simply intercepted the call and delivered the information from the cache instead, which bumps up the hitrate each time it happens. If the data wasn't in the cache when requested it has to be read directly from the drive instead, which bumps the hitrate down.

You can see the effect of this if you run a drive benchmark program with a data set size smaller than your cache size. Empty the cache task completely, then run the benchmark. At the end you should see abnormally high hitrate - all the files used for testing were created in the cache task and used there for the entire run. In your case you may see a lot of urgent writing going on, but that's expected.

Re: How to optimize my settings for best performances ?

Posted: Fri Jul 12, 2019 11:22 am
by ferrari
I would use Average mode for defer writes, writes data at a slower rate so as to not interfer with reads so much and if the write buffer does overflow it's a little faster to use your pc with average. Intelligent or idle flush waits before your comp is idle before flushing data so it can build up sometimes and overflow your write cache if it isn't very big.

Re: How to optimize my settings for best performances ?

Posted: Sat Jul 13, 2019 8:52 am
by NemeWheel
ferrari wrote: Fri Jul 12, 2019 11:22 am I would use Average mode for defer writes, writes data at a slower rate so as to not interfer with reads so much and if the write buffer does overflow it's a little faster to use your pc with average. Intelligent or idle flush waits before your comp is idle before flushing data so it can build up sometimes and overflow your write cache if it isn't very big.
Jaga wrote: Fri Jul 12, 2019 10:25 am High hitrate means that an application or the OS requested information be read from the drive, but since it was already in the Cache Task it didn't need to query the drive for the data. Primocache simply intercepted the call and delivered the information from the cache instead, which bumps up the hitrate each time it happens. If the data wasn't in the cache when requested it has to be read directly from the drive instead, which bumps the hitrate down.

You can see the effect of this if you run a drive benchmark program with a data set size smaller than your cache size. Empty the cache task completely, then run the benchmark. At the end you should see abnormally high hitrate - all the files used for testing were created in the cache task and used there for the entire run. In your case you may see a lot of urgent writing going on, but that's expected.
Hello ! Thanks for your answers ;)

I changed my settings following your recommendations, that's what I did:

- Activation of the Defer Write with a latency of 10 seconds with the average mode

- 90% of Read and 10% of Write in the advanced settings of the L1 Cache (I left 2 GB of RAM in OS Managed Memory, well or should I increase to 3 GB for example?)

- Modification of the Block Size from 64KB to 32KB (beyond, I think it will consume me too much RAM ...)

All my other settings remained as they were shown at the very beginning of this topic.

What do you think ??

Re: How to optimize my settings for best performances ?

Posted: Sat Jul 13, 2019 11:28 am
by ferrari
Those settings sound good for your configuration. As for the L1 cache size you want it as big as you can get without hitting the pagefile.sys, so try it for a couple of days with 2Gb and if you can see there's no pagefile.sys activity maybe raise it to 3-4Gb. I have 16Gb ram and use a 2Gb L1 cache, but I also have a Virtual machine running all the time that takes 3Gb of ram, if I didn't have that I'd choose a much bigger L1 cache of 4Gb maybe.

Re: How to optimize my settings for best performances ?

Posted: Wed Jul 17, 2019 9:28 am
by NemeWheel
ferrari wrote: Sat Jul 13, 2019 11:28 am Those settings sound good for your configuration. As for the L1 cache size you want it as big as you can get without hitting the pagefile.sys, so try it for a couple of days with 2Gb and if you can see there's no pagefile.sys activity maybe raise it to 3-4Gb. I have 16Gb ram and use a 2Gb L1 cache, but I also have a Virtual machine running all the time that takes 3Gb of ram, if I didn't have that I'd choose a much bigger L1 cache of 4Gb maybe.
Hello ! Thank you for your post and sorry to answer only now, I was very busy these last days ^^

I did some tests with my new settings and it works very well, nice perfs!

You tell me about pagefile.sys but how can I see that?

Also other question: currently I am using a 120GB SSD in SATA 3 as SSD cache in PrimoCache. But I also have a 256GB SSD in M.2 NVMe for Windows + software / apps + some games. Since it is an M.2 NVMe SSD and the read and write rates are much better than a SSD in SATA 3, if I use a part of this M.2 NVMe SSD in cache SSD (let's say 64GB), I would have much better performance no?

Re: How to optimize my settings for best performances ?

Posted: Wed Jul 17, 2019 8:02 pm
by Jaga
NemeWheel wrote: Wed Jul 17, 2019 9:28 amAlso other question: currently I am using a 120GB SSD in SATA 3 as SSD cache in PrimoCache. But I also have a 256GB SSD in M.2 NVMe for Windows + software / apps + some games. Since it is an M.2 NVMe SSD and the read and write rates are much better than a SSD in SATA 3, if I use a part of this M.2 NVMe SSD in cache SSD (let's say 64GB), I would have much better performance no?
Yes, but not if the volume you are caching (the C: drive on the NVMe) also has the L2 volume as another NVMe volume. It would effectively slow it down instead due to overhead. The L2 cache volume should always be a different physical drive than the drive that is being cached. If you are using another volume on the NVMe as a L2 to cache a different physical drive, then it will definitely be faster than the SSD. Your hitrates may drop if the L2 fills up (since it is only 50% the size of the SSD L2 volume), but you can determine that yourself through use.

Re: How to optimize my settings for best performances ?

Posted: Thu Jul 18, 2019 7:44 am
by ferrari
Yeah the NVME would most likely be slightly faster and I wouldn't worry about having a big L1 cache size too much, because of the high amount of data the games drive reads the L1 cache wouldn't be big enough to get a decent hitrate unless you dedicated maybe 8Gb to it which is too much I'd say. Keep a small L1 cache maybe 1Gb just big enough for background writes for your games drive.
For your OS drive an L1 cache of 1.5Gb is big enough to get a hitrate of 50% if you don't have any big games or programs on your OS drive.