Couple Questions and feature request? Topic is solved

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SnowReborn
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Couple Questions and feature request?

Post by SnowReborn »

apology in advance that I am posting this in tech support since I needed both help and making suggestions at the same time. :?

1. I often ran into the need of pausing particular cache tasks which I created and only resume them under certain situation. However, every time the PC restarts, primo automatically resumes those tasks; and I have to manually pause them again. I am aware of the command line tools but that is only a workaround and it's not super convenient to do with large amount of tasks. It would been nice if there is an option or checkbox to have previously paused tasks continues to be paused after PC restarts; or if there are other workaround, please let me know.

2. I wonder if there is a way to truly "lock cache content" of either L1 or L2 cache. I am aware the "lock cache content" is available as L1 as an option to lock cache content and restore it upon windows boots; but I am looking for a feature that locks the cache content even during current windows session; so the primocache will not cache in new content(as if the cache task is paused), but only update existing cache blocks and still provide read benefits(as cache is not paused). (I often need the benefit of read cache to speed up the system, but sometimes I have to pause the cache to avoid primocache caching in large unwanted read / write activities; but during this time is often when I need primocache's cache the most during heavy disk activity, and those activity I do not want them to be cached.). Is it possible to keep the cache on and not caching in new content and only update the existing content?

3. I have ran into couple L2 cache issues; specifically creating L2 Cache storage. sometimes after a PC crash(bsod or similar), I would manually restore my OS with backup software in PE enviroment, and to ensure no "offline modification" or data corruption, I would remove the primocache tasks from PE via registry. (both vol and repo keys); I boot into the restored OS, opens primocache and it shows no cache tasks(as expected since i've deleted them via registry). However, when I try to create L2 cache. The previous L2 cache which has been assigned to a cache tasks is unavailable and as if it was still assigned to a "ghost tasks" that I deleted. I have to manually format the old L2 storage (which always fails to format if I assign a drivel letter to it), if I don't assign a drive letter and simply deletes it, and it works(but I want to assign a drive letter to better identify it). So in summery, It would be nice if the L2 storage automatically becomes available if the original task was deleted; and the formatting L2 storage back into a partition needs to be fixed as current it will attempt to format, and fails, and windows will ask you to format it again.

4. I have question regarding "offline modification". I am very careful when it comes to dual booting, and sometimes I do have the need to do so. Everytime I dual boot I have to delete primocache's tasks and rebuild the L2, which is tedious and bad for SSD's write cycle. One tedious way to prevent offline modification in dual boot enviroment is just to physically remove the disks which is associated with another OS. but that is very annoy and hard to do because of m.2s and GPUs(basically tearing entire pc apart). Although I could disable SATA controller in the bios, but there is no way to disable Nvme drives since it's PCIE based, not even in bios as far as I know :eh: ; and on top of that, sometimes I do need to access the disks which was associated with primocached OS(only need read access like file copy etc). I wonder if there is any way we can lock the disks from being accessed in another OS? Better yet if there is a way to mark the disk "read-only" it should also do the trick while providing the access and data to dual boot and prevent "offline-modification" to primocache if my understanding is correct(i am aware in windows diskpart can set read-only markers, but not sure how reliable it is). I also wonder if it is considered "safe" to just ONLY booting up into an PE enviroment in regard of primocache's L2 offline modification. Does simply booting into the PE will have risk of modifying or corrupting the L2 cache?(obviously the OS sees the drive and have access to it, which is worrysome for data integrity. If only booting into PE without user's action making any changes to the disks is safe, then would Diskpart "attributes disk read only set" command sufficient to prevent any offline modification if I need to "read" or "access" the data on the cached disk in an offline enviroment?

5. I've created a dedicated partition just for my page file(so I can exclusively use primo cache on the page file without affecting other files). Even though I have 128GB of memory, sometimes page file is still being used under some circumstances(either because I actually ran out of 128GB ram, or my Machine learning AI script ran out VRAM(video memory) and is dumping VRAM into page file even my RAM is still available) regardless. I am aware in the old versions it is not recommended to cache page file with primocache since it can cause dead lock; but with new version 4.2.0, is it safe to use deferred write on page file with L1 cache? If it is safe, do I have any risk if my actual RAM usage is very high? say on the border of maxing out 127gb/128gb?

Many Thanks!
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Re: Couple Questions and feature request?

Post by Support »

1. Currently no such option. We consider to support it in future. A workaround might be removing volumes from the cache task and adding back when needed. These operations can also be done via Command-Line.

2. This function will be available in the next version.

3. You can delete the L2 partition which was assigned to a cache task. No need to re-format the L2 drive. Please see
https://www.romexsoftware.com/en-us/pri ... orage.html

4. If the target drive file system is not ReFS, it is safe when you just boot into another system without actions on target drives and L2 drive. Another way to ensure safe is to enable "Volatile Cache Contents" (L2 Advanced Options) before you are going to boot into another computer. This option will reset L2 cache when you boot back. Of course, this way is still not very convenient.

5. Yes, it's safe. PrimoCache pre-allocates all RAM cache needed for the cache task, it will not take much more RAM during the cache running.
SnowReborn
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Re: Couple Questions and feature request?

Post by SnowReborn »

Support wrote: Mon Nov 28, 2022 10:29 am 1. Currently no such option. We consider to support it in future. A workaround might be removing volumes from the cache task and adding back when needed. These operations can also be done via Command-Line.

2. This function will be available in the next version.

3. You can delete the L2 partition which was assigned to a cache task. No need to re-format the L2 drive. Please see
https://www.romexsoftware.com/en-us/pri ... orage.html

4. If the target drive file system is not ReFS, it is safe when you just boot into another system without actions on target drives and L2 drive. Another way to ensure safe is to enable "Volatile Cache Contents" (L2 Advanced Options) before you are going to boot into another computer. This option will reset L2 cache when you boot back. Of course, this way is still not very convenient.

5. Yes, it's safe. PrimoCache pre-allocates all RAM cache needed for the cache task, it will not take much more RAM during the cache running.
Hello! Thanks for the reply and support. I believe #1 really shouldn't be hard to implement as only needing to add some options for certain tasks to remember it's "pause / resume state", and enforce it next reboot, and save such option in registry key or config file, simply deleting the tasks is currently not what I wanted, but looking forward for the future feature implementation.

You answered most of my question, except issue #3. I still have issue with L2 partition. I have read the FQA on the link provided, and it didn't provide any extra info that I didn't already know. You mentioned the option to delete the L2 partition without reformatting or (converting the entire L2 back to normal drive). Yes, that would be great. But the "delete partition" button on the right hand side at the bottom is always greyed out; even after selecting the L2 Storage list, and L2 partition at the bottom box. see pic attached.
primo issue 4.png
primo issue 4.png (89.69 KiB) Viewed 276 times
as Mentioned above, I've never got that button to work, it's always greyed out. So I always just deletes the L2 storage list, and click format. However, there's also another issue with the L2 management formatting as well, often times if it was able to successfully format the L2 storage, the L2 storage label will be default, and in windows it will ask you to reformat to use it again; Furthermore, on most cases, the L2 management format would just fail, so I have to use disk management to format, which is very inconvenient because I have many drives and partitions, inside disk management it's hard to identify which is my cache partition and which is not; so I much prefer to use the primocache built in L2 Management tools, only if it works... See the picture below:
primo issue2.png
primo issue2.png (80.62 KiB) Viewed 276 times
This is the issue where after successful format, windows still ask you to format to access it, and the label of the partition is named as default "local disk", instead of what I actually named in the L2 format management.
primo issue.png
primo issue.png (139.08 KiB) Viewed 276 times
This is the issue where the L2 management just fails to format at all.
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Re: Couple Questions and feature request?

Post by Support »

The "Delete Partition" button should work. Can you try the deletion with CLI when you the partition is not used by any cache task? Below are steps and commands.
1) rxpcc ls -v
Find the L2 storage volume index in the command results.
2) rxpcc storage delpart -v # (replace it with the index you found in the last command) -p 0
This command is to delete the partition 0 in the L2 storage volume.
Type "rxpcc ? storage" see the help on the "storage" command.

For how to enter the CLI, please see https://www.romexsoftware.com/en-us/pri ... rface.html

Thanks.
SnowReborn
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Re: Couple Questions and feature request?

Post by SnowReborn »

Support wrote: Mon Dec 05, 2022 8:58 am The "Delete Partition" button should work. Can you try the deletion with CLI when you the partition is not used by any cache task? Below are steps and commands.
1) rxpcc ls -v
Find the L2 storage volume index in the command results.
2) rxpcc storage delpart -v # (replace it with the index you found in the last command) -p 0
This command is to delete the partition 0 in the L2 storage volume.
Type "rxpcc ? storage" see the help on the "storage" command.

For how to enter the CLI, please see https://www.romexsoftware.com/en-us/pri ... rface.html

Thanks.
Hello, Thanks for the reply. The above CL command worked. It successfully deleted the partition(linked to a ghost empty cache tasks) (and made it available to assign again) following the instruction provided WITHOUT converting it back to normal partition. This is exactly what I wanted. However, there's a couple things worth mentioning. The above command, rxpcc list -v listed all the volumes, however it also listed L2 partitions as "L2_storage" regardless the name I put when I created them. The rxpcc ls -l however, correctly lists the L2 storage names; I am not sure if this was intended feature or a bug, but I think as long as ls -l exist, it shouldn't be too much of a problem(it's nice to know which partition is L2 in ls -v, but it would be nice if it also shows the name I gave it).

Another thing, Can you tell me under what condition does the "delete partition" button work? It always stays greyed out during my testing, it would be really nice if it worked. Thanks!
SnowReborn
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Re: Couple Questions and feature request?

Post by SnowReborn »

Support wrote: Mon Dec 05, 2022 8:58 am The "Delete Partition" button should work. Can you try the deletion with CLI when you the partition is not used by any cache task? Below are steps and commands.
1) rxpcc ls -v
Find the L2 storage volume index in the command results.
2) rxpcc storage delpart -v # (replace it with the index you found in the last command) -p 0
This command is to delete the partition 0 in the L2 storage volume.
Type "rxpcc ? storage" see the help on the "storage" command.

For how to enter the CLI, please see https://www.romexsoftware.com/en-us/pri ... rface.html

Thanks.
Sorry, I have an update. Upon further testing, I would take my words back. The "Delete partition" button does seem to work, if the L2 partition cache was pointed to a ghost task; Then the button will not be greyed out, and when the cache is being used by a task the button is greyed out. Seems like expected behavior, but I did not notice this and always assumed it's greyed out, so never bothered to use it. This solves most of my issues and concerns. However, I failed to mention another issue #6 that I've encountered.

I have encountered a rare and strange issue back then; and I was NOT able to reproduce the issue. So I had a disk let's call it drive #1, the E: partition in drive #1 being cached by primocache both L1 and L2 and I have a F: partition that is not being cached; during normal windows session, I decided to shrink the E partition on drive #1 with windows management(probably without pausing or deleting the task), I shrinked 200GB out of the 14TB of E: partition. marking the new 200GB partition as G: partition. Then, I changed windows page file location into G:, I may or may not have assigned a primocache L1 task for G:, so now I have E: 13.8TB, G: 0.2TB, and F: 2TB. and restarted my PC. Upon POSTing and loading windows(spinning circle), my system would instantly BSOD(blue screen of death), and the error I believe was "rxfcv.sys"(not entirely sure); and it will always stuck on BSOD on boot. I was able to resolve the issue by going into a PE enviroment, load the hive of my original OS, and delete all the primocache tasks via registry. Any input as of what may have caused it, why it happened, and how can we prevent it happening again would be appreciated.

lastly, I would like ask a very general question. If the OS system partition is being cached by L1 cache, and "Defer write" option is ENABLED with Indefinite period. Since the primocache driver loads during windows bootup. Does that mean any ungraceful shutdown during the windows boot up before the login screen including the spinning circle, chkdsk countdown, Operating system boot menu selection(after spinning circle) are all prone to data loss and corruption? Thanks!
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Re: Couple Questions and feature request?

Post by Support »

SnowReborn wrote: Tue Dec 06, 2022 12:12 am I have encountered a rare and strange issue back then; and I was NOT able to reproduce the issue.
I'm afraid that this issue might be related to disk partition size change. As I remember, PrimoCache blocks the partition size change if the partition is being cached. Is it possible to find a minidump for the BSOD as described at the link below? Thanks.
https://kb.romexsoftware.com/en-us/3-ge ... leshooting
SnowReborn wrote: Tue Dec 06, 2022 12:12 am lastly, I would like ask a very general question. If the OS system partition is being cached by L1 cache, and "Defer write" option is ENABLED with Indefinite period. Since the primocache driver loads during windows bootup. Does that mean any ungraceful shutdown during the windows boot up before the login screen including the spinning circle, chkdsk countdown, Operating system boot menu selection(after spinning circle) are all prone to data loss and corruption?
Yes. It is not recommended to use the INFINITE latency. A small latency can reduce the risk of data loss. For more information about Defer-Write, please see https://www.romexsoftware.com/en-us/pri ... write.html
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Re: Couple Questions and feature request?

Post by SnowReborn »

Support wrote: Wed Dec 07, 2022 6:27 am
SnowReborn wrote: Tue Dec 06, 2022 12:12 am I have encountered a rare and strange issue back then; and I was NOT able to reproduce the issue.
I'm afraid that this issue might be related to disk partition size change. As I remember, PrimoCache blocks the partition size change if the partition is being cached. Is it possible to find a minidump for the BSOD as described at the link below? Thanks.
https://kb.romexsoftware.com/en-us/3-ge ... leshooting
SnowReborn wrote: Tue Dec 06, 2022 12:12 am lastly, I would like ask a very general question. If the OS system partition is being cached by L1 cache, and "Defer write" option is ENABLED with Indefinite period. Since the primocache driver loads during windows bootup. Does that mean any ungraceful shutdown during the windows boot up before the login screen including the spinning circle, chkdsk countdown, Operating system boot menu selection(after spinning circle) are all prone to data loss and corruption?
Yes. It is not recommended to use the INFINITE latency. A small latency can reduce the risk of data loss. For more information about Defer-Write, please see https://www.romexsoftware.com/en-us/pri ... write.html
Thanks for the response! Interestingly during the resizing the partition I do not believe I see any message from primocache; and as expected is probably due to partition size change. Unfortunately I have already restored my drive with image file and did not keep the minidump. If eventually I have free time I would try to reproduce the issue and update with another thread; and thanks for letting me know when the defer write mechanism kicks in, that's all I need to know, even though it's not recommended, I decided for my use case I would like to reduce my SSD write cycle with indefinite defer write. Of course I have counter measure such as having UPS for sudden power loss, and weekly imaging backup of my drive for sudden system crash etc. So I am prepared and decided the defer write pro out weights the cons. I will mark my question as solved. Thanks again with your time and help, keep up the good work, this is great community and great software! :clap:
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