No Writes to L2 Cache Topic is solved

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xenoskepsi
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No Writes to L2 Cache

Post by xenoskepsi »

Hey all,

I have a 100TB disk pool that I'm trying to accelerate with a 1TB NVME used as an L2 cache. I have it set up with Individual Read/Write Cache Space (50/50 split) and my Gather Interval is INSTANT (just to be sure). I'm using a 512 block size and Defer-Write is set to 10 sec.

It's been set up for over a week and I have yet to see and read/write performance improvement. The L2 cache looks empty.

Am I missing something obvious? I've followed the tutorials and it looks like it should be working.

Thanks for the help.
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Re: No Writes to L2 Cache

Post by Support »

Could you please upload your cache configuration and stats for our reference by following the guidance in the link below?
https://kb.romexsoftware.com/en-us/2-pr ... leshooting
xenoskepsi
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Re: No Writes to L2 Cache

Post by xenoskepsi »

Configuration and Statistics:
PrimoCacheConfigStats.png
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Re: No Writes to L2 Cache

Post by Support »

I see "Total Write (Req)" is 0 which means there was no any write IO requests to the disk pool. Does the disk serve for writing? Can you upload the screenshot of the full main dialog?
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Re: No Writes to L2 Cache

Post by xenoskepsi »

Support wrote: Fri Feb 24, 2023 7:31 am I see "Total Write (Req)" is 0 which means there was no any write IO requests to the disk pool. Does the disk serve for writing? Can you upload the screenshot of the full main dialog?
Is this what you mean?
PrimoCacheDialog.png
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xenoskepsi
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Re: No Writes to L2 Cache

Post by xenoskepsi »

Support wrote: Fri Feb 24, 2023 7:31 am I see "Total Write (Req)" is 0 which means there was no any write IO requests to the disk pool. Does the disk serve for writing? Can you upload the screenshot of the full main dialog?
I have written over 100GB to the disk in the last week.
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Re: No Writes to L2 Cache

Post by minhgi »

do you have any disk fragment tool or other utilities that installed IO driver and interfering with Primocache own driver. Do you have "free cache on written" enabled?
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Re: No Writes to L2 Cache

Post by xenoskepsi »

minhgi wrote: Sat Feb 25, 2023 12:53 pm do you have any disk fragment tool or other utilities that installed IO driver and interfering with Primocache own driver. Do you have "free cache on written" enabled?
Where is the "Free Cache on Written" setting?

Do, as far as I know nothing would interfere... How would I know for sure?
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Re: No Writes to L2 Cache

Post by xenoskepsi »

minhgi wrote: Sat Feb 25, 2023 12:53 pm do you have any disk fragment tool or other utilities that installed IO driver and interfering with Primocache own driver. Do you have "free cache on written" enabled?
I found it. No, it is not enabled.
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Re: No Writes to L2 Cache

Post by Support »

"Total Write (Req)" is 0, so PrimoCache didn't see any write IOs. It seems that all writes were bypassed and directly to the drive. Is the drive used for VMs? Or any other software installed might intercepts writes?
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