Memory used almost maxed out

TrueNAS General
1

hi my truenas core zfs cache is at 25.6 gb normally its .2 gb it does not go back to normal until i reboot
right now i am copying files from system to windows 11 usb drive
(still working on usb connections)
i have no containers or jails at present
is this normal when copying files

‘my system
CW-8505-NAS V1.0
System Information Overview
Preformatted text`Platform: Generic
Version: TrueNAS-13.3-U1.2
CW-8505-NAS V1.0
Intel(R) Pentium(R) Gold 8505
Memory 31.7GiB 2x16 ddr5 3200
Free: 27.9 GiB
ZFS Cache: .2gb
Services : 3.6gb
Media Type: Ethernet
Media Subtype: 1000baseT
Name Serial Disk Size Pool Model Rotation Rate (RPM)
ada0 WD-WCC4E73N7CPZ 3.64 TiB containerjail WDC WD40EFRX-68WT0N0 5400
ada1 ZADA6WG9 5.46 TiB storage2 ST6000VN0033-2EE110 7200
ada2 ZADAK6X1 5.46 TiB storage2 ST6000VN0033-2EE110 7200
ada3 ZDH16KG9 3.64 TiB containerjail ST4000VN008-2DR166 5980
ada4 UB202411110464 119.24 GiB boot-pool ORICO
ada5 UB202411110432 119.24 GiB boot-pool ORICO
ada6 WWZ0YGN8 7.28 TiB N/A ST8000NM017B-2TJ103 7200 ?
ada7 WWZ15T38 7.28 TiB mediapool1 ST8000NM017B-2TJ103 7200
ada8 3684K0T9FUUB 5.46 TiB md6000-6tb MB6000GEXXV 7200
ada9 3686K0VEFUUB 5.46 TiB md6000-6tb MB6000GEXXV 7200’

2

Is the high ram use causing you any issues? Or are you just worried about the high ram use?

If it is just the latter than I probably wouldn’t worry about it. It is doing it’s job of caching files that you might want to read again in the ram so that it doesn’t have to go back to your pool to fetch the data.

It lowers after reboot because the ram erases when power is removed. Basically it is like starting with a clean slate, or in this case with an empty cache.

If you want, I believe that you can limit the size of the cache.

Tldr: if you are just worried about the high usage, it is probably not a big deal.

3

thanks i was worried that i would not have any ram left to add vms or other apps

you have made my day a little better

4

zfs is so smart that it shrinks itself down if memory is needed by other system processes, like vms or docker containers

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