PVE uses 80% of memory

[Businezz]

Hi everyone,

I have a server with 2 x 1TB storage - raid 1, 64GB of ram, AMD 5600G CPU. I created 1 VM where i use cPanel with 16 GB ram, and i can see that the PVE host jumped up to 80% (almost 50GB) RAM usage. What can cause this? I went through the forum posts and i see this can be just caching. If it is, when i deploy new VM let's say with 16GB ram, i guess i shouldn't have any issues?

ARC size (current):                                    96.9 %   30.1 GiB
        Target size (adaptive):                        97.3 %   30.2 GiB
        Min size (hard limit):                          6.2 %    1.9 GiB
        Max size (high water):                           16:1   31.1 GiB
        Anonymous data size:                          < 0.1 %  468.0 KiB
        Anonymous metadata size:                        0.0 %    0 Bytes
        MFU data target:                               82.7 %   24.3 GiB
        MFU data size:                                 86.9 %   25.6 GiB
        MFU ghost data size:                                     1.0 GiB
        MFU metadata target:                            3.2 %  970.6 MiB
        MFU metadata size:                              1.4 %  411.2 MiB
        MFU ghost metadata size:                                 0 Bytes
        MRU data target:                               10.9 %    3.2 GiB
        MRU data size:                                 11.5 %    3.4 GiB
        MRU ghost data size:                                    12.6 GiB
        MRU metadata target:                            3.2 %  970.6 MiB
        MRU metadata size:                              0.3 %   81.5 MiB
        MRU ghost metadata size:                                 0 Bytes
        Uncached data size:                             0.0 %    0 Bytes
        Uncached metadata size:                         0.0 %    0 Bytes
        Bonus size:                                   < 0.1 %    1.6 MiB
        Dnode cache target:                            10.0 %    3.1 GiB
        Dnode cache size:                               0.3 %    8.3 MiB
        Dbuf size:                                      0.1 %   22.3 MiB
        Header size:                                    2.2 %  675.7 MiB
        L2 header size:                                 0.0 %    0 Bytes
        ABD chunk waste size:                         < 0.1 %  601.5 KiB

ARC hash breakdown:
        Elements max:                                               3.3M
        Elements current:                              90.3 %       2.9M
        Collisions:                                                10.5M
        Chain max:                                                     7
        Chains:                                                   410.6k

ARC misc:
        Deleted:                                                   19.2M
        Mutex misses:                                               6.8k
        Eviction skips:                                             3.4k
        Eviction skips due to L2 writes:                               0
        L2 cached evictions:                                     0 Bytes
        L2 eligible evictions:                                 429.5 GiB
        L2 eligible MFU evictions:                     47.6 %  204.6 GiB
        L2 eligible MRU evictions:                     52.4 %  224.8 GiB
        L2 ineligible evictions:                                 4.2 GiB

root@pve:~# free -h
               total        used        free      shared  buff/cache   available
Mem:            62Gi        48Gi        14Gi        49Mi       166Mi        14Gi
Swap:             0B          0B          0B

 

[leesteken]

I have a server with 2 x 1TB storage - raid 1, 64GB of ram, AMD 5600G CPU. I created 1 VM where i use cPanel with 16 GB ram, and i can see that the PVE host jumped up to 80% (almost 50GB) RAM usage. What can cause this? I went through the forum posts and i see this can be just caching. If it is, when i deploy new VM let's say with 16GB ram, i guess i shouldn't have any issues?

Max size (high water): 16:1 31.1 GiB

So many threads about this, that's is actually added to the manual: https://pve.proxmox.com/pve-docs/pve-admin-guide.html#sysadmin_zfs_limit_memory_usage

EDIT: Indeed this is normal and should not cause problems. But feel free to adjust the ARC max.

 

[Businezz]

So many threads about this, that's is actually added to the manual: https://pve.proxmox.com/pve-docs/pve-admin-guide.html#sysadmin_zfs_limit_memory_usage

EDIT: Indeed this is normal and should not cause problems. But feel free to adjust the ARC max.

So, basically on a 1TB storage i should drop it to 3gb… based on the manual. Also i was reading somewhere, having larger amount is it better?

 

[Dunuin]

The more is read from RAM the faster the Pool will be. So yes.