Limit writing and reading when creating LXC Conteiner.

[Alex Porto dos Santos]

When I create a new container, the disk IO rate goes up a lot. I even consider it normal due to the extraction work being writing to the disk. However, this affects other containers that are on the same disk, degrading the performance.
I would like to know if there is a way to limit the disk IO so that it affects less the other containers.

I have a lot of containers on the same disk, but I only feel this performance degradation when creating new containers.
All disks are ssds.

Other solutions are also welcome.

CPU(s) 24 x Intel(R) Xeon(R) CPU X5650 @ 2.67GHz (2 Sockets)

Kernel Version Linux 5.3.18-3-pve #1 SMP PVE 5.3.18-3 (Tue, 17 Mar 2020 16:33:19 +0100)

PVE Manager Version pve-manager/6.1-11/f2f18736

 

[oguz]

hi,

in /etc/pve/datacenter.cfg or /etc/pve/storage.cfg you can set bandwidth/io limits.

see man datacenter.cfg for more information

 

[Alex Porto dos Santos]

Hello
Thank you very much for your reply.

I found the setting in the manual.
bwlimit: [clone = <LIMIT>] [, default = <LIMIT>] [, migration = <LIMIT>] [, move = <LIMIT>] [, restore = <LIMIT>]
Set bandwidth / io limits various operations.

However the action I am performing is create. He creates from a template. Does this fall into the default?
Another doubt is: this limit applies to the operation or applies to the entire time of the container (example: the processes inside the container are also limited to this parameter).


I may also be confused as to what to fill out. He speaks in KiB / s. Today I looked at the container creation log he gave me the average. Total bytes read: 3928913920 (3.7GiB, 7.8MiB / s).
I consider a low average, a ssd should achieve 512Mib / s theoretical. I may be mistaken, but next to that I would have, RAID1, writing competition during the process, besides the CPU time to extract the tar.gz.
I could put a value like
bwlimit: default = 8192
to have a maximum of 8MiB / s?

Sorry my english and thanks for the reply

 

[oguz]

hi,

However the action I am performing is create. He creates from a template. Does this fall into the default?

yes it does.

Another doubt is: this limit applies to the operation or applies to the entire time of the container (example: the processes inside the container are also limited to this parameter).

limits are applied on the operations like create/restore/etc.

bwlimit: default=X should work, where X is a number in KiB/s unit

bwlimit: default = 8192
to have a maximum of 8MiB / s?

yes