Re: performance recommendations

[Leonidas Spyropoulos <artafinde@gmail.com>]

Hi Laszlo,

On 16/02/21, Pal, Laszlo wrote:
> Hi,
> 
> Thank you. So, I've installed a new centos7 with the same
> configuration, old kernel and using btrfs. Then, upgraded the kernel
> to 5.11 and all went well, so I thought let's do it on the prod server
> 
Since this is a VM can you clone the disk / partition and attach it to
another VM which running a newer kernel and btrfs progs?

This way you can try debugging it without affecting prod server.

> Unfortunately when I boot on 5.11 sysroot mount times out and I have
> something like this in log
> 
> btrfs open ctree failed
So before that `dmesg` doesn't have any relevant logs?
> 
> Any quick fix for this? I'm able to mount btrfs volume using a rescuCD
> but I have the same issues, like rm a big file takes 10 minutes....

If you manage to mount the disk in a newer kernel and btrfs progs try
creating a new file system to take advantage of the new feature (on
creation) - then migrate the data and follow the recommendations
mentioned already.

Cheers,

-- 
Leonidas Spyropoulos

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