Re: [pbs-devel] [PATCH proxmox-backup v2 0/7] improve catalog handling

[Dietmar Maurer <dietmar@proxmox.com>]

> On 07/26/2021 10:37 AM Dominik Csapak <d.csapak@proxmox.com> wrote:
> 
>  
> On 7/26/21 10:26 AM, Dietmar Maurer wrote:
> > 
> >> On 07/22/2021 3:40 PM Dominik Csapak <d.csapak@proxmox.com> wrote:
> >>   
> >> this series combines my previous catalog related patch-series[0][1][2]
> >>
> >> changes the catalog interface to be more concise, optimizes catalog
> >> commit calls during restore, and implements a fast catalog for the
> >> gui which only contains the snapshot lists
> >>
> >> changes from v1:
> >> * only write snapshot list in new 'finish' method of the catalog
> >> * add 'finish' also to pool writer
> >> * replace pending offset counter with reducing the chunk_archive
> >>    interface of the catalog
> > 
> > Now, during tape backup, users do not see any progress on the GUI. This
> > can be particularly confusing on long running tape backups.
> > 
> > A simpler approach would be to only generate cache files for "finished" tapes (content
> > will never change), while using the original catalog for tapes still writable. This should
> > be much easier to implement?
> > 
> 
> yes it would be simpler, but this does not completely solve the issue of
> slow reads on large slow catalogs? (the last tape of the media-set can
> still be so big that the reads take too long?)

I thought the performance problem is on media-sets with many tapes. 
A single catalog should not cause a large delay?