Refresh library

[MrX]

Hi
Is there a way to refresh content of my library without restarting Calibre? My DB folder is on network share and I use it with my wife so if one of us adds something it would be great if second instance of Calibre could update itself with this new data. Best way scenario would be to make this happen automaticly but it would be enough if we could hit some button to refresh contents.

[itimpi]

Originally Posted by MrX

Hi
Is there a way to refresh content of my library without restarting Calibre? My DB folder is on network share and I use it with my wife so if one of us adds something it would be great if second instance of Calibre could update itself with this new data. Best way scenario would be to make this happen automaticly but it would be enough if we could hit some button to refresh contents.

At the moment Calibre is single user and working from network drives is not officially supported. Trying to make changes on two different machines simultaneously will not work as while Calibre is running a lot of information in RAM, so the two instances would stamp on each other's changes.

I believe that Kovid is planning to solve this issue for Calibre v3.

[MrX]

Oh, ok. Thanks.

[theducks]

Originally Posted by MrX

Oh, ok. Thanks.

Not supported, means things can happen that are NOT good. Do at your own peril (and don't whine when it hits )

Calibre use both the DB and file system , as the Library.
Those 2 pieces MUST match. Unfortunately, not all Network share schemes are transactionaly robust (in timing)

NAS are great for backups of your Library, but not (usually) for the active Library

[MrX]

I don't have a NAS per se. I have a custom server with Samba server and the NAS part is one of the things I'm using it for. But thanks for the warning. At the moment everything seems to work fine. I'll set rsnapshot to make backup to be sure.

[eschwartz]

Uhm, I assure you if everything is working fine you have no need for a refresh button. Clearly you are not running multiple simultaneous instances.

calibre holds an in-memory copy of the database, and when it is changed, the change is also written to the database file.
Running two copies of calibre simultaneously against the same library database, means that the two copies are writing different transactions against the same database, without knowing anything about the other's state.
THIS WILL INSTANTLY CORRUPT IT! NO IFS ANDS OR BUTS! DO NOT DO IT! REALLY! I MEAN IT!

It's not even a NAS issue -- you can get the same problem if you run calibre twice on the same computer, though calibre enforces a one-instance-at-a-time rule and you will have to get around it by using multiple user logins or cheating with a 1.x version which uses a different locking mechanism or straight-up hacking the code to remove the restriction...
Nevertheless, it is certainly true that a NAS can lead to multiple-simultaneous-instance violations.

Using a NAS* brings with it a raft of other kinda-somewhat-related problems, and I strongly encourage you not to do so. But unlike multiple-simultaneous-instance violation, they aren't automatically fatal. Some people get away with it due to unreliable, non-duplicable magic... at least until their house of cards collapses and releases the magic smoke. (Mixed metaphors? )

In an upcoming calibre v3 release, the Content Server will be expanded with read/write access and calibre will operate on a server/client architecture. At that time, what you want will be possible (and safe).


* -- It doesn't really matter what the implementation or brand is.

[MrX]

Oh god...Now I'm terrified of even launching Calibre because there may be lurking something in the shadows and waiting to corrupt my soul. :P

Ok. I'll keep that in mind. Fortunately my wife will use both Calibre and Kobo most of the time so the chances of corruption are quite small.

[theducks]

Originally Posted by MrX

Oh god...Now I'm terrified of even launching Calibre because there may be lurking something in the shadows and waiting to corrupt my soul. :P

Ok. I'll keep that in mind. Fortunately my wife will use both Calibre and Kobo most of the time so the chances of corruption are quite small.

Readest thou the Official FAQ least the smite thee
or you insert yourself into the

The stickies at the top of these forum groups might help prevent

[BetterRed]

@MrX - FYI - the Official FAQ on the matter does not lurk in a Mobileread Sticky, it is squirreled away in the manual ==>> I am getting errors with my calibre library on a networked drive/NAS?

BR

[MrX]

I didn't noticed that because I don't have any errors...at the moment at least.
Thanks for the warnings but I'll stick to the SAMBA with daily backups because I find my RAID and backups to be more reliable than HDD in wife's laptop.
And yes, I know I'm doing this at my own risk.

[eschwartz]

Well, as long as you are aware it is risky.

As I said, some people seem to have hit on the right magic combination that makes it Just Work... but no one seems to be sure what that magic is. So you are just lucky I guess.

And you might even stay lucky -- assuming you don't actually try to modify the database with two different instances of calibre at the same time.

[MrX]

I don't how Calibre works so it's hard to guess...all I can do is list what my server looks like: Arch Linux 64bit, RAID1 with ext4 file system, Samba 4.4.3 with config:

create mask = 0664
directory mask = 0775
force create mode = 0664
force directory mode = 0775
map to guest = Bad User
force user = ***
[share]
path = ***
public = yes
available = yes
browsable = yes
writable = yes

*** - yes, those asterisks replaces something that was there :P