Problem with handling large mailboxes (missing pagination / batching)

[RodzynDev]

Hi, first of all, thanks for this project, it’s really useful :D

I’ve encountered a problem when using the tool with very large mailboxes (in my case ~50k+ emails on an IMAP server, specifically Onet.pl).
It seems that the current implementation does not handle pagination or batching when fetching and processing messages.

As a result:

• the script becomes extremely slow or appears to hang,
• memory usage increases significantly,
• in some cases the operation never completes.

From what I can tell, all messages are being fetched and processed in a single run instead of being handled in smaller chunks.
This would significantly improve performance and reliability for large mailboxes.

Thanks you!

[n3wjack]

Hi. Great to hear this app is actually getting some use.

What option are you using exactly? The option to keep a number of emails with the --keep N parameter?
This only reads the messages to delete, but if there are a lot of those, I guess this will indeed be a problem as those are all processed in one go.

[RodzynDev]

Hi, thanks for the quick reply 🙂

Yes, exactly, I’m using the count mode with --keep 100.

In my case the mailbox is quite large (~200k+ messages), so even though only a small number is kept, the number of messages to delete is still very high. It looks like all messages to delete are being fetched and processed in a single batch, which causes the script to hang or become very slow.

So the issue seems to be not just how many messages are kept, but that the deletion set itself is processed all at once instead of in smaller chunks.

I think introducing batching/pagination (e.g. processing UIDs in chunks) would solve this problem for large mailboxes.

And i'm waiting above 30 minutes and still nothing changed, but when I use --keep 200000 then after 10-15 minutes it's begin deleting other messages :D